Background Pluorous chemistry is emerging as a powerful adjunct to traditional solution and solid phase methods of parallel and combinatorial synthesis. Fluorous techniques are highly applicable to new drug discovery programs that are being actively pursued worldwide. Further development of this important field presents new challenges to chemists and those interested in solution phase pharmaceutical development.

Introduction to Fluorous Chemnistry Fluorous chemistry is a young science. Whilst there are sporadic reports of chemistry in fluorous solvents in older literature, the systematic study of fluorous chemistry began in 1994, 2 and has spanned fluorous biphasic catalysis2a¢ and conventional organic synthesis 2 h shown promise as an adjunct to solid phase and template methods of combinatorial synthesis, 3 and has provided new separation techniques. 4 The following is a brief outline of the concept and of its current status.

Several highly fluorinated solvents are commercially available and they readily solubilise fluorinated compounds but not purely organic or polar inorganic compounds.

The fluorous solvents are therefore immiscible in many conventional organic solvents and water, and indeed a mixture of the three separates into three phases. Organic materials are partitioned between the three phases depending upon their polarity and degree offtuonnation. This permits organic substrates to be treated in organic solvents with fluorinated reagents and then to have excess reagent or reagent byproducts removed by washing with a fluorinated solvent. Conversely, if the reagent introduces fluorine into the organic substrate, then substrates can be transported into the fluorinated solvent leaving unchanged material in the purely organic solvent The physical operation of solvent extraction is very easy to perform, is amenable to large scale synthesis, and is technically non-demanding.

Many of the requirements for useful separations using the technique have been delineated, 3, 4 and high yields and improved separation efficiencies have been achieved by using various fluorous-phase strategies in which very different chemistry is involved. Synthetic strategies have included the use of highly fluorinated phosphorus

ligands, 5 triaJkyltin and tiialkylsilicon reagents, 7 meditation of reactants through introduction of highly fluorinated trialkylsilicon appendages, 8 and derivatisation of products with highly fluorxnated trialkylsilicon groups to achieve high yields and excellent separation characteristics. 4 These examples convincingly demonstrate the power of doing chemistry in the fluorous phase.

It should be noted that a key element in these separation strategies is that expensive perSuorinated solvents need not be used during reactions. Instead, an inexpensive hybrid solvent, such as supercritical GO9 or trifluoromethylbenzene (benzotrifluoride, BTF), 10 can be used for ffuorous and organic reactants. Reactions can be performed in BTF, or in BTF-organic solvent combinations, and separations effected at a later stage by partitioning the products between an organic solvent, typically dichloromethane (and H20 if necessary), and a fluorous solvent, e. g. FC-7211 (an expensive but recyclable, low boiling fluorinated solvent). Alternatively, reactions in supercritical C02 can be diluted with PC-72, the COz allowed to evaporate, and non-fluorous products precipitated from the fluorous solution, A more recent advance has been the discovery that less Yluorousv substances, that need not be fully partitioned into a fluorous solvent nor be completely insoluble, can be retained on fluorous reverse phase silica gel RPS) in water or polar to moderately polar organic solvents. 6c,12 This development permits another mode of separation, called solid phase extraction (SPE) to be used. The SPE process is akin to chromatography but is performed more like filtration. It has become valuable for cleanup of products in conventional combinatorial synthesis. In its fluorous modification, mixtures are filtered through a bed of the fiuorous gel to remove non- fluorous material. The fluorous component is then recovered by washing the gel with a fluorophilic solvent, such as BTF or ether. this goes beyond existing applications in which SPE is used to remove unwanted byproducts. It also has advantages over purely solid phase techniques, which rely heavily upon filtration, because the fluorous tag does not need to be removed to resolubilise the product.

Despite the very significant progress in modern fluorous chemistry, advances have been made with relatively few reagent types. Mention has already been made of fluorous phosphines as ligands for catalysts, and of trialkyltin and trialkylsilicon compounds for stoichiometric and sub-stoichiometric reagent and scavenging (repêrcher13) use. However, beyond this, few useful fluorous molecular types have been reported, and a call has been made3 for the design of new fluorous reagents that might allow the field of fluorous chemistry to develop to its full potential.

The acetal, ketal, thioacetal and thioketal classes of compounds have found widespread use in organic synthesis, both as useful intermediates and as protected forms of otherwise reactive functional groups. For example, acetals (derived from aldehydes) and ketals (derived from ketones) are commonly used as protecting groups for diols (typically acetonides) and ketones or aldehydes (dioxolanes, dioxanes or analogous acyclic compounds), 14, 15 and there has been much interest in their asymmetric cleavage to generate useful intermediates. 16 Similarly, dithiolanes and dithianes arc conunon protecting groups for ketones and aldehydes. 14,15However, cabanions obtained from 1, 3-difhianc or aldehyde-derived dithianes will also react with electrophiles to give more complex intermediates that can be cleaved to their carbonyl equivalents through hydrolysis or oxidation or to methylene derivatives under reducing conditions 17 A search of the chemical literature has indicated that highly fluorinated (containing more than 4 fully fluorinated sp3 carbons) acetals and ketals have not been reported. Whatsmore, very few molecules that could be used to prepare acetals or ketals by any of the standard methods of acetal and ketal formation have been described and none has been used in this way. Those polyfluorinated reactants that have been described have all been 2-polyfluoroalkylated 1,3-propanediols18-21 Disclosure of Invention The present invention relates (a) to the synthesis of highly fluorinated acetals and ketals and their analogues through (i) reaction ofpolyfluorinated alkanediols and polyfluorinated alkanedithiols and polyfluorinated 1,2-dithiacyloalkanes with carbonyl compounds, especially aldehydes and ketones, and their synthetic equivalents, and (ii) reaction of alkanediols and alkanedithiols with polyfluorinated carbonyl compounds, especially highly fluorinated aldehydes and ketones, (b) the highly fluorinated diol dithiol and 1, 2-dithiacycloalkane reactants in these syntheses, and (c) the resulting highly fluorinated acetals and ketals that are the products of these syntheses, some of which we believe to be novel in themselves.

In a first aspect, the present invention provides method for producing a compound of formula III as shown in reaction Scheme 1 :

Scheme 1 wherein each X is independently selected from O or S; n = 0-2 ; R to ta which may be the same or different, are independently selected from the group consisting of H, optionally substituted straight or branchede alkyl, CF3, optionally substituted aryl optionally substituted aralkyl, optionally substituted aralkylene, optionally substituted straight or branched alkene, optionally substituted, bridged or non-bridged 3-to 8-membered saturated or unsaturated carbocylic or heterocyclic ring and- (CH2) mZR11, in which m = 0-3, Z is 0, S or is absent, or 7 and h together form a substituted or unsubstituted 3-to 8-membered ring R11 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, provided that at least one substituent R'to R8 is the group- (CH2)mZR11; R.''is selected from a single covalent bond between X groups (when X = S), H, SiR103 or C (O) R10, wherein Rlo is optionally substituted alkyl ; and Y is O or (OR10)3.

The present invention also extends to compounds produced by the method of the first aspect of the invention.

The method of the invention may be carried out in the presence of an acid catalyst. Example of suitable catalysts include, but are not limited to H2SO4, CH3SO3H, CF3SO3H, CH3C6H4SO3H, pyridinium p-toluenesulfonate, Me3SiCl, Me3SiO3SCF3, SnCl4, TiCl3, HgCl2, or various lanthanide alkylsulfoante salts, in a non-hydroxylic solvent such as toluene, cyclohexane, or BTF, or in the absence of solvent at elevated temperature with continuous removal of volatailes.

In a second aspect, the invention provides compound of formula I : I wherein each X is independently selected from 0 or S;

n-0-2 ; R1 to R6, which may be the same or different, are independently selected from the group H, optionally substituted straight or branched alkyl, CF3 or a gorup -(CH2)mZR11 in which m = 0-3, Z is O, S or is absent, and t1 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, provided that at least one of R1 to R6 is the group -(CH2)mZR11; and R9 is selected from a single covalent bond between X groups (when X is S), H, SiR103 or C(O)R10 wherein R10 is substituted or unsubstituted alkyl, provided that when each X is 0, n = 1, one or both of R3 and R4 are- (CEt m which m = 0-3 and R11 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, and at least one of R1, R2, R5, R6 or R9 is other that H.

It will be recognized that in some cases compounds of formula I can exist in isomeric forms. This aspect of the invention includes all such possible isomeric forms of the compounds, including diastereomers, enantiomeric forms and mixtures of the isomers.

Compounds of formula I may be produced by techniques known to those skilled in the art. For example, compounds of formula I (X = 0 ; n = 1 or 2) can be prepared through, for example, the addition of organometallic reagents, especially Grignard reagents, in excess on substituted malonate or succinate (including tartrate) esters and through the reduction of substituted malonate and suceinate (including tartrate) esters with hydride reducing agents, especially lithium aluminium hydride. Compounds of formula I (X = O; n = 0) can be prepared through symmetrical or cross reductive coupling of aldehydes and ketones R1R2C=O and R5R6C=O using reagents such as zero valent titanium Or magnesium. They can also be synthesised by methods such as from alpha-hydroxy carboxylic acids and esters, for example, RlR2C (l) 02Et through the addition of excess organometallic reagents, especially ignard reagents, and hydride reducing agents such as lithium aluminium hydride.

Compounds of formula I (X = O; R9 = SiR103 ; n = 0-2) can be prepared from the corresponding alcohols by reaction with trialkylsilylating agents including silyl halides and silyl sulfonates, Compounds of formula I (X = S; n = 0-2) can be prepared from the corresponding alcohols by way of their sulfonate esters or from the corresponding halides (formula 1 ; Cl, Br or I) by treatment with sulfur reagents such as NaSH, R12SNa (in which R12 is alkyl or aryl), HSCH2COaIH or NaSC(O)CH3.

These methods of synthesis are representative and should not be implied or construed a. s being limiting.

In a third aspect, the present invention provides a compound of formula III :

wherein each X is selected independently from 0, S or C* ; n = 0-2 ; R to R8, which may be the same or different, are independently selected from the group consisting of , optionally substituted branched or straight chained alkyl optionally interrupted by one or more heteroatom (s), optionally substituted straight or branched alkene optionally interrupted by heteroatoms, CFa, optionally substituted aryl, optionally substituted aralkyl, optionally substituted arallcylene,, optionally substituted 3-to 8-membered saturated or unsaturated carbocyclic ring, optionally substituted 3-to 8-membered saturated or unsaturated heterocyclic ring, optionally substituted 3-to 8-membered, heteroaromatic ring and- (CH2) mZR", in which m = 0-3, Z is 0, S or is absent, or when n is 1 or 2, at least one of the pairs Rl and R2, R3 and Ruz R5 and R or R7 and R8 optionally from a substituted or unsubstituted 3-to 7-membered ring optionally containing one or more heteroatom (s) or an oxo (=O) group or, when n=0, at least one of the pairs R1 and R2, R2 and R or R and RS optionally form a substituted or unsubstituted 3-to 7-membered ring optionally containing one or more heteroatom (s) or an oxo (=0) group ; and R11 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, provided that at least one substituent Rto f is the group- (CH2)mZR11.

It will again be recognized that in some cases compounds of formula III can exist in isomeric fbrms. This aspect of the invention includes all such possible isomeric forms of the compounds, including diastereomers, enantiomeric forms and mixtures of the isomers.

In a fourth aspect, the present invention provides the use of a compound in accordance with the invention as a solvent.

In a fifth aspect, the present invention provides a composition of matter including a compound in accordance with the present invention.

In another aspect, the invention provides a compound of formula I wherein the R1R2(R9X) C group taken together and the R1R2 (R9X) C group taken together are individually or separately a nitrile (-CN), an ester (-CO2R12), a thionoester (-C(S)OR12), a thiolester (-C(O)SR12), an amide (-CONR12R13) or a thioamide (- CSNR12R13) and n = 1-2; 3 to R, which may be the same or different are independently selected from the group H, CH3, CF3 or a group- (CH2)mZR11 in which m = 0-3, Z = 0, S or is absent, and R11 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, provided that at least one of R3 or R4 is the group -(CH2)mZR11.

It will be recognized that in some cases compounds of formula I can exist in isomeric forms. This aspect of the invention includes all such possible isomeric forms of the compounds, including diastereomers,. enantiomeric forms and mixtures of the isomers.

In another aspect, the invention provides a compound of formula I wherein the R1R2(R9X)C gorup taken together is a nitrile (-CN), an ester (- CO2R12), a thionoester (-C(S)OR12), a thiolester (-C(O)SR12), an amide (-CONR12R13) or a thioamide (-CSNR12R13) and taken individually, X = O or S ; n-0-2 ; Ri to R6, which may be the same or different, are independently selected from the group H, CH3, CF3 or a group- (CH2)mZR11 in which m = 0-3, Z = O, S or is absent,

and R"is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, provided that at least one of R1 to R6 is the group- (CH2)mZR11; and R. ! is selected from a single covalent bond between X groups (when X = S), H, SiR103 or C(O)R10 wherein R10 is alkyl, provided that when X = 0, n = 1, one or both of R and R are -(CH2)mR11 in which m = 0-3 and R11 is a fully fluorinatede straight or branched alkyl chain of 4 to 12 carbons in length, at least one of R1, R2, R5, R6 or R9 is other that H.

It will be recognized that in some cases compounds of formula I can exist in isomeric forms. This aspect of the invention includes all such possible isomeric forms of the compounds, including diastereomers, enantiomeric fonns and mixtures of the isomers.

In yet another aspect, the invention provides a compound of formula I wherein the R1R2(R9X)C group taken together is a branched or straight chain alkyl, aryl, alkaryl polyether or polyamine group that is hydrophobic, hydrophilic or fluorophilic ; and taken individually, X = 0 or S ; n = 0-2 ; 1t3 to R6, which may be the same or differnet, are independently selected from the group H, CH3, CF3 or a group- (CH2) mZR11 in which m = 0-3,Z = O, S or is absent, and R11 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length, provided that at least one of R1 to R6 is the group -(CH2)mZR11; and R9 is selected from a single covalent bond between X groups (when X = S), H, SiR103 or C (O) R10 wherein R10 is alkyl, provided that when X = 0, n = 1, one or both of ruz and R4 are- dCH2) in which m = 0-3 and R11 is a fully fluorinated straight or branched alkyl chain of 4 to 12 carbons in length.

It will be recognized that in some cases compounds of formula I can exist in isomeric forms. This aspect of the invention includes all such possible isomeric forms of the compounds, including diastereomers, enantiomeric forms and mixtures of the isomers.

In another aspect, the present invention provides a compound of formula III

wherein X = 4 or S; n = 0-2; R1-R6, which may be the same or different, are individually selected from the group consisting of H, CH3, CF3 or a group- (CH2)mZR11 in which m = 0-3, Z = O, S or is absent, and A11 is a fully fluorinated straight or branched alky ! chain of 4 to 12 carbons in length, provided that at least one of the substituents R1-R6 is the group- (CH2)mZR11; and The R7R8C gorup when taken together is a carbonyl (C=O), thiocarbonyl (C=S), iminyl (C=NR11), borane (BR15), or borate (BOR15), in which R"is H or CH3, or a branched or straight chain alkyl, aryl, aralkyl, polyether or polyamine group of 2-12 atoms in length that is hydrophobic, hydrophilic or fluorophilic It will again be recognized that in some cases compounds of formula m can exist in isomeric forms. This aspect of the invention includes al ! such possible isomeric forms of the compounds, including diastereomers, enantiomeric forms and mixtures of the isomers.

In a yet another aspect, the present invention provides a compound of formula III III wherein one X = 0 or S ; the second X = CH2, CR16R17, or a carbonyl group ; n=0-2 ; R1-R8, R17, R18 which may be the same or different, are individually selected from the group consisting of H, CH3, CF3 or a group- (CH2)mZR11 in which m = 0-3, Z = O, S or is absent, and R11 is a fully fluorinated straight or branched alkyl chain of 4 to

12 carbons in length, provided that at least one of the substituents Rt is the group- (CH2)mZR11.

It will again be recognized that in some cases compounds of formula M can exist in isomeric forms. This aspect of the invention includes all such possible isomeric forms of the compounds, including diastereomers, enantiomeric forms and mixtures of the isomers.

The present invention also provides a method for producing a chemical product, the method comprising the steps : (a) performing the method of any one of claims 1 to 17 to produce a tagged acetal or ketal of formula III ; (b) chemically transforming the tagged acetal or ketal of step (a) into a modified tagged acetal or ketal of formula If ; (c) chemically transforming the modified tagged acetal or ketal of step (b) to form a product.

Step (b) may repeated 2 or more times.

The term"optionally substituted"as used herein includes a group that may or may not be further substituted'with one or more groups selected from alkyl, optionally bridged cycloalkyl, alkenyl, alkynyl, halo, haloalkyl, haloalkynyl,- (CH2) RIl (where n, Z and Roi are defined above), oxo (=0), hydroxy, COOK alkoxy, alkenyloxy, aryloxy, haloalkoxy, haloalkenloxy, nitro, cyano, amino, nitroalkyl, nitroalkenyl, nitroalkynyl, nitroheterocyclyl alkylamino, dialkylamino, alkenylamine, alkynylamino, hydrazone, CHO, acyl, alkenacyl, alkynylacyl, acylamino, diacylamino, acyloxy, alkylsulphonyloxy, heterocyclyl, heterocycloxy, heterocyclamino, haloheterocyclyl, <BR> <BR> <BR> alkylsulphenyl, carboalkoxy, alkylthio, acylthio, phosphorous-containing groups such as phosphono and phosphinyl, or a residue of a compound of formula III or a residue of compound of formula IH and an associated linking group.

The term "alkyl" includes straight chain or branched C1-6 alkyl groups. Non- limiting examples include methyl, ethyl, propyl, isopropyl and the like.

The term"alkoxy"includes straight chain or branched alkoxy. Non-limiting examples include methoxy, ethoxy, n-propoxy, isopropoxy and the different butoxy isomers.

The term"alkenyl"includes groups formed from straight chain, branched or mono-or poly-cyclic alkenes including ethylenically mono-or poly-unsaturated alkyl or cycloalkyl groups Non-limiting examples of alkenyl include vinyl, allyl, 1- methylvinyl, butenyl iso-butenyl, 3-methyl-2-butenyl, 1-pentenyl, cyclopentenyl, 1-

methyl-cyclopentenyl, 1-hexenyl, 3-hexenyl, cyclohexenyl, 1-heptenyl, 3-heptenyl, 1- octenyl, cyclooctenyl, 1-nonenyl, 2-nonenyl, 3-nonenyl, 1-decenyl, 3-decenyl, 1, 3- butadienyl, 1-4, pentadienyl, 1, 3-cyclopentadienyl, 1, 3-hexadienyl, 1, 4-hexadienyl, 1,3- cyclohexadienyl, 1, 4-cyclohexadienyl, 1,3-cycloheptadienyl, 1,3,5-cycloheptatrienyl, 1,3, 5, 7-cyclooctatetraenyl.

The term"aryl"as used herein includes an aromatic substituent containing a single aromatic ring or multiple aromatic rings that are fused together, linked covalently, or linked to a common group such as a methylene or ethylene moiety. The common linking group may also be a carbonyl as in benzophenone, an oxygen atom as in diphenylether, an alkylether or a nitrogen atom as in diphenylamine.

The term "aralkyl" refers to an alkyl group with an aryl substituent, and the term "aralkylene"refers to an alkylen group with an aryl substituent ; the term"alkaryl" refers to an aryl group that has an alkyl substituent, and the term "alkarylene" refers to an arylene group with an alkyl substituent.

The term "acyl" used either alone or in compound words such as"acyloxy", "acylthio", "acylamino" or diacylamino" denotes carbamoyl, aliphatic acyl group and acyl group containing a heterocyclio ring which is referred to as heterocyclic acyl, preferably Cl-10 acyl. Examples of acyl include carbamoyl ; straight chain or branched alkanol, such as formyl, acetyl, propanoyl, butanoyl, 2-methylpropanoyl, pentanoyl, 2,2-dimethylpropanoyl, hexanoyl, heptanoyl, octanoyl, nonanoyl, decanoyl; alkoxycarbonyl such as methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl, t- pentyloxycarbonyl or heptyloxycarbonyl ; cycloalkylcarbonyl such as cyclopropylcarbonyl cyclobutyloarbonyl, cyclopentylcarbonyl or cyclohexylcarbonyl ; alkylsulfonyl, such as methylsulfonyl or ethylsulfonyl ; alkoxysulfonyl, such as methoxysulfonyl or ethoxysulfonyl ; heterocyclylcarbonyl ; heterocyclylalkanoyl, such as pyrrolidinylacetyl, pyrrolidinylpropanoyl, pyrrolidinylbutanoyl, pyrrolidinylpentanoyl, pyrrolidinylhexanoyl or thiazolidinylacetyl ; heterocyclylalkenoyl, such as heterocyclylpropenoyl, heterocydylbutenoyl, heterocyclylpentenoyl or heterocyclylhexenoyl ; or heterocyclylglyoxyloyl, such as, thiazolidinylglyoxyloyl or pyrrolidinylglyoxyloyl.

The term"alkoxy"as used alone or in combination herein refers to a straight or branched chain alkyl group covalently bonded to the parent molecule through an-0- linkage containing from one to ten carbon atoms and the terms"C 1-6 alkoxy"and "lower alkoxy"refer to such groups containing from one to six carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, tbutoxy and the like.

The term"heteroaromatic"group as used herein refers to a stable, aromatic monocyclic or polycyclic ring system containing carbon atoms and other atoms selected from nitrogen, sulfur and/or oxygen. For example, the heteroaromatic group may be a 5 or 6-membered monocyclic ring (optionally benzofused) or an 8-11 membered bicyclic ring which consists of carbon atoms and contains one, two, or three heteroatoms selected from nitrogen, oxygen and/or sulfur. The term "optionally substituted"as it refers to"heteroaromatic"herein indicates that the heteroaromatic group may be substituted at one or more substitutable ring positions by one or more groups independently selected form alkyl (eg lower alkyl), alkoxy (eg lower alkoxy), nitro, monoalkylamino (eg a lower alkylamino), dialkylamino (eg a di [lower] alkylamino, cyano, halo, haloalkyl (eg trifluoromethyl), alkanol, aminocarbonyl, monoalkylaminocarbonyl, dialkylaminocarbonyl, alkyl amido (preferably lower alkyl amido), alkoxyalkyl (eg a lower alkoxy [lower] alkyl), alkoxycarbonyl (eg a lower alkoxycarbonyl), alkylcabonyloxy (eg a lower alkylcarbonyloxy) and aryl (eg phenyl), said aryl being optionally substituted by halo, lower allyl and lower alkoxy groups. Examples of such beteroaromatic groups are isoxazolyl, imidazolyl, thiazolyl, isothiazolyl, pyridyl, furyl, pyrimidinyl, pyrazolyl, pyridazinyl, furazanyl and thienyl. The heteroaryl group may be attached to the parent structure through a carbon atom or through any heteroatom of the heteroaryl that results in a stable structure.

The terms"halo"and"halogen"as used herein to identify substituent moieties, represent fluorine, chlorine, bromine or iodine, preferably chlorine or fluorine.

The term"cycloalkylene", includes divalent cyclic Cs. io alkyi groups. Non- limiting examples include cyclopropyl, cyclobutyl, cyclopentyl and cycloheptyl. The term includes fused rings and bridged rings.

The term"heterocyclyl"as used alone or in compound names such as "alk3rleneheterocyclyl"denotes 3-to 8-membered heterocyclic rings. Examples of 5 or 6 membered heterocyclic rings include pyrrolidine, imidazolidine, pyrazolidine, thiazolidine, isothiazolidine, oxazolidine, piperidine and piperazin The term"tag"refers to a substituent comprising a polyfluor alkyl group.

Methods for carrying out the invention The invention is further described in and illustrated by the following examples..

These examples are not to be construed as limiting the invention in any way.

1, Examples of methods for the preparation of polyfluorinated diol reagents 1 2 3 1. 4 5 6 2- (3, 3,4, 4, 5, 5, 6,6,7,7,8,8,8-Tridecafluorooctyl)-1,3-propanediol 1 A solution of diethyl 2-(3, 3, 4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-propanedioate (1. 956 g, 3.9 mmol) in dry Et, 20 (20 rnL) was added to a suspension of LiAlH4 (0.340 g mmol) in dry Et20 (20 mL) at such a rate as to maintain reflux. The mixture was stirred at ambient temperature for 20 h then quenched by careful addition of 10% aq. solution (20 mL). The mixture was filtered under suction through a pad of filter aid. The pad was washed with fresh Etc0 (2 x 20mL), the combined filtrate and washings separated and the aqueous layer extracted with more Et20 (2 x 15mL) The organic layers were combined and evaporated under vacuum to afford a white solid (1.522 g). Thorough extraction of the solid with light petroleum and recrystallization of the remaining white solid from CH2Cl2 afforded 2-(3, 3,4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8- tridecafluorooctyl)-1, 3-propanediol 1 as white flakes (1. 323 g, 81%) ni. p 72-74°C (Found : C, 31.24; H, 2.88 C11H11F13O2 requires: C, 31. 29 ; H, 2.63%). 1H NMR (300 MHz) : 3 1. 67, m, (H1')2 ; 1. 78, m, H2; 1.99, s, 2-OH; 2.17, br m, (H2')2', 3. 72, dd, J 10. 6, 6.0 Hz, Hal and Ha3; 3.85, dd, J 10, 6, 3.8 S Hb1 and Hb3. 13C NMR (75.6 MHz): # 18, 4, t, J 4.0 Hz, C1'; 28.7, t, J 22.5 Hz, C2'; 41.2, C2 ; 65.0, Cl and C3. Mass spectrum : ? nlz 422 (M, absent), 374 (15%), 169 (5), 119 (12), 105 (18), 77 (18), 69 (31), 57 (70), 55 (100).

2, 2-Bis (3, 3, 4, 4, 5,5,6,6, 7, 7,8,8,8-tridecafluorooctyl)-1,3-propanediol 2 (a) A. solution. of diethyl 2, 2-bis (3, 3,4, 4, 5,5,6,6,7, 7, 8,8,8- tndecafluorooctyl) propanedioate (0. 697 g, 0. 82 mmol) in dry Et2O (6 mL) was added dropwise to a suspension of LiAlH4 (0.080 g, 2.11 mmol) in dry Et2O (6 mL). This mixture was stirred at ambient temperature for 24 h, then quenched by careful addition

of 10% aq. KOH solution (5 mL). The mixture was filtered under suction through a pad of filter aid. The pad was washed with fresh Et2O (2x20mL). The combined filtrate and washings were separated and the aqueous layer extracted with more EtoO (2x15 mL).

The organic phases were combined and evaporated under vacuum to afford white solid (0.605 g). The white solid was recrystallized from CHCl3 to afford 2, 2- bis (3, 3,4,4,5,5, 6,6, 7, 7,8,8,8-tridecafluorooctyl)-1,3-propanediol 2 as white needles (0. 572 g, 91%) m. p. 73-75°C (lit.18 m p. 77-77, 5°C) (Found : C, 30. 06; H, 1. 97.

C19H14F26O2 requires: C, 29.70; H, 1.84%). 1H NMR (300 MHz): # 1. 66, m, tel') 2 and (H1") 2 ; 1.90, s7 2-OH ; 2. 13, br m, (H2')2 and (H2")2; 3. 61, s, (Hl) 2 and (H3)2. 13C NMR (75. 6 MHz) : ##1#C1' and C1"; 25.1, t, J22.2 Hz, C2' and C2"; 40. 0, C2 ; 66. 8, Cl and C3. Mass spectrum : mlz 768 nez absent), 721 (201/o), 413 (6), 401 (62), 375 (9), 327 (5), 169 (20), 131 (25), 119 (45), 95 (33), 77 (50).

(b) (i) A mixture of3, 3, 4, 4, 5, S, 6, 6,7,7,8,8,8-tridecafluoroctyl iodide (10. 653 g, 22. 47 mmol), ethyl cyanoacetate (J. 232 g, 10. 89 mmol), anhydrous K2CO3 solid (3.323 g, 24. 08 mmol) and dry DMF (15 mL) was stirred together in a flame-dried flask for 20 h under argon. The resulting reaction mixture was poured into water and filtered to remove the red precipitate. The precipitate was dissolved in Et2O (50 mL) and the solution was decolourized by addition of charcoal. The solution was filtered and then evaporated to dryness to give some pale solid that was recrystallized from light petroleum to afford ethyl 2,2-bis(3,3,4,4,5,5,6,6,7, 7, 8,8,8- tridecafluorooctyl)cyanoacetate 71 as white needles (6. 516 g, 74%) m. p. 66-67°C (Found: C, 31.26 ; H, 1. 5S ; N, 1. 84. C21H13F26NO2 requires: C, 31.32; H, 1.63 ; N, 1.74%). vmax 1744, 1320, 1240, 1190, 1141, 1043, 699. 1H NMR (300 MHz): # 1.36, t, J 7. 0 Hz, CO2CH2CH3; 2. 17, m, (H1') 2 and H1")2 ; 2. 31, br m, (H2')2 and (H2")2, 4. 37, q, J 7. 2 HA CO2CH2CH3. 13C NMR (75. 6 MHz) : #13.8, CO2CH2CH3 ; 27. 3, t, J 2Z 5 Hz, C2' and C2"; 28.1, C1' and C1"; 47.5, C2; 63.8, CO2CH2CH3; 116.8, CN; 166. 7, CO2CH2CH3.Mass specturm: m/z 806 (M+1, 2%), 733 (25), 508 (12), 428 (72), 400 (100), 327 (11), 169 (20), 131 (30), 119 (38), 77 (53), 69 (82).

(ii) Conc. H2SO4 (5 mL) was slowly added to a solution of ethyl 2,2- bis (3, 3, 4, 4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)cyanoacetate 71 (5. 370 g, 6. 67 rnmol) in n-BuOH (50 mL), and the mixture heated at reflux for 3 days. The brown solution was cooled, fizz (50 mL) and EtO (50 mL) were added, and the resulting mixture was

separated and the aqueous layer was extracted with more Et20 (2 x 25 mL). The organic phases were combined and evaporated under vacuum to afford brown solid (5. 922 g which was chromatographed on silica gel (40 g). The first fraction, eluted with 4 : 96 EtzO/light petroleum was combined and evaporated to dryness to give largely di-n-butyl 2, 2-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-triedcafluorooctyl)propanedi oate as a yellow oil (1. 872 g). The second fraction from 4:96 Et2O/light petroleum was recrystallized £rom light petroleum to give n-butyl 2,2-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)cyanoacetate 72 as white Hakes (3.039 g 55%) m. p. 66-67°C (Found: C, 33.07; H, 2.18; N, 1.59. C21H13F26NO2 requires: C, 33. 15 ; H, 2. 06; N, 1.68%). #max 1732, 1321, 1240, 1189, 1139, 1044, 699, 658. 1H NMR (300 MHz): # 0. 96, t J 7.3 Hz, CO2CH2CH2CH2CH3; 1. 42, m, J 7. 4 Hz, CO2CH2CH2CH2CH3; 1.70, m, J 7.2 HzCO2CH2CH2CH2CH3; 2.16, m, (Hl')2 and (Hl")2; 2.31, br m, (H2') 2 and (H2") 2 ; 4. 30, t, J 6. 6 Hz, CO2CH2CH2CH2CH3. 13C NMR (75.6 MHz): #13.2, CO2CH2CH2CH2CH3; 18.8, CO2CH2CH2CH2CH3; 27.4, t, J 22.5 Hz, C2' and C2"; ?-S. I, t, J 4.4 Hz, Cl'and Cl 30. 2, C02CH2CH2CH2CH3 ; 47. 6, C2; 67. 6, CO2CH2CH2CH2CH3; 116. 7, CN; 166.8, CO2CH2CH2CH2CH3. Mass spectrum: m/z 833 (M", absent), 733 (15°/0, 508 (7), 414 (3), 400 (58), 386 (3), 327 (5), 169 (5), 130 (8), 119 (10), 84 (17), 77 (26), 69 (36), 57 (100).

(iii) A solution of the first fraction from part (ii), a yellow oil (1. 872 g), in dry Et2O (15 mL) was added dropwise to a suspension of LiAIH4 (0. 235 g, 6. 16 mmol) in dry Et2O (8 mL) This mixture was stirred at ambient temperature for 24 h, then quenched by careful addition of 10% aq. KOH solution (20 mL). The mixture was faltered under suction through a pad of filter aid. The pad was washed with fresh Et2O (3 x 20mL).

The combined filtrate and washings were separated and the aqueous layer extracted with more Et20 (2 x 20 mL). The organic phases were combined and evaporated under vacuum to afford a white gel (1. 656 g). The white gel was then chromatographed on silica gel (20 g). The first fraction, eluted with 20: 80 Et2O/light petroleum was combined and evaporated, and the residue was distilled to give 2, 2- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-triedcafluoroctyl)-l-ethanol 49 as a colouless oil (0.766 g, 16%) 160°C (oven)/1.0 mmHg

49 (Found: C, 29. 41 ; l 1, 71. C18H12F26O requires : C, 29. 29 ; H, 1. 64%). 1H NMR (300 MHz): #1. 41, s, OH; 1.66, m, (H1')2, (H1") 2 and H2 ; 2, br X and (H2")2; 3.64, s, (H1)2. 13C NMR (75.6 MHz) : Q21. 4, Cl'and Cl" ; 28. 4, t, J 22.2 Hz, C2' and C2"; 38.9 C2; 64. 2, Cl. Mass spectrum : m/z 738 (M+, absent), 706 (1), 686 (2), 401 (3), 169 (12), 131 (15), 119 (32), 91 (13), 77 (53), 69 (100), 55 (69). The second fraction from 50 ;50 Et2O/light petroleum was combined, evaporated and recrystallized ftom CHCla to afford 2, 2-bis (3,3, 4,4,5,5,6,6, 7, 7,8,8,8-tridecafluorooctyl)-1,3-propanediol 2 as white needles (0, 774 g, 15%).

Cone. H SO4 (4 5 mL) was slowly added to a solution of ethyl 2, 2- bis (3, 3, 4, 4, 5,5,6,6,7,7,8,8,8-tridecafluorooctyl)cyanoacetate 71 (4.80 g, 5. 96 mmol) in n-BuOH (45 mL), and the solution heated at reflux for 7 d. The brown solution was cooled, lI20 (50 mL) and EtzO (50 mL) were added, the resulting mixture was separated, and the aqueous layer was extracted with more Et2O (2 x 25 mL). The organic phases were combined, dried and evaporated under vacuum to afford the crude dibutyl diester as a brown oil (5.02 g).

(iii) The oil (5. 02 g) was dissolved in dry EtO (30 mL) and added dropwise to a suspension of LiAIH4 (0. 50 g, 13. 16 mmol) in dry Et20 (20 mL). The mixture was stirred at ambient temperature for 24 h, then quenched by careful addition of 10% aq.

KOH solution (20 mL). The mixture was filtered under suction through a pad of filter aid, and the pad washed with fresh Et2O (3 x 20 mL). The combined filtrate and washings were separated and the aqueous layer extracted with more EtO (2 x 20 mL).

The organic phases were combined and evaporated under vacuum to afford a brown oil (4.37 g), which was chromatographed on silica gel (50 g). The first fraction, eluted with 20 ; 80 Et2O : light petroleum, was combined and evaporated, and the residue was distilled to give 2,2-bis(3,3,4,4,5,5,6,6,m 7, 7,8,8,8-tridecafluorooctyl)-1-ethanol 49 as a colourless oil (1.45 g, 34%) The second fraction, from 50 : 50 EtwO : light petroleum, was combined, evaporated and recrystallized from CHOIS to afford 2, 2- bis (3, 3, 4,4,5, 5,6, 6, 7,7,8,8,8-tridecafluorooctyl)-1,3-propanediol 2 as white needles (1. 89 g, 44%).

l, 1-Bis (3,3, 4,4, 5, 5, 6, 6,7,7,8,8,8-tridecafluorooctyl)-2,2-dimethyl-1,3-propanediol 3 (i) 3, 3, 4,4,5,5,6,6,7, 7,8, 8, 8-Tridecafluorooctyl iodide (0.903 g, 1.91 mmol) was added to a suspension of Mg powder (0. 636 g, 26. 20 mmol) in dry Et2O (15 mL) under argon.

The mixture was sonicated for 30 min then more 3, 3, 4, 4, 5, 5, 6, 6,7,7,8,8, 8- tridecafluorooctyl iodide (9. 074 g, 19. 14 mmol), in dry EtsO (20 mL), was added dropwise over 60 min at such a rate that gentle reflux was maintained. Upon complete addition, the mixture was stirred at reflux for a further 90 min then cooled to room temperature and a solution of diethyl dimethylmalonate (1. 671 g, S. 88 mmol) in dry Et2O (4 mL) was added slowly. The mixture was stirred for a iurther 2 d at ambient temperature then quenched carefully by dropwise addition of sat. aq. CI solution.

The aqueous layer was extracted with Et2O (3 x 20 mL) and the original organic layer and the extracts were combined, dried over anhydrous Na2SO4, and evaporated to dryness to give a yellow oil (7.847 g) that was column chromatographed on silica gel.

The forera from light petroleum gave 1, 4-bis (perfluorohexyl) butane as a white solid (1. 093 g, 7%) The major fraction, eluted with 3: 97 EtxOllight petroleum, was evaporated to dryness and the residue wa distilled ot give ethyl 3,3,-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-2,2-dimethyl-3-hydroxypropionate 73 as a colourless oil (5. 970 g, 80%) b. p 120°C (oven)/04. mmHg (Found : C, 32. 89; H, 2.53. C23H20F26O3 requires: C, 32.95; H, 2.40%), #max 3452, 2990, 1743, 1698, 1475,. 1367, 1203, 1059, 847, 811, 735, 708 cm-1. 1H NMR (300 MHz, CDCl3): #1, 27, s, 2-CH3 ; 1. 30, t, J 7.2 Hz, CO2CH2CH3 ; 1. 57-1. 89, br m, (H1') 2 and (H1")2 ; 2. 00-2. 40, br m, 9H2')2 and (H2")2; 4. 20, q, J 7. 2 Hz, C02CH2CH3, 4. 48, s, OH_13C NMR (75.6 MHz): # 13.7,CO2CH2CH3; 20.9, 2xCH3 ; 26. 1, t, J21.8 Hz, C2' and C2"; 26.7, C1' and Cl"; 50.4, C2; 61.6, CO2CH2CH3; 73.7, C3; 178.7, CO2CH2CH3. Mass spectrum; m/z 838 (M+, absent), 703 (15%), 551 (5), 491 (40), 453 (35), 417 (30), 389 (45), 375 (95), 327 (25), 263 (25), 213 (25), 169 (28), 131 (50), 116 (100), 88 (95), 70 (92).

(ii) A solution of ester 73 (1. 611 g, 1. 92 mmol) in dry Et2O (12 mL) was added dropwise to a suspension of LiAlH4 (0. 193 g, 5, 07 imnol) in dry Eut20 (5 mL). This mixture was stirred at ambient temperature for 24 h then quenched by careful addition of 10% aq. KOH solution (5 mL). The phases were separated and the aqueous layer

was extracted with Et2O (2 x 15 mL). The organic phases were combined, evaporated and the residue was distilled to _ afford 1.1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-2,2-dimethyl-1,3-propanediol 3 as a colourless oil (1. 486 g, 97%) b. p. 140°C (oven)/0.3 mmHg (Found: C, 31. 91 ; H, 2.25. C21H18F26O2 requires : C, 31. 67; H, 2. 28%). #max 3370, 2973, 2891, 1475, 1366, 1318, 1209, 1146, 1057, 114 NMR (300 MHz): #0.99, s, 2-CH3 ; 1. 71, dt, J 12. 8, 3. 8 Hz, (HII) 2 ; 1. 98, dt, J 13. 6, 3. 8 <BR> <BR> Hz, (H1") 2; 2.14, s, CH2OH; 2.16, m, (H2')2; 2.33, m, (H2")2; 3.69, d, J 3.8 Hz, H3 ;<BR> <BR> <BR> 3.95, s, (C6F13CH2CH2)2COH, 13C NMR (75.6 MHz); #20.8, 2xCH3; 26.1, Cl' and Cl" ; 26. 4, t, J 11.8 Hz, C2' and C2''; 41. 9, C2 ; 71. 5, C3 ; 75. 3, Cl. Mass spectrum : mlz 796 (M-, absent), 761 (18%)l, 723 (18), 449 (65), 431 (58), 375 (95), 327 (22), 263 (18), 169 (30), 119 (45), 77 (68), 69 (100). l, 1-Bis(3,3,4,4,5,5,6,6.7,7.8,8,8-tridecafluorooctyl)-1,2-etha nediol 5 (i) Reaction of (3, 3, 4, 4,5, 5, 6, 6, 7, 7, 8, 8, 8-tridecafluorooctyl) magnesium iodide with diethyl oxalate A portion of 3, 3,4, 4,5, 5, 6, 6, 7,7, 8, 8, 8-tridecafluorooctyl iodide (0. 933 g, 1. 97 mmol) was added to a suspension of Mg powder (0. 731 g, 4.13 mmol) in dry Et2O (10 mL) under argon. The mixture was sonicated for 30 min then a solution of 3,3, 4, 4, 5, 5,6, 6,7, 7,8, 8, 8-tridecafluorooctyl iodide (8. 726 g, 18. 41 mmol) in dry Et2O (25 nL) was added dropwise over 60 min. Upon complete addition, the mixture was stirred at reflux for a further 90 min then cooled to room temperature and a solution of diethyl oxalate (1. 247 g, 8.53 mmol) in dry Et2O (5 mL) was added slowly. The mixture was stirred for a further 2 d at ambient temperature then quenched carefully by dropwise addition of sat. aq. NH4Cl solution. The aqueous layer was separated and extracted with Et2O (3 x 20 mL). The original organic layer and extracts were combined, dried over anhydrous Na2SO4 and evaporated to dryness to give a yellow oil (6.400 g) that was column chromatographed on silica gel. The faction from light petroleum gave 1, 4-bis(perfluorohexyl)butane as a white solid (1.230 g, 8%). The major fraction, eluted with 5:95 Et2O/light petroleum, was evaporated to dryness and then distilled to give ethyl 2, 2-bis (3, 3, , 4,5,5,6,6,7, 7, 8, 8, 8-tridecafluorooctyl)-2- hydroxyacetate 74 as a colourless oil (2. 119 g, 31%) b. p. 120°C (oven)/0. 4 mmHg . F13 O2Ho C, H I H 6F, 3

(Found : C, 30. 20 ; H, 1. 80. C21H18F26O2 requires : C, 30. 17; H, 1. 77%). 1H NMR (300 MHz,) : #1.32, t, J7.2 Hz, CO2CH2CH3; 1.86, br m, (H2')2; 1. 95-2. 12, br m, (H1')2 and (H1'')2; 2.30, br m, (H2'')2; 3.38, s, OH ; 4. 32, q, J7.2 Hz, CO2CH2CH3. 13C NMR (75. 6 Nfffz) : #13.9, CO2CH2CH3 ; 25. 6, t, J 22. 5 Hz, C2' and C2''; 29.4, C1' and C1''; 63. 0, C2; 74.8, CO2CH2CH3; 174. 9, CO2CH2CH3. Mass spectrum; m/z 796 (M+, absent), 779 (5%), 723 (92), 703 (52), 683 (12), 449 (20), 403 (33), 375 (100), 327 (84), 169 (47), 119 (53), 69 (91). The fraction from 10 : 90 Et2O : light petroleum was distilled to afford ethyl 2-hydroxy-2-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)ac etate 75 as a colourless oil (1. 512 g, 39%) b. p. 120°C (oven)/l. 0 mmHg (Found : C, 32. 04; H, 2, 54. C12H11F13O3 requires: C, 32.02; H, 2.54%). #max 3471, 2988, 1740, 1455, 1367, 1240, 1145, 1121, 1096, 1076, 1021, 707, 1H NMR (300 MHz): #1.32, t, J 7.2 Hz, CO2CH2CH3 ; 1. 92, m, Ha1'; 2.12, m, Hb1'; 2.15-2.35, br m, (H2') z ; 2. 87, d, J 4.9 Hz, OH ; 4. 22, m, H2 ; 4.26, dq, J 10. 9, 7.2 Hz, CO2CHaHbCH3; 4. 31, 1, dq, J 10.9, 7.2 Hz, CO2CHaHbCH3. 13C NMR (75.6 MHz): #14.0, CO2CH2CH3; 25.0, t, J4.0 Hz, C1'; 26. 7, t, J 22.5 Hz, C2'; 62.1, CHOH; 68.9, CO2CH2CH3 ; 174.0, CO2CH2CH3. Mass spectrum : mlz 451 %), 377 (100), 357 (52), 337 (9), 309 (12), 289 (15), 245 (12), 239 (13), 169 (8), 131 (15), 119 (22), 69 (67).

(ii) A solution of ester 75 (1. 212 g 2 mmol) in dry Bt2O (5 mL) was added dropwise to a suspension of LiAlH4 (0.160 g, 4. 22 mmol) in dry Et20 (20 mL). This mixture was stirred at ambient temperature for 20 h, then quenched by careful addition of 10% aq.

KOH solution (10 mL). The phases were separated and the aqueous layer was extracted with Et2O (4 X 15 nnL) The organic phases were combined and evaporated to give a colourless oil (1. 332 g) that solidified when it stood overnight at room temperature. The white solid was recrystallized from CH2Cl2 to give 1,1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,2-ethanediol 5 as white needles (1. 114g, 97%) mp. S4-85°C (Found C, 28. 68; H, 1. 69. C18H12F26O2 requires; C, 28.66 ; H, 1.60%). #max 3344, 1319, 1235, 1208, 1189, 1145, 1122,1070, 699. 1H NMR (300 MHz): #1. 80, m, 2-OH, (Hl') 2 and (H1'') 2; 2.20, br m, 1-OH, (H2')2 and (H2") : ; 3. 55, d, J 4.1 Hz, (H2) 2. 13c NMR (75. 6 MHz): #25.3, t, J 22. 7 Hz, C2'and C2" ; 26. 7, t, J 3.6 Hz, C1' and C1''; 66. 9, C2 ; 71.8, C1. Mass spectrum: m/z 754 (M+, absent), 723 (58%), 703 (22), 467 (8), 407 07 (95), 389 (35), 375 (65), 327 (33), 169 (32), 119 (52), 69 (100).

l, l-Bis (3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,8, 8-tridecafluorooctyl)-1,4-butanediol 6 (i) A portion of 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,8,8-tridecafluorooctyl iodide (0. 592 g, 1.25 mmol) was added to a suspension of Mg powder (0. 375 g, 15. 42 mmol) in dry Et20 (10 mL) under argon. The mixture was sonicated for 30 min then a solution of 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8,8,8-tridecafluorooctyl iodide (4. 561 g, 9. 62 mmol) in dry Et20 (20 mL) was added dropwise over 60 min. Upon complete addition, the mixture was stirred at reflux for a further 90 min then cooled to room temperature and a solution of diethyl succinate (2.010 g, 11.54 mmol) in dry Et7O (4 mL) was added slowly. The mixture was stirred for a further 2 d at ambient temperature then quenched carefully by dropwise addition of sat. aq. NH4Cl solution. The aqueous layer was separated and extracted with Et2O (3 x 20 mL). The original organic layer and extracts were combined, dried over anhydrous Na2SO4 and evaporated to dryness to give a yellow oil (4. 786 g) that was column chromatographed on silica gel. The fraction from light petroleum gave 1, 4-bis (perfluorohexyl) butane as a white solid (0. 629 g, 8%). Diethyl succinate (1.267g, 63%) was recovered from the fraction eluted with 10 : 90 Et2O : light petroleum. The major traction, eluted with 40 : 60 EtO : light petroleum, wa. s evaporated to dryness and distilled to give 4,4-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)butyrolactone 76 as a colourless oil that solidified after standing overnight at ambient temperature (1.760 g, 21%) b. p. 170°C (oven)/0. 6 mmHg m.p. 54- 54. 5°C (Found : C, 30.99; H, 1. 52. C20H12F26O2 requires: C, 30.87 ; H, 1.55%). #max 2722, 1776, 1246, 1203, 1189, 1144, 1071, 1031, 699. 1H NMR (300 MHz): #1.97, m, (Hl') 2 and (H1'')2 ; 2 13, t, l 8. 7 Hz, (H4) 2 ; 2. 16, br m, (H2') 2 and (H2") 2 ; 2. 68, t, I 8. 5 Ha, (H3) 2. 13C NMR (75.6 MHz): #25.5, t, J22.5 Hz, C2' and C2''; 28.2, C3; 28.7, C1' and Cl" ; 30. 5, C4 ; 84.5, C5; 174.8, C2. Mass spectrum: m/z 778 (M+, absent), 703 (7%), 375 (5), 327 (3), 169 (3), 147 (28), 103 (74), 73 (100). NMR. spectroscopic assignments were confirmed by 1H-1H COSY and 1H-13C HMQC experiments.

(ii) A solution of lactone 76 (1.345 g, 1.73 mmol) in dry Et (8 mL) was added dropwise to a suspension of LiAlH4 (0.152 g, 4.00 mmol) in dry Et2O (8 mL). This mixture was stirred at ambient temperature for 20 h, then quenched by careful addition of 10% KOH solution (10 mL). The phases were separated and the aqueous layer was extracted with Et2O (4 x 15 mL). The organic phases were combined and evaporated to give a colourless oil (1.332 g) that solidified when it stood overnight at room

temperature. The white solid was then recrystallized from CH2Clz to give 1,1- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,4-butane diol 6 as white needles (1. 328 g, 93%) m. p. 65-66°C (Found : C, 30. 54 ; H, 2. 06. C20H16F26O2 requires: C, 30. 71; H, 2. 06%). vt 3368, 1319, 1241, 1208, 1145, 1038, 697. 1H NMR (300 MHz): # 1. 65, br s, (H2) 2 and (H3) 2; 1.75, m, (H1')2 and (H1'') 2; 2.17, br m, (142') 2 and (H2") 2 ; 3. 74, s, (H4) 2 13C NMR (75.6 MHz): #25. 4, t, J 22.2 Hz, C2' and C2''; 25. 9, C3; 29. 1, Cl'and Cl" ; 36.0, C2; 62. 7, C4 ; 71. 2, Cl. Mass spectrum : m/z 782 (M+, absent), 723 (22%), 703 (7), 435 (5), 417 (65), 375 (30), 327 (7), 169 (5), 69 (33), 42 (100).

Synthesis of polyfluorinated diol trimethylsilyl ethers 1,1-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-bi s(trimethylsilyloxy)-2,2- dimethylpropane 77 77 Diol 3 (0. 791 g, 0.99 mmol), 1, 1, 1,3,3,3-hexamethyldisilazane (2. 830 g, 17.53 mmol) and iodine (0. 043 g 0. 17 mmol) were refluxed overnight in CH2C12 (30 mL). The solution was cooled and finely ground Na2Sz03 powder (0. 210 g, 1. 33 mmol) was added and the resulting mixture was stirred for another 1 h. The CH2Cl2 solution was filtered and the residue was washed with Et20 (2 x 20 mol). The original filtrate and washings were combined and evaporated. under vacuum to afford a colourtess oil (0.874 g) that was column chromatographed on silica gel. The fraction eluted with 3 : 97 Et20 : light petroleum was distilled to give J. 1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-bis(trimethylsilyloxy)-2,2-dimethylp ropane 77 as a colourless oil (0.435 g, 47%) b. p. 120°C (oven)/0. 4 mmHg (Found: C, 34.47; H, 3. 57.

C27H34F26O2Si2 requires : C, 34. 7; H, 3. 64%). Vmax 2962, 2905, 2885, 1479, 1366, 1318, 1240, 1203, 1145, 1088, 873, 841. 1H NMR (300 MHz) : #0. 08, s, 3-0si (CR,,) 3 ; 0.15, s, 1-OSi (CH3) 3 ; 0. 90, s, 2xCH3 ; 1. 94, br m, (H1')2 and (H1'')2; 2. 13, br m, (H2') 2 and (H2") 2 ; 3. 39, s, (H3)2. 13C NMR (75. 6 MHz) : #-1. 1, 3-OSi (CH3) 3; 2.5, 1- OSi (CH3) 3; 21. 7, 2xCH3 ; 26.1, C1' and C1''; 26.8, t, J 21.5 Hz, C2' and C2''; 44.1, C2; 68. 3, C3; 81.1, C1. Mass spectrum: m/z 940 (M+, absent), 795 (8%), 703 (6), 375 (5), 149 (5), 147 (28), 103 (82), 73 (100).

1. Examples of methods used for acetalation Use of polyfluorinated diol 1 (formula I : X = O; n = 1; R1 = R2 = R4 = R5 = R6 = R9 = H ; R3 = -CH2CH2C6F13)18 in the preparation of acetals and ketals 7-12.

(a) Method 1 : Diol 1 and carbonyl compound (1, 1 mol equiv) were dissolved together in toluene (20 L per mol). p-Toluenesulfonic acid monohydrate (0. 1 mol equiv) was added and the mixture refluxed in a Dean-Stark apparatus for 20 h under argon. The solution was cooled, washed with 10% aqueous KxCOs solution, dried, evaporated under vacuum. The resulting solid was normally chromatographed on silica gel using a gradient of Et20/light petroleum and the major product recrystallized.

(b) Method 2 : Diol 1 and carbonyl compound (1. 1 mol equiv) were dissolved together in toluene (20 L per mol). Pyridinium p-toluenesulfonate (PPTS) (0. 1 mol equiv) was added and the mixture refluxes a Dean-Stark apparatus for 20 h under argon The solution was cooled, washed with 10% aqueous K2CO3 solution, dried, evaporated under vacuum. The resulting solid was normally chromatographed on silica gel using a gradient of Et2O/light petroleum and the major product recrystallized.

(c) Method 3: Diol 1 and carbonyl compound (1.0 mol equiv) were dissolved together in BTF (20 L per mol) and Amberlyst 15 resin (126 g per mol) and 4A molecular sieves (4.2 kg per mol) were added and the mixture stirred for 20 h at room temperature. The resulting mixture was filtered and the residue of molecular sieves was washed well with Et2O. The filtrates were combined and evaporated under vacuum, and the resulting solid chromatographed on silica gel using a gradient of Et2O/light petroleum and the major product recrystallized.

(d) Method 4 : Diet 1 and carbonyl compound (1.0 mol equiv) were dissolved together in cyclohexane (20 L per mol) andp-toluenesulfonic acid monohydrate (0.7 mol equiv.) and 4A molecular sieves (4. 2 kg per mol) were added. The mixture was stirred for 20 h at room temperature then filtered and the residue of molecular sieves washed well with Et2O. The filtrates were combined, washed with 10% aqueous KzCOs solution, dried and evaporated under vacuum, and the resulting solid chromatographed on silica gel using a gradient of St2 (;)/light petroleuin and the major product recrystallized.

It has been noted that aldehydes react more readily than ketones. Methods 1 and 2 proceed to completion with aldehydes and ketones. Method 4 proceeds well with aldehydes but less well with ketones while Method 3 is satisfactory for both aldehydes and ketones.

The same four methods are suitable for use in the preparation ofacetals and keta ! s from a wide range of polyfluorinated diols, including 2 (formula I : X = O; n = 1; R1 = R2 = R 5 = R6 = R9 = H; R3 = R4 = -CH2CH2C6F13), 3 (formula 1 : X = 0 ; n = 1 ; R'= R2 = R9 = H; R3 = R4 = CH3; R5 = R6 = -CH2CH2C6F13), 5 (formula @: X = 0 ; ri = 0; R1 = R2 =

R9 = H; R5 = R6 = -CH2CH2C6F13), and 6 (formula 1 : X = O; n = 2; R1 = R2 = R3 = R4 = R9 = H; R5 = R6 = -CH2CH2C6F13).

2. Examples of highlw fluorinated derivatives The following acetals and ketals are representative of those capable of formation by Methods 1-4, Neither the compounds themselves nor the methods by which they are prepared should be construed as limiting the invention in any way.

Derivatives prepared from polyfluorinated diol 1 (formula I: X = O; n = 1; R1 = R2 = R4 = R5 = R6 = R9 = H; R3 = -CH2CH2C6F13)18 5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane -2-spirocyclopentane 7 Prepared from diol 1 and cyclopentanone by Method 1 as an oil in 70% yield b. p. 100°C/0. 07 mmHg (Found : C, 39. 78; H, 3.79. C16H17F13O2 requires : C, 39. 36 ; R 3.51%). 1H NMR (300 MHz, CDCl3): # 1.58, m, (H1')2 ; 1. 66, m, (H2'')2 and (H3") 2 ; 1. 81, m, H5; 1.88, m, (H1'')2 and (H4'')2; 2.07, br m, (H2')2; 3.55, dd, J 12. 1, 8. 3 Hz, Ha4 and Ha6; 3. 93, dd, J 12.1, 7.9 Hz, H, 4 and H, 6.

Trans- and cis-2-phenyl-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoroocytl )-1,3-dioxane 8 Prepared from diol § and benzaldehyde as a 58: 42 mixture of trahis and cis diastereoisomers in 95% yield by Method 2 using toluene as solvent and 80% yield by Method 4. Chromatography gave trans-2-phenyl-5-(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-dioxane 8 m.p. 77-79°C (Found: C, 42.24; H, 3.32. CisHisFuO2 requires : C, 42.37; H, 2.96%). 1H NMR (300 MHz, CDCl3): # 1.45, m, (Hl') 2 ; 2, 05, br m, (H2')2 ; 2. 16, m, H5 ; 3. 59, dd, J 11.3, 11.3 Hz, Hax4 and Hax6; 4. 27, dd, J 11.7, 4. 5 Hz, He@4 and Heq6; 5,43, s, H2 ; 7. 35, m, 3 ArH; 7. 47, m, 2 ArH''. 13C NMR (75. 6 NIH7, CDCl3) : 0 18. 8, Cl' ; 28. 1 C2'; 33. 5, C5 ; 71. 7, C4 and C6 ; 101.6, C2 ; 125.9, C2'' and C6"or C3"and C5''; 128.2, C3'' and C5'' or C2'' and C6''; 128.9, C4'' ; 138. 0, Cl".

Mass spectrum : m/z 510 (M+, 4%), 509 (M-1, 8), 433 (2), 107 (38), 105 (100), 79 (19), 77 (34), 55 (14). The cis isomer could not be fully separated from its trans isomer.

2-methyl-2-phenyl-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro octyl)-1,3-dioxane 9 Prepared Sont diol J and acetophenone as a 67 : 37 mixture of t s and cis diastereoisomers m 84% yield by Method 1 with toluene as solvent and as a 59; 41 mixture of the same isomers in 74% yield by Method 3. The mixture was chromatographed on silica gel to give in-order of elution r-2-methyl-2-phenyl-c-5- (3, 3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane trans-9 as white flakes m. p.

92-93. 5°C (petroleum) (Found : C, 43. 60 ; H, 3. 30. C18H17F13O2 requires: C, 43.52; H, 3. 27%). 1H NMR (300 MHz, CDCl3) : # 1. 22, m, (H1')2 ; 1.52, s, 2-CH3; 1.99, br m, (H2') ; 2.. 08, m, HS ; 3.40, dd, J 11. 3,11. 3 Hz, Hax4 and Hax6 ; 3. s dd, J 11. 3,4. 5 Hz, Heq4 and Heq6; 7.33, m, 1 ArH ; 7. 38-7.44, m, 4 ArR."C NMR (75. 6 MHz, CDCl3): # 18.8, C1'; 27. 9, C2'; 32.0, C1''; 33. 6, C5 ; 65.8, C4 and C6 ; 100. 6, C2 ; 126. 6, C2"'and C6''' or C3''' and C5'''; 127.7, C4'''; 128. 7, C3"'and C5''' or C2''' and C6'''; 140. 4, Cl'".

Mass spectrum : mlz 512 (M, absent), 509 (5%), 447 (4), 149 (6), 121 (12), 105 (100), 91 (7), 77 (28), 69 (21), 43 (37); and r-2-methyl-2-phenyl-t-5-(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-dioxane cis-9; which could not be fully separated from the irans isomer. 1H NMR (300 MHz, CDCl3): # 1.32, m, H5 ; 1.51, s, 2-CH3; 2.07-2.20, m, (H1') 2; 2.15-2.32, br m, (H2')2; 3.69, dm, J 11. 7 Hz, Hax4 and Hax6 ; 3. 94, dm, J 11. 7 Hz, Hcq4 and Heq6; 7.31, m, 1 ArH; 7.37-7.46, m, 4 ArH. 13C NMR (75.6 MHz, CDCl3): # 20. 1, Cl' ; 28. 2, C2' ; 31. 6, Cl" ; 33.2, C5 ; 64.0, C4 and C6 ; 100. 8, C2; 126.5, C2''' and C6''' or C3''' and C5'''; 127. 7, C4'''; 128.6, C3''' and C5''' or C2''' and C6'''; 140. 7, C1'''.

2, 2-diphenyl-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)- 1,3-dioxane 10

Prepared from diol 1 and benzophenone in 64% yield by Method 1 using toluene as solvent. White flakes m.p. 70. 5-72°C (petroleum) (Found : C, 48. 86; H, 3.56.

C24H19F13O2 requires: C, 49.16 ; H, 3.27%). 1H NMR (300 MHz, CDCl3): # 1.62, m, (Hl') 2 ; 1. 96, r, H5; 2.09, br m, (H2')2; 3.70, dd, J 11.7, 7.9 Hz, Hax4 and Hax6; 4.09, dd, J 11.7, 4.1 Hz, Heq4 and Heq6; 7.20-7.39, m, 6 ArH; 7.50, m, H2'', H2''', H6'' and H6'"."C NMR NMR (75.6 MHz, CDCl3): # 19.3, C1'; 28. 2, t, J22. 5Hz, C2'; 33.6, C5 ; 65. 5, C4 and C6; 101. 2, C2 ; 126. 0 and 126.7, C2'' and C6'' and C2''' and C6''' or C3"and C5'' and C3'"and C5" ; 127. 8 and 127. 9, C4"and C4'''; 128.2 and 128. 5, C2"and C6"and C2''' and C6''' or C3'' and C5'' and C3''' and C5'''; 142.5, C1'' or C1'''. Mass spectrum: 7nez 626 (MF, absent), 510 (10°ro), 509 (55), 182 (25), 165 (10), 154 (8), 123 (8), 105 (100), 77 (65), 55 (15).

2, 2-diethyl-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1 ,3-dioxane 11 Prepared from diol 1 and 3-pentanone in 73% yield by Method 3 as solvent.

Colourless oil b. p. 100°C/0. 1 mmHg (Found: C, 39. 15; H, 4,25. C16H19F13O2 requires : C, 39. 20; H, 3. 91%). 1H NMR (300 zu CDCl3: # 0.87, t, 2-CH2CH3; 1.55-1.80, m, (H1') 2, H5, 2-CH2CH3 ; 2. 05, br m, (H2')2 ; 3. 58, dd, J 11.7, 4.5 Hz, Heq4 and Heq6; 3.92, dd, J 11. 7,7. 5 Hz, Hax4 and Hax6. 13C NMR (75. 6 MHz, CDCl3): # 7.3, Cax2''; 7.4, Ceq2'''; 19.4, t, J4.4, 3 : 6. Hz, C1'; 24.4, Cax1''; 26.9, Ceq1'''; 28.2, t, J22.5 Hz, C2'; 33.4, C5; 63. 2, C4 and C6; 101. 2, C2. Mass spectrum : mlz 490 Oe, absent), 461 (20%), 169 (2), 127 (3), 87 (20), 69 (10), 57 (100), 55 (8), 41 (10).

2-(3-hydroxylphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-trideca fluorooctyl)-1,3-dioxane 12 Prepared from diol 1 and 3-hydroxybenzaldehyde as a 63 37 mixture of trans- and cis-diastereoisomers in 83% yield by Method 2 and as a 93:7 mixture of the same isomers in 83% yield by Method 4. White flakes m. p. 118-119°C (petroleum) (Found; C, 40.95; H, 2.82. C18H15F13O3 requires: C, 41.08 ; H, 2. 87%). 1H NMR (300 MHz): # 1. 42, m, (m') 2 ; 2. 06, m, (H2')2 2 ; 2. 14, m, H5; 3. 58, dd, J 11. 3, 11.3 Hz, Hax4 and Hax6;

4. 26, dd, J11.7, 4.5 Hz, Heq4 and Heq6 ; 4. 87, br s, OH; 5.38, s, H2; 6.82, dd, J7.9, 2. 3 Hz, H4''; 6. 96, S, H2' ; 7.02, d, J7.5 Hz, H6''; 7.22, dd, J7.9, 7. 5 Hz, H5''. 13C NMR (75. 6 M) : ci 18.8, C1'; 28.0, t, J22. 9 Hz, C2' ; 3 3. 5, C5 ; 71. 7, C4 and C6; 101. 1, C2; 112.9, C2''; 115. 9, C4''; 118. 4, C6''; 129.6, C5'' ; 139. 6, C1''; 155. 5, C3". Mass spectrum : m/z 526 (M+, 4%), 509 (2), 123 (18), 122 (71), 121 (100), 94 (30), 77 (20), 9 (33), 65 (37), 55 (48).

Derivatives prepared from polyfluorinated diol 2 (formule 1 : X = 0 ; n = 1 ; R1 ruz = R = R4 = -CH2CH2C6F13). 5, 5-E,'is (3, ', 4, V, 5, 5, d, õ, i', 7, 8, 3, 8-decaflvorooc4blJ-2-et1-', 3^ xXe 13 CeF13zZ 2eft3 6 r"") 4 6Cm4 o A - : XH 1 Ill. I Diol 2 and propionaldehyde were treated by Method 3 to give 2-ethyl-5,5- bis (3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane 61 as a colourless oil (0. 187 g, 96%). vmax 2948, 2851, 2774, 2726, 2665, 1728, 1474, 1461, 1366, 1317, 1240, 1196, 1146, 1122, 1070, 708. 1H NMR (300 MHz) : q 94, t, J7.5 Hz, CH2CH3 ; 1. 36, m, CH2CH3; 1. 64, m, (H2')2; 1.99, m, (H1')2 and (H1'')2; 2.16, br m, (H2'')2; 3.50, d, J11.3 Hz, Hax4 and Hax6; 3. 79, d, J11.7 Hz, Heq4 and Heq6 ; 4. 40, t, J4. 9 Hz, H2. , 8, 8, 8-trid--cajyuoroociyl)-2-phenyl-1. 3-&oxan 14 C6F3) T 1'"", wJ 1 6 () 4 7. 0 0" 14 (i) Diol 2 and benzaldehyde were treated by Method 2 to give a yellow oiJ that was column chromatographed on silica gel and recrystallized from light petroleum to give 5,5-bis(3,3,4,4,5,5, 6, 6, 7,7,8,8,8-tridecafluorooctyl)-2-phenyl-1,3-dioxane 14 as white needles (70%) m. p. 60-6I°C (Found : C, 36. 36 ; II, 2. 20. C26H18F26O2 requires : C, 36. 47 ; H, 2. 12%). 1H NMR (300 MHz) : #1.45, m, (H1')2; 2.05, m, (H2')2; 2.11, m, (H1'')2; 2.17, ni, (H2'') 2 ; 3. 74, d, J 11. 7 Hz, Hax4 and Hax6; 3.96, d, J 11.7 Hz, Heq4 and Heq6; 5,44, s, H2; 7.39, m, H2''', H4''' and H6'''; 7.45, m, H3''' and H5'''. 13C NMR (75. 6

MHz): # 21.7, Cl" ; 22. 9, C1'; 24. 3, t, J22.9 Hz, C2'; 25. 7, t, J22.2 Hz, C2''; 33.4, C5; 74.1, C4 and C6 ; 102.2, C2; 126.0, C3''' and C5'''; 128. 3, C2'"and C6'''; 129.1, C4'''; 137.5, C1'''. Mass spectrum: m/z 855 (M-', 40/o), 401 (5), 373 (2), 327 (2), 149 (5), 131 (6), 123 (17), 105 (100), 97 (20), 91 (32), 79 (35), 77 (45), 69 (72).

(ii) Diol 2 and benzaldehyde were treated by Method 3 to afford 5, 5- bis(3,3,4,4,5,5,6,6,7, 7, 8, 8,8-tridecafluorooctyl)-2-phenyl-1,3-dioxane 14 in 89% yield.

Derivatives prepared from polyfluorinated diol 3 (formula I : X = O; n = 1; R1 = R2 = R9 = H; R3 = R4 = CH3; R5 = R6 = -CH2CH2C6F13) 5,5-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-(3-h ydroxyphenyl)-1,3-dioxane Diol. 2 and 3-hydroxybenzaldehyde were treated by Method 2 to afford 5, 5- bis (3) 3, 4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-(3-hydroxyphenyl )-1,3-dioxane 15 as white ilakes (0, 432 g, 91%) m. p. 106-108°C (Found : C, 35. 90 ; H, 2. 13. C26H18F26O3 requires : C, 35. 80; H, 2.08%). 1H NMR (300 MHz) : LI 1.45, m, (H1')2; 1.98, M, (H2')2; 2. 07, m, (H1'')2 2 ; 2. 20, m, (H2'')2; 3.72, d, J11. 7 Hz, Hax4 and Hax6; 3. 95, d, J 11. 7 Hz, Heq4 and Heq6; 4.86, br s, OH ; 5, 39, s, H2; 6.83, dd, J 7. 9, 2.6 Hz, H4'" ; 6.94, dd, J2. 3, 1. 5 Hz, H2"' ; 7. 02, d, J 7. 5 Hz, H6'''; 7. 25, dd, J7. 9, 7.5 Hz, H5'"."C NMR (75. 6 NIEZ) : O 21. b, C1''; 22. 8, Cl' ; 24.3, t, J22.2 Hz, C2'; 25.6, t, J21.1 Hz, C2''; 33. 4, C5 ; 74. 1, C4 and C6 ; 101. 8, C2; 112. 9, C2''' ; 116. 1, C4'" ; 118. 5, C6"§ ; 129. 7, C5'''; 139. 1, C1'''; 155. 5, C3"'. Mass spectrum : Dilz 872 (M+, 3%), 871 (4), 855 (2), 779 (1), 401 (3), 373 (3), 327 (2), 219 (5), 167 (8), 149 (30), 123 (63), 122 (100), 121 (94), 95 (35), 81 (51), 69 (90).

4,4-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-5,5 -dimethyl-2-ethyl-1,3-dioxane 16

Diol 3 and propionaldehyde were treated by Method 3 to give 4- bis (3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-5,5-dimethyl- 2-ethyl-1,3-dioxane 16 as a colourless oil (94%), #max 2972, 2884, 1471, 1398, 1367, 1317, 1240, 1196, 1145, 1053, 707. 1H NMR (300 MHz): # 0.77, s, (CH3)ax; 0.91, t, J7.5 Hz, CH2CH3; 1. 22, s, (CR) eq ; 1.63, m, CH2CH3; 1.63, 1.79 and 2. 46, in, (H1')2 and (H1'')2 ; Z. 12, br m, (H2')2 and (H2") ; 3.36, d, J11.7 Hz, Hax6; 3.79, d, J12.1 Hz, Heq6; 4.52, t, J4.9 Hz, H2. 13C NMR (75.6 MHz, CDCl3): #7.8, CH2CH3; 20.2, (CH3)ax; 20.9, C1'; 22.9, (CH3)eq; 24.6, t, J21.8 Hz, C2'; 24. 9, Cl" ; 26. 7, t, J22. 2 Hz, C2''; 27.9, CH2CH3 ; 36. 2, C5 ; 74. Z C6 ; 77.0, C4 ; 99. 4, C2. Mass spectrum ; m/z 836 (M+, absent), 761 (5%), 489 (2), 431 (8), 387 (6), 375 (12), 119 (3), 85 (15), 69 (8), 57 (39), 56 (100).

- 4,4-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-5,5-di methyl-2-phenyl-1,3-dioxane 17 (i) Diol 3 and benzaldehyde were treated by Method 2 to give a mixture of white solid and colourless oil (0. 269 g) that was adsorbed on to fluorous reverse phase silica geld and the gel loaded on to a chromatography column. The column was flushed with 70:30 MeOH/H2O then light petroleum. The fraction from light petroleum was column chromatographed on silica gel to yield 4,4-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-5,5-dimethyl-2-phenyl-1,3-dioxane 17 as a colourless oil (85%) b. p.

175°C (oven)/0. 4 mmHg (Found: C, 38. 32 ; H, 2.70 C28H22F26O2 requires: C, 38.03 ; H, 2.51%). vmax 3071, 3038, 2865, 1474, 1397, 1316, 1240, 1196, 1145, 1101, 1019, 746, 735, 708, 698. 1H NMR (300 MHz) : 00. 86, s, (CH3) ax; 1.36, s, (CH3)eq; 1.78, m, Ha1'; 1. 89, ni, (H1'') 2 ; 2. 20, br m, (H2')2 and (H2'')2; 2. 63, m, Bol ; 3. 54, d, J12.1 Hz, Hax6; 4. 02, d, J12. 1 Hz, Heq6 ; 5,54, s, H2; 7. 40, m, 5xArH. 13C NMR (75. 6 MHz): # 20.4, (CH3) ax ; 20. 8, Cl' ; 23.0, (CH3) eq; 24.8, t, J20.3 Hz, C2'; 25. 1, C ; 26.3, t, J21.8 Hz, C2" ; 36. 2, C5; 74. 7, C6; 78. 4, C4 ; 95. 5, C2 ; 125. 9, C3''' and C5'''; 128.3, C2''' and C6'''; 129. 1, C4'''; 138. 0, Cl"'. Mass spectrum : m/z 884 (M+, 2%), 761 (2), 431 (4), 375 (4), 162 (5), 149 (6), 123 (8), 107 zoo), 105 (27), 56 (34).

(ii) Diol 3 and benzaldehyde were treated by Method 3 to, give acetal 17 in 88% yield.

4,4-Bis(3,3, 4, 4, 5, 5, 6, 6,7,7,8,8,8-tridecafluorooctyl)-2-phenyl-2,5,5-trimethyl-1,3 - dioxane 18

Diol 3 (0.241 g, 0.30 mmol) and acetophenone (0. 046 g, 0. 38 mmol) were treated by Method 2 with PPTS (0. 013 g, 0.05 mmol) as catalyst to give a colourless oil (0. 271 g) that was separated on silica gel. The fraction from 5: 95 Et20/light petroleum was evaporated to afford crude 4,4-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2- phenyl-2,5,5-trimethyl-1,3-dioxane 18 as a colourless oil (0. 034 g, 12%).'H NMR (300 MHz) : Q0. 83, s, (CH3)ax; 1. 24, s, (CH3) eq; 1.54, s, CH3, 1.80-2,27, br m, (H1'')2, (H1')2, (H2')2 and (H2'') 2; 3. 48, d J 11. 7 Hx, tE ; 3.92, d, J 11.7 HA Hzq6 ; 7. 30, m, 3xArH 7. 42, m, 2xArH.

4,4-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-5,5 -dimethyl-2-(3-hydroxyphenyl)- J, 3-dioxine 19 9g Diol 3 and 3-hydroxybenzaldehyde were treated by Method 2 to afford 4, {- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-5,5-dimeth yl-2-(3-hydroxyphenyl)-1,3- dioxane 19 as white flakes (91%) m. p. 73-74°C (light petroleum) (Found: C, 37. 38 ; H, <BR> <BR> 2. 51. C28H22F26O3 requires: C, 37.35; H, 2.465). 1H NMR (300 MHz): #0.85, s, (CH3)ax; 1.35, s, (CH3)eq ; 1. 78, ddd, J 15. 1, 10. 2, 4. 9 Hz, Ha1'; 1.89, t, J8.6 Hz, (H1'')2; 2, 0 38, m, (H2') 2 and (H2'')2; 2.61, ddd, J15. 4,11. 6, 4.5 Hz, 1-1l' ; 3.53, d, J11. 7 Hz, Hax6; 4.00, d, J 11.7 ¢ I-L,, ; 4, 84, br s, OH, 5.49, s, H2 ; 6. 83, dd, J7.9, 1.9 Hz, H4''' ; 6. 94, d, J 2.3 Hz, H2'''; 6.97, d, J7. 9 Hz, H6'''; 7. 25, dd, J7.9, 7. 9 Hz, H5'''. 13C NMR (75. 6 MHz) : D 20. 4, (CH3)ax; 20.7, C1'; 23.0, (CH3)eq; 24.8, t, J 22. 2 Hz, C2'; 25. 1, C1"; 26. 3, t, J22.5 Hz, C2''; 36.2, C5 ; 74. 6, C6; 78.5, C4; 95.1, C2; 112.8, C2'''; 116.1, C5'''; 118.4, C6'''; 129.7, C4'''; 139.7, C1'''; 155.6, C3'''. Mass spectrum : m/z 901 (M-M, trace), 415 (11%), 375 (7), 139 (12), 123 (45), 122 (100), 121 (41), 95 (13), 69 (25).

Derivatives prepared from polyfluorinated diol 5 (formula I : X = O; n = 0 ; R-R-R = H ; R5 = R6 = -CH2CH2C6F13) 4 4-Bis (3, 3, 4, 4, 5,. 5, 6, 6, 7, 7, 8, 8, 8-t-deca c S 6F13 z, 2 @S) S 2"' CH- 20 (i) Diol 5 and benzaldehyde were treated by Method 2 to give 4,4- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-phenyl-1 ,3-dioxolane 20 as a colourless oil (70%) b. p, 165°C (oven)/0.5 mmHg (Found: C, 35.70 ; R 1. 97.

C25H16F26O2 requires: C, 35. 65 ; R 1.91%). vmax 3041, 2960, 2878, 1456, 1366, 1317, 1240, 1209, 1145, 1069, 732, 708, 699. 1H NMR (300 MHz): # 2.00, br M, (H1')2 and (H1'')2 ; 2. 22, br m, (H2') 2 and (H2'')2; 3.86, d, J 8. 7 Hz, Ha5 ; 4. 02, d, J 9. 0 Hz, Hb5 ; 5. 90, s, H2; 7.40, m, 5xArH. 13C NMR (75. 6 MHz): #25. 8, t, J22.2 Hz, C2' and C2''; 27. 5, Cl' ; 27. 7, Cl" ; 73. 6, C5 ; 80.4, C4 ; 104. 1, C2 ; 126.1, C2"'and C6'''; 128. 4, C3''' and C5'''; 129.5, C4'''; 136.5, C1'''. Mass spectrum: m/z 842 (M+, 13%), 720 (4), 495 (18), 401 (19), 375 (10), 327 (3), 131 (4), 123 (30), 107 (66), 105 (100), 91 (29), 78 (69). Unreacted 1,2-diol 5 (28%) was recovered as white solid.

(ii) Diol 5 and benzaldehyde were treated by Method 3 to give 4,4- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-phenyl-1 ,3-dioxalane 20 as a colourless oil (95%), which by GC was of 98% purity. a, 4-Bis(3,3,4,4,5,5,6,6, 7, 7, 8, 8, 8-tridecafluorooctyl)-2-methyl-2-phenyl-1,3-dioxolane 21 (i) Diol 5 and acetophenone were treated by Method 2 to give 4, bis(3,3,4,4,5,5,6,6,7, 7, 8,8,8-tridecafluorooctyl)-2-methyl-2-phenyl-1,3-dioxolane 21 as a colourless oil (11%) b. p. 170"C (oven)/0, 8 mmHg (Found: C, 36. 61 ; H, 2. 08.

C26H18F26O2 requires: C, 36.47 ; H, 2. 12%). vmax 2723, 1319, 1247, 1203, 1145, 1071, 1044, 697, 655. 1H NMR (300 MHz): # 1. 53-1. 73, m, (H1')2; 1.63, s, Chia ; 1. 75-2. 00, m, (H1'')2; 1.98, m, (H2')2 ; 2. 29, m, (H2'') 2 ; 3. 60, d, J9.1 Hz, Ha5; 3.92, d, J 9

Hb5 ; 7.34, m, H2''', H4''' and H6'''; 7. 43, m, H3''' and H5'''. 13C NMR (75.6 MHz): #25 8, C2'; 26. 0, C2" ; 27.5, C1'; 28.1, C1"; 28.8, CH3; 72. 7, C5 ; 81.1, C4; 110.5, C2 ; 124. 7, C2''' and C6'''; 128. 0, C4'''; 128.3, C3''' and C5'''; 143. 4, Cl'". Mass sectrum; m/z 856 (M+, absent), 841 (5%), 779 (1), 509 (3), 375 (3), 133 (17), 123 (22), 105 (100), 77 (18).

Unreacted 1, 2-diol 5 (87%) was recovered as a white solid.

(ii) Diol 5 and acetophenone were treated by Method 3 for 2 days to give 4,4- bis (3, 3,4,4,5,5, 6, 6,7,7,8,8,8-tridecafluorooctyl)-2-methyl-2-phenyl-1,3-dioxol ane 21 as a colourless oil (54%), and 1, 2-diol S (37%)-was recovered as a white solid.

4,4 Bis (3, 3, 4, 4, 5, 5, 6, 6,7,7,8,8,8-tridecafluorooctl)-2-(3-hydroxyphenyl)-1,3-dioxo lane 22 Diol 5 and 3-hydroxybenzaldehyde were treated by Method 2 to give 4 bis (3, 3, 4, 4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-(3-hydroxyphenyl)- 1,3-dioxolane 22 as a colourless oil (92%) b.p. 200°C (oven)/0.4mmHg (Found: C2 35.11; H, 1. 95.

C25H16F26O3 requires : C, 34: 98; H, 1.88%). 1H NMR (300 MHz): # 2.00, br m, (H1')2 and (Hl") 2 ; 2. 22, br m, (H2')2 and (H2")2 ; 3. 86, d, J 8. 7 Hz, Hu5; 4.00, d, J 8.7 Hz, Hb5; 4. 91, s, OH; 5.85, s, H2; 6.83, ddd, J 7. 9, 2. 6, 1. 1 Hz, H4'''; 6. 91, dd, J2. 2.2, 1.5 Hz, H2'" ; 7. 01, d, J 7.5 Hz, H6'''; 7. 26, dd, J-7. 9,7. 5 ha H5'''. 13C NMR (75. 6 MHz) : #25.8, t, J 22.2 Hz, C2' and C2''; 27.4, t, J 3. 6 Hz, C1'; 27. 7, t, . J3. 2144 Cl" ; 73 ; 5, C5 ; 80. 5, C4 ; 103. 7, C2; 113.0, C2'''; 116.4, C4'''; 118.5, C6'''; 129.8, C5'''; 138. 5, Cl'" ; 155.7, C3"'. Mass Spectrum; m/z 858 (M+, 0.9%), 857 (M-1+,1), 511 (3), 375 (4), 169 (3),1 39 (14), 121 (51), 94 (100), 77 (16), 65 (13).

Derivatives prepared from polyfluorinated diol 6 (formula f : X=O; n=2; R1=R2=R3 = R4=R9=H; R5=R6= -CH2CH2C6F13) 4, 4-bis(3,3,4,4,5,5,6,6,7, 7, 8, 8 8-tridecafluorooctyl)-2-phenyl-1,3-dioxepane 23 5 10 <BR> <BR> <BR> <BR> 15 20 25 (i) Diol 6 and benzaldehyde were treated by Method 2 to give 2, 2- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoroocty)tetrahydrofu ran 78 as a colourless oil (25%) b. p. 1 lOaC (oven)/0. 5 i3 5S 5 0 \-C6Fi3 78 (Found : C, 31. 56 ; H, 1.97. C20H14F26O requires : C, 31.43; H, 1.85%). vmax 2964, 2874, 1456, 1317, 1196, 1071, 847, 813, 746, 730, 708. 1H NMR (300 MHz) : #1. 83, m, at) 2, (H1')2 and (H1'')2; 1.98, m, J 7.2 Hz, (H4)2; 2. 16, br m, (H2')2 and (H2")2 ; 3.88, t, J 6. 8 Hz, (H5)2. 13C NMR 975.6 MHz): #26. 4, t, J 22.2 Hz, C2'and C2" ; 26.4, C4 ; 28.9, C1' and C1"; 35.3, C3 ; 68.4, C5 ; 82. 3, C2. Mass spectrum : mlz 764 (MF, absent), 723 (5%), 4 18 (10), 417 (100), 375 (34), 327 (5), 263 (5), 169 (6), 131 (8), 97 (24), 69 925) ; and 4,4-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-phen yl-1,3-dioxepane 23 as a colourless oil (8%) b. p. 170°C (oven)/0. 3mmHg (Found : C, 37.16 ; H, 2. 08.

C27H2O. requires : C, 37.26 ; H, 2. 32%). vmax 3069, 3036, 2958, 1456, 1366, 1316, 1190, 1114, 1056, 980, 812, 746, 697. 1H NMR (300 MHz); #1. 78-2. 40, m, (H5) 2.

(H6) 2, (H1')2, (H1")2, (H2')2 and (H2")2; 3.65, ddd, J 12.1, 10.2, 2.6 Hz, Hax7 ; 4. 16, ddd, 712. 1, 3. 8,3. 4 Hz, H. q7 ; 5,66, s, H2 ; 7. 30-7, 40, m, 5xArH. 13C NMR. (75. 6 MHz): #25.7, t, J22. 5 Hz, C2" ; 25.9, t, J 22. 5 Hz, C2' ; 26. 2, Cl' ; 27. 9, C1" or C6; 28.0, C6 or C1"; 37. 4, C5 ; 70. 5, C7 ; 77.7, C4 ; 97. 9, C2 ; 125.6, C2''' and C6'''; 128. 2, C3''' and C5'''; 128. 4, C4''' ; 139.6, C1'''. Mass spectrum : m/z 868 (M+, absent), 747 (4%), 4g3 (4, 417 (100), 375 (32), 147 (96), 119 (13), 105 (94), 77 (58).

Unreacted 1, 4-diol 6 (61%) was recovered.

(ii) Diol 6 and benzaldehyde were treated by Method 3 to give 4, d- bis(3,3,4,4,5,5,6,6, 7,7, 8, 8, 8-tridecafluorooctyl) 2-phenyl-1,3-dioxepane 23 as colourless oil (25%) and unreacted 1, 4-diol 6 as a white solid (73%).

3. Example of a method used for thioacetalation Use of polyfluorinated disulfide 24 (formula I: X = S ; n = 1 ; R1=R2 = R4=R5 = R6 =H;R3=CH2CH2C6F13; R9= single covalent bond between X groups) in the preparation of dithioacetal 25.

25 A solution ofBF3'OEt2 (0. 10 mL, 0. 6 nimol) and glacial AcOB (0.2 nL) in CHCl3 (1 mL) was stireed under reflux in an argon atmosphere for 15 min. A solution or 4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,2-dithiac yclopentane 24 (280 mg, 0.6 mmol) and dimethoxymethane (0. 054 mL, 0.61 mmol) in CHCl3 (1. 5 mL) was added over 15 min and the mixture refluxed for another 6 h. The reaction mixture was cooled) 20 (10 mL) added, the organic layer separated and the aqueous layer re- extracted with Et20 (2 x mL). The organic extracts were combined, washed with 10% KOH (10 mL) and dried (Na2SO4). Removal of the solvent and chromatography of the resulting yellow oil (23 0 mg) afforded from the 1% Et2O in light petroleum fraction, unreacted disulfide 24 (75 mg, 27%), and from the 5-10% Et2O in light petroleum fraction, 5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dithian e 25 as (54 mg, 19%) m. p. 68-70 C (ligh petrole) (Found : C, 30. 95; H, 2. 35. Ci2HjiFj3S2 requires : C, 30.91, H, 2.38%). 1H NMR (300 MHz, CDCl3): #1.70-1. 85 (2H, m, RFCH2CH2),1.90-2.00 (1H, m,-H2), 2.00 - 2.25 (2H, m, RFCH2CH2), 2.57 (1H, d, J <BR> <BR> 13.9 Hz, -CH2), 2.60 (1H, d, J 14.3 Hz, -CH2), 2.85 (2H, d, J 14.3 Hz, -CH2-), 3.60<BR> (1H, d, J 13.9 Hz, -CH2-), and 3.82 (1H, d, J 13.9 Hz, -CH2-). 13C NMR (75.5 MHz, (1H, d, J 13.9 HZ, -CH2-), and 3. 82 (1H, d, J 13. 9 Hz, -CH2-). 13C NMR (75. 5 Mus, CDCl3): # 25.11 (RFCH2CH2), 28. 02 (RFCH2CH2), 31.57 (-CH2-), 34.39 (-CH-) and 34.55 (2x -CH2-). Mass spectrum : m/z 466 (M+, 90%), 433 (8), 419 (20), 401 (10), 387 (15) and 375 (18).

4. Method for preparation of reactant 24 (formula I: X = S; n=1; R1=R2=R4=R5= R6=H; R3=CH2CH2C6F13; R9 = smg ! e covalent bond between X groups) (i) Synthesis of 2-(3,3,4,4,5,5,6,6,7,7,8,8-tridecafluorooctyl)prpopane-1,3-d iol dimesylate 26 '6F 13 5 OMsOMs 26 2- (3,3,4,4,5,5,6,6,7,7,8, 8, 8-Tridecafluorooctyl)propane-1,3-diol 1 (1. 00 g, 2. 36 mmol) and methanesulfonic anhydride (1.65 g, 9.44 mmol) were heated together at

100°C until they became miscible, whereupon conc H2SO4 (1 drop) was added and the mixture heated at the same temperature for 2 h. The reaction mixture was cooled, diluted with ice-water (25 mL) and extracted with Et2O (4 x 50 mL). The combined organic extracts were dried (Na2SO4) and evaporated to dryness to give a tan solid (1. 00 g) that was recrystallized from Et2O to give 2-(3,3,4, 4, 5, 5, 6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-propanediol dimesylate 26 sas colourless flakes (937 mg, 72%) (Found : C, 27. 08; H, 2. 39. C13H15F13O6S requires: C, 27. 00 ; H, 2.61%). 1H NMR (300 MHz, CDCII) : 0 1. 70-1. 90 92H, m, RFRCH2CH2), 2. 10-2. 30 (3H, m, RFCH2CH2, -CH), 3.06 (6H, s, 2 x CH3), 4.20-4.40 (4H, m, -CH2). 13C NMR (CDCl3, 75. 5 MHz): # 18. 18 (RFCH2CH2), 27.99 (RFCH2CH2), 37.39 (2 x CH3), 37.62 (C2), 67. 14 (2 x -CH2-). Mass spectrum : mlz 403 (23%), 367 (5), 205 (5), 175 (85), 135 (10), 111 (65), 97 (80), 79 (100) and 55 (60).

(ii) Synthesis of 2-(3,3,4,4,5,5,6,6,7, 7, 8, 8-tridecaSuorooctylpropane-1, 3-dithiol diacetate 27 27 Potassium thioacetate (59. 7 mg, 0.52 mmol) was added to a solution of 2- (3, 3, 4, 4, 5, 5, 6, 6, 7,7, 8, 8, 8-tridecafluorooctyl)-1,.3-propanediol dimesylate 26 (100 mg, 0. 17 mol) in DMF (2 mL) under argon and the mixture heated at 100-C for 20 h. The reaction mixture was cooled, the solvent removed under reduced pressure, the residue diluted with CHCl3, and the mixture filtered. The solid was washed several times with more CHC13, and the combined CHCl3 solutions washed with H2O (20 mL) and dried (Na2SO4). Removal of the solvent under vacuum gave an oil (100 mg), which was flash chromatographed. Elution with 40% Et2O in light petroleum gave 2- (3, 3, 4, 4, 5, 5, 6, 6, 7, 7,8,8-tridecafluorooctyl)propane-1,3-dithiol diacetate 27 as an orange oil (80 mg, 86 %) (Found: C, 33.50 ; H, 2. 86. C15H15F13S2O2 requires: C, 33.46, H, 2.81%). IR: #max 2930, 1694 (C=O), 1456, 424, 1354 cm-1. 1H NMR (300 MHz, CDC13) : 0 1. 60-1. 80 (2H, m, RFCH2CH2), 1.80-2.00 (1H, m,-H2), 2.00 - 2. 25 (2H, ni, RFCH2CH2), 2. 35 (6H, s, 2 x CH3COO), 2. 80-3, 10 (4E, m, -2 x CH2). 13C NMR (75.5 M CDCl3): # 22. 74 9RFCH2CH2), 28. 31 (RFCH2CH2), 30.44 (2 x CH3CO), 31.93 ( Z x S-CH2-), 38.13 (-CH-) and 194.92 (-CH3-C=O). Mass spectrum : m/z 538 (M+, 5%), 495 (100), 453 (92), 419 (40), 3 87 (8), 149 (20).

(iii) Synthesis of 4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,2-dithiac yclopentane 24

Sodium sulfide nonahydrate (166 mg, 0. 66 mmol) and sulfur (22 mg, 0.69 mmol) were added to dimesylate 26 (200 mg, 0.34 mmol) in dry DMF (10 mL) and the mixture heated at 1 00"C for 3 d. The reaction mixture was cooled and ice-water (15 mL) was added. The mixture was acidified with cone. HCl and extracted with EtsO (2 x 50 mL). The combined organic extracts were dried (Na2SO4), and the solvent removed in vacuum to give a yellow oil (143 mg). The oil was dissolved in Et2o (5 mL) and the solution added dropwise to a suspension of LiAlH4 (26 mg, 0. 69 mmol) in Etz4 (5 ml) under argon, and the mixture stirred for a further 48 h. The reaction mixture was cooled to 0°C and H2O (10 mL) and then 10% H2S04 (20 mL) added sequentially. The mixture was filtered through filter aid and the residue washed with Et20 (50 mL). The organic layer was separated and the aqueous layer extracted with more Et20 (50 mL). The combined organic extracts were washed with H20 (25 mL) and dried (Na2SO4).

Evaporation of the solvent gave a yellow oil (110 mg) which was subjected to repeated flash chromatography. Elution with 1% Et2O in light petroleum afforded 4- (3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,2-dithiacyc lopentane 24 as a yellow wax (45 mg, 29 %) (Found: C, 29. 46; H, 2.05. C11H9F13S2 requires: C, 29.22, H. 2.01%). 1H NMR (300 MHz, CDCl3): # 1.79-1.90 (2h, m, RFCH2CH2), 2.00-2.30 (2H, m, RFCH2CH2), 2.55-2 70 (1H, m, H2), 2, 75-2.90 (2H, m, CH2), 3. 20-3. 40 (ZR E-CH2-)- 13c NMR (75. 5 MHz, CDCl3); # 24.27 (RFCH2CH2), 29. 64 9RFCH2CH2), 43.62 (2 x CH2), 46. 28 (C2). Mass spectrum : m/z 452 (M+, 100%), 387 (33), 367 (8), 327 (8), 119 (5), 103 (2), 73 (38).

Examples of selectivity in acetal/ketal formation Reactions of 2,2-bis (3,3, 4, 4, 5, S, 6, 6,7,7,8,8,8-tridecafluorooctyl)-1,3-propanediol 2 (a) with 1S-(endo,endo)-3-acetyl-bicyclo[2.2.1]hept-5-en-2-ylcarboxal dehyde [Aldehyde versus ketone]

(i) Diol 2 (0. 227 g, 0. 30 mmol) and 1S-(endo,endo)-3-acetylbicyclo[2.2.1]hept-5-en-2- ylcarboxaldehyde-3-acetyl (0. 023 g, 0.14 mmol) were treated together by Method 2 with PPTS (0. 004 g, 0. 02 mmol) as catalyst to give a pale solid (0. 257 g) that was column chromatographed on silica gel. Elution with 10 : 90 Et20/light petroleum gave 1S-(endo,endo)-2-(5,5-bis(3,3,4,4,5,5,6,6,7, 7, $, 8, 8-tridecafluorooctyl)-1,3-dioxan-2- yl)-3-(2-methyl-5,5-bis(3,3,4,4,5,5,6,6, 7, 7, 8, 8, 8-tridecafluorooctyl)-1,3-dioxan-2- yl)bicyclo[2. 2. 1]hept-5-ene 28 as a white flakes (0. 108 g, 46%) m.p. 95-96°C (EtOH) (Found. C, 34.66 ; H, 1.98. C48H36F52O4 requires: C, 34. 63 ; H, 2.18%). 1H NMR (300 MHz): #1. 24, d, J 8. 7 Hz, H a7 ; 1. 33, m, (H1")2 or (H1v)2; 1. 44, s, CH3; 1. 45, m, IM and (Hl") 2 or (H1")2; 1.78, d, J 7. 9 Hz, Hb7; 1.86-2. 20, br ni, (H1''') 2 (H1vi) 2, (H2")2, (H2''')2, (H2v)2 and (H2vi)2; 2.29, m, H6; 2.91, br s, HI ; 3. 00, br s, H4; 3, 39, d, J 12. 1 Hz, Hax4' and Hax6'; 3.49, d, J 11.3 Hz, Hax4iv or HaX6iv; 3. 53, d, J 11.3 Hz, Hax6iv or Hax4iv; 3.72, d, J 11.3 Hz, Hcq4iv and Hcq6iv; 3. 77, d, J 12. 1 Hz, heq4' and Hcq6'; 4.04, d, J 6.4 Hz, H2' ; 6. 07, dd, J 5.3, 2. 6 Hz, H2 ; 6.20, dd, J 5. 3, 3.4 Hz, H3. 13C NMR (75.6 MHz) : 0 17. 1, CH3; 20.9, 218, 22.5, 22.9, Cl", Cl''', clv and Clvi; 24. 2,24. 3, 25. 4, 25. 7, C2", C2''', C2v and C2vi ; 33.1, C5'or C5" ; 33. 4, Ctiv or C5'; 43.6, Cl; 44.2, C4; 45.3, C6; 46. 7, C7 ; 51. 2, C5; 66.3 and 66.8, C4iv and C6iv ; 73. 8, C4'and C61; 100. 7, C2iv; 106. 1, C2'; 136. 0, C2 ; 137. 9, C3.

Further elution with 10 : 90 Et2O : light petroleum gave 1S-(endo,endo)-3-acetyl-2- (5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-d ioxan-2- yl)bicyclo[2.2.1]hept-5-ene 29 as a white solid (0. 034 g, 26%) that was recrystallized Som light petroleum as white flakes m.p. 117-117.5°C (Found: C, 37. 81 ; H, 2. 50.

C92H24F25O3 requires: C, 38.09 ; R 2. 65%). vmax 2728, 1699, 1321, 1247, 1209, 1185, 1140, 1119, 1062, 733, 698, HE (300 MHz): #1.35, m, Ha7 ; 1. 45, m, (H1")2 ; 1.52, m, Hb7; 2.05, m, (H2") 2; 2. 11, m, (H1''')2; 2.15, d, J 3. 4 Hz, H5 ; 2. 17, zu, (H2''')2; 2. 23, s, COCU, 2. 56, m, H6,2. 94, br s, H1 and H4 ; 3. 40, d, J 11. 7 Hz, Hax4' and Hax6''; 3.77, d, J 11. 7 Hz, Heq4' and Heq6'; 3.87, d, J 7.9 Hz, H2'; 6.09, dd, J 5.3, 2.6 Hz, m ; 6. 22, dd, J 5.6, 3.4, Hz, H3. 13C NMR (75.6 MHZ): # 21.7, Cl'''; 22. 9, Cl"; 24. 3, t, J

22. 5 Hz, C2"; 25.6, t, J 22.2 Hz, C2'''; 29.7, COCH3; 33. 4, C5' ; 43. 5, Cl or C4 ; 46. 2, C4 or Cl ; 46. 8, C7 ; 47. 4, C6 ; 53. 8, C5; 73, 5 and 73.7, C4'and C6' ; 105. 8, C2'; 135.7, C2 ; 136. 9, C3; 209.7, COCH3. Mass spectrum : mlz 914 (M+, absent), 805 (1%), 779 (1), 373 (1), 135 (9), 109 (12), 97 (25), 83 (36), 81 (49), 69 (100), 57 (65), 43 (73).

Initial diol 2 (0. 089 g, 39%) was recovered from the pure Et2O fraction.

NMR spectra were assigned through 1H-1H COSY, 1H-13C HMQC and dept 135 experiments.

(ii) Diol 2 (0-353 g, 0, 46 mmol) and 1S- (endo, endo)-3-aceytl-bicyclo [2.2. 1] hept-5-en- 2-ylcarboxaldehyde (0. 078 87 0. 47 tnmol) were treated by Method 2 with PPTS (0. 012 s 0.05 mmol) as catalyst to give 1S-(endo,endo)-2-(5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-dioxan-2-yl)-3-(2-methyl-5,5-bis(3,3 ,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-dioxan-2-yl)bicyclo[2.2.1]he[pt-5-en e 28 as a white soild (0. 327 g, 78%). The H spectrum of this substance was identical to that from part ere was no measurable signal Rom compound 29.

(b) with 3,4, 8,8a-tetrahydro-8a-methyl-1, 6 (2H, 7H)naphthalenedione (Wieland- Miescher ketone) etone versus unsaturated ketone] C6FI3-V 6F13 9 fu oW 30 Diol 2 (0. a 10 g, 0.14 mmol) and Wieland-Miescher ketone (0.027 g, 0. 15 mmol) were treated by Method 2 with PPTS (0.004 g, 0. 02 mmol) as catalyst to give a pale solid 0, 1 g) that was loaded on to FRY-SAPE cartridge. The cartridge was flushed with 70:30 MeOH/H2O then light petroleum. The fraction from light petroleum was evaporated under vacuum to afford a yellow oil (0. 250 g) that was column chromatographed on silica gel. The faction from 20 : 80 Et2O : light petroelum was combined and distilled under vacuum to give product 30 as a colourless oil (0. 068 g, 51%) 13C NMR (75.6 MHz): # 21.7; 22.6; 24.9, t J 22.2 Hz; 24. 9 ; 25. 0, t J 22. 5 Hz ; 27, 2; 29. 9 ; 33. 6 ; 35. 5 ; 38. 6; 46.9 ; 66. 4; 66.7 ; 98. 6 ; 122. 0 ; 138. 1 ; 214.4.

Initial diol 2 (0. 028 g, 25%) was recovered from the pure Et2O fraction.

(d) with 4-formylacetophenone [AMehyde /'. N/ ketone) 06FI3 I-, bfla 11" 0 31 O °. 1 Diol 2 (0. 502 g, 0. 65 mmol) and 4-formylacetophenone (0.102 g, 0.69 mmol) were treated by method 1 in toluene (30 mL) with PPTS (0.018 zu 0.07 mmol) as catalyst to give a pale solid (0.566 g) that was column chromatographed on silica gel. The major fraction, eluted with 3 : 97 Et20-light petroleum, was evaporated to dryness to give 5, 5- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-(4-ethan oylphenyl)-1,3-dioxane 31 as a white solid (0. 488 g, 83%). The solid was recrystallized from light petroleum to give white needles m. p. 83-84°C (Found : C, 37. 24; H, 1.95. C28H20F26O3 requires: C, 37. 43; H, 2.24%). 1H NMR (300 MHz): #1.44, m, (H1')2; 2.05, m, (H2')2 ; 2. 10, m, (Hl")2 ; 2. 18, m, (H2")2; 2.60, s, COCH3; 3.75, d, J 11.7 Hz, Hax4 and Hax6; 3.98, d,, J 11. 7 Hz, Heq4 and Heq6 ; 5. 48, s, H2 ; 7. US, d, J 8. 3 Hz, hand H6'''; 7.97, d, J 8.7 Hz, H3'''a nd tit, 13C NMR (75.6 MHz): #21.7, C1"; 22.8, C1'; 24.3 t, J 22.5 Hz, C2'; 25.6, t, J 22.2 Hz, C2" ; 26. 6, COCH3; 33.5, C5 ; 74.2, C4 and C6, ; 101.3, C2; 126.3, C2''' and C6"' ; 128. 3, C3.. and C5"' ; 137. 6, C4'''; 142.0, C1'''; 197.6, COCH3. Mass spectrum : mlz 898 (M+, 1%), 883 (1), 855 (1), 779 (1), 401 (5), 165 (15), 149 (100), 133 (52), 104 (31), 69 (43).

Initial diol 2 (0. 083 g, 17%) was recovered from the pure Et2O fraction.

5,5-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-( 2-phenyl-(E)-ethenyl)-1,3- dioxane 3 ?,

Diol 2 (0. 625 g, 0.81 mmol) and cinnamaldehyde (0.169 g, 1.28 mmol) were treated by method I with PPTS (0. 028 g, 0. 09 mmol) as catalyst to give a pale gel (0.774 g) that was loaded on to a Silica gel column. The fluorous column was eluted with 70 : 30 MeOH : Hz0 then light petroleum. The fraction from light petroleum was recrystallized from light petroleum to give 5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-(2- phenyl-(E)-ethenyl)-1,3-dioxane 32 as white flakes (0. 704 8% 98%) m. p. 78-79'C (Found: C, 38. 05; H, 2.35. C28H20F26O2 requires: C, 38. 11 ; H, 2.28%). 1H NMR (300 MHz): # 1. 41, m, (H1')2; 2.02, br m, (H2')2 ; 2.05, m, (H1'') 2; 2.15, m, (H2'')2; 3. 63, d, J 11.7 Hz, Hax4 and Hax6; 3.89, d, J 11. 7 Hz, Heq4 and Heq6; 5. 07, d, J 4.9 Hz, H2; 6.18, dd, J 16.2, 4. 9 Hz, H1'''; 6.78, d, J 16. 2 Hz, H2'''; 7. 32, m, 3xArH ; 7.39, m, 2xArH. 13C NMR (75. 6 MHz): #21.7, C1''; 22.9, C1'; 24.3, t, J 22.5 Hz, C2'; 25.6, t, J 21. 8 Hz, C2"; 33.4, C ; 73. 8, C4 and C6 ; 101. 4, CZ ; 124.5, C1'''; 126.8, C2iv and C6iv; 128. 3, C4iV ; 128.5, C3iv and C5iv; 134. 0, C2'''; 135.7, C1iv. Mass spectrum: m/z 882 (M+, 6%), 387 (3), 256 (2), 149 (16), 133 (31), 132 (35), 131 (75), 107 (36), 104 (100), 81 (29), 69 (83). (d) with terephthalaldehyde [single versuv two-fold reaction with a dialdehyde] CeFis--y. eFl3 r, 1"' , 4' GF3A., sFi3 ia 6FI3 4 O" ... v. F, 1 X4 X H in . d4l 6 Ils 33 34 (i) Diol 2 (0. 113 g, 0. 15 mrnol) and terephthalaldehyde (0. 042 g, 0.31 nimol) were treated by Method 2 with PPTS (0.004 g, 0. 02 mol) as catalyst to give an off-white solid (0. 108 g) that was adsorbed on to a column of FRP-silica gel. The fluorous column was eluted sequentially with 70 : 30 MeOH/H2O, MeOH and Et2O. The fraction from MeOH gave 4-[5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3 - dioxane]benzaldehyde 33 as a white solid (0. 019 g, 15%) that was recrystallized from light petroleum as a white powder m. p. (Found : C, 36.73 ; R 1. 97. C27H18F26O3 requires : C, 36.67 ; R, 2.05%). vmax 1706, 1240, 1208, 1143, 1076, 710. 1H NMR (300 MHz): #1.44, m, (H1')2; 2.05, m, (H2')2; 2.09, m, (H1'')2; 2.20, m, (H2'') 2 ; 3.76, d, J 11.7 Hz, Hax4 and Hax6; 3.99, d, J 11. 7 Hz, Hm4 and Heq6; 5.50, s, H2 ; 7. 64, d, J 7. 9

Hz, H2'"and H6'" ; 7.91, d, J 8. 3 Hz, H3'''and H5'''; 10. 04, s, CHO. 13C NMR (75.6 MHz) : #21.7, C1''; 22. 7, Cl' ; 24. 3, t, J 22.9 Hz, C2'; 25.6, t, J 22.5 Hz, C2''; 33. 5, C5 ; 69. 8, C1iv; 74.2, C4 and C6 ; 101. 1, C2; 126. 7, C2'''and C6'''; J 29. 7, C3'''and C5'''; 136.8, C4'''; 143. 3, Cl'" ; 191. 8, CHO. Mass spectrum : m/z 884 (M+, 2%), 401 (8), 373 . (4), 167 (9), 149 (31), 135 (100), 133 (66), 105 (23), 69 (88), 55 (54).

Elution of the column with Et2O gave 1,4-bis[5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-1,3-dioxane]benzene 34 as a white solid (0. 08z, 34%) that was recrystallized from F-TOH to give white flakes m.p. 115-116°C (Found: C, 33. 57 ; H, 1. 58. C46H30F52O4 requires: C, 33.80 ; H, 1. .85%). vmax 1323, 1240, 1189, 1120, 1073, 1025, 704, 648. 1H NMR (300 MHz): #1. 45, m, (H1'') 2 and (H1vi)2 ; 1. 98, m, (H2'')2 and (H2vi)2; 2. 04, m, (Hl'") 2 and (H1v)2; 2. 17, ri (H2'") 2 and (H2v)2 ; 3. 73, d, J 11. 3 Hz, Hax4', Hax6', Hax4iv and Hax6iv; 3.96, d, J 11.3 Hz, Heq4', Heq6', Heq4iv and Heq6iv; 5.44, s, H2'and H2iv ; 7. 48, s, H2, H3, H5 and H 13C NMR (75.6 MHz): # 21.7, C1'', C1''', C1v and C1vi ; 25. 7, C2", C2"', C2v and C2vi; 33. 4, C5' and C5iv; 74.1, C4', C6', C4iv and C6'v ; 10 1. 7, C2'and C2'" ; 126. 0, C2, C3, C5 and C6 ; 13S. 4, CI and C4.

(ii) Diol 2 (0. 684 g, 0. 89 mmol) and terephthalaldehyde (0. 125 g, 0.93 mmol) were treated by Method 3 with Amberlyst 15 (0.219 g) as catalyst in BTF (10 mL) to give an off-white solid (0.795 g) that was subjected to chromatography on FRP-silica gel. The fluorous column was eluted sequentially with 70 : 30 MeOH : H2O, MeOH and Et2O.

The fraction from MeOH gave 4-[5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)- 1, 3-dioxcmeJbenzaldehyde 33 as a white solid (0.260 g, 33%). Elution with EtaO gave 1 ,4-bis[5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) -1,3-dioxane]benzene 34 as a white solid (0. 435 g, 30%). The 1H NMR and 13C NMR spectra of this substance were identical to those from part (i).

(iii) Diol 2 (0.684 g, 0.89 mmol) and terephthalaldehyde (0.125 g. 0.93 mmol) were treated by Method 3 with Amberlyst 15 (0.219 g) as catalyst in BTF (10 mL) to give an off-white solid 0. 795 g) that was chromatographed on FRP-silica gel. The fluorous column was eluted sequentially with 70 : 30 MeOH : H2O, MeOH and Et2O. The fraction from MeOH gave 5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2-(4- <BR> <BR> formylphenyl)-1,3-dioxane 33 as a white solid (0. 0.260 g, 82%). The elution from Et2O gave 1,4-bis[5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl )-1,3-dioxane]benzene 34 as a white solid (0.435 g, 6%). The 1H NMR and 13C NMR spectra of this substance were identical to those from part (i), Reaction of 1,1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-2,2-di methyl-1,3- propanediol 3 (a) with cinnamaldehyde [1,2- versus 1,4-addition]

(i) Diol 3 (0. 902 g, 1.13 mmol) and cinnamaldehyde (0.189 g, 1.43 mol) were treated by Method 2 with PPTS (0. 041 g, 0. 15 mmol) as catalyst to give a pale gel (1. 047 g) that was column chromatographed on silica gel, The major fraction, eluted with 5 : 95 Et2O : light petroleum, was recrystallized from light petroleum to give 4,4- bis(3,3,4,4,5,5,6,6,7, 7, 8, 8, 8-tridecafluorooctyl)-5,5-dimethyl-2-(2-phenyl-(E)-ethenyl)- 1, 3-dioxane 35 as white flakes (0.971 g, 95%) m. p. 74-75°C (Found: C, 39.38; H, 2. 76.

C30H24F26O2 requires : C, 39. 58; H, 2. 66%). vmax 1691, 1241, 1203, 1142, 1115. 1H NMR (300 MHz): # 0. 82, s, (CH3)ax; 1.30, s, (CH3)eq; 1.74, m, (H1')1; 1.86, m, (H1'')2; 2.16, br m, (H2')2 and (H2'')2; 2. 54, m, (H1') 1 ; 3.47, d, J 12. liez Hua 6; 3.79, d, J 12.1 Hz, Heq6; 5.16, d, J 4. 9 Hz, H2 ; 6.15, dd, J 15. 8,4. 9 Hz, H1'''; 6. 78, d, J 16.2Hz, H2'''; 7. 32, m, 3xArH; 7.39, m, 2xArH. 13C NMR (75. 6 MHz); #20.4, (CH3)ax; 20.9, C1'; 23.0, (CH3)eq; 24.8, t, J 17. 8 Hz, C2' ; 25. 0, C1''; 26. 2, t, J 22.2 Hz, C2''; 36.2, C5; 74. 4, C6; 78.0, C4; 94. 9, C2; 125.1, C1'''; 126.8, C2iv and C6iv; 128.3, C4iv; 128.5, C3iv and C5iv ; 133. 5, C2'''; 135.7, CliV. Mass spectrum : mlz 910 (M+, 5%), 761 (7), 563 (5), 431 (8), 401 (12), 387 (11), 150 (27), 131 (97), 104 (100), 69 (65).

(ii) Diol 3 (0.180 g, 0, 23 mmol) and cinnajnaldehyde (0.033 g, 0. 25 mmol) were treated by method 2 with Amberlyst 15 (0. 033 g) as catalyst in BTF (5 mL) to give acetal 35 as white flakes (0. 175 g, 85%) m.p. 74-75°C. The 1H NMR and 13C NMR spectra of this substance were identical to those of the product from method 1 (part (i)).

Applications of fluorous acetals (a) Protection during catalytic hydrogenation F13 7, 6 6 13 0 06Fl3 2" 36 Solid 10% Pd/C (0, 034 g) was added to a solution of unsaturated acetal 35 (0.121 g, 0.13 mmot) in EtOAc (10 mL) under argon. The mixture was stirred vigorously under

I2 for 24 h at room temperature, then filtered and the filtrate was evaporated to dryness to afford 4,4-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-5,5-di methyl-2-(2- phenylethyl)-1,3-dioxane 36 as a colourless oil (O. H5 g, 94%) b. p. 170°C (oven)/0. 6 mmHg (Found : C, 39.50; H, 2.92. C30H26F26O2 requires: C, 39. 49; H, 2. 87%). The oil comprised two diastereomeric components, which were evident in a ratio of 92 : 8 in the H NMR spectrum through the appearance of (H6)2 signals at #3. 40, 3. 79 and 3. 56, 4.02, respectively. vmax 3030, 2966, 2863, 1605, 1474, 1367, 1318, 1240, 1202, 1145, 1037, 707. 1H NMR (300 MHz, major isomer): #0. 77, s, (CH3)ax; 1.24, s, (CH3) eq; 1. 64, m, Ha1'; 1. 7$, m, (H1'') z ; 1. 96, m, (H1''')2; 2. 00-2. 28, br m, (H2')2 and (H2'')2; 2.39, m, Hb1'; 2. 70, t, J 8.1 Hz, (H2''')2 ; 3. 40, d, J 11.7 Hz, Hax6; 3.79, d, J 11.7 Hz, Heq6; 4.61, t, J 4.7 Hz, H2; 7.20, 3xArH; 7. 26, 2xArH. 13C NMR (75.6 MHz, major isomer) ; #20. 3, (CH3) ax ; 21.0, C1'; 22.9, (CH3)eq; 24. 7, t, J 21.8 Hz, C2; 24. 8, C1''; 26.2, t, J 21.8 Hz, C2''; 29.7, C2''', 36. 2, CS and C1'''; 74. 2, C6; 76.9, C4; 94.8, C2; 125. 9, C4' 128. 1, C2iV and C6iv; 128.3, C3iv and C5iv; 141. 2, C1iv. Mass spectrum: m/z 912 (M+, 1%), 761 (5), 431 (4), 415 (15), 375 (6), 134 (100), 107 (22), 105 (38), 92 (54), 69 (28).

(b) Protection during epoxidation Unsaturated acetal 35 (0. 082 zu 0. 09 mmol) in CH2Cl2 (6 mL) was added m- cbloroperoxybenzoic acid (O. 068 g, 0.39 mmol) at room temperature. The mixture was stirred at ambient temperature for 24 h, then evaporated under vacuum to dryness and column chromatographed on Fry-silica gel (5 g). The column was flushed with 70 : 30 MeOH/H2O then light petroleum. The fraction from light petroleum was evaporated to dryness to give 4,4-bis(3,3,4,4,5,5,6,6, 7, 7,8,8,8-tridecafluorooctyl)-5,5-dimethyl-2-(2- phenyloxiranyl)-1,3-dioxane 37 as a colourless oil (0.077 g, 93%), which by GC analysis was of 87% purity. The oil comprised two diastereomeric components, which were evident in the'H NMR spectrum in a ratio of 62: 38 through integration of the signals at 0 4. 54 and 4. 64, respectively. (Found: FAB-HRMS m/z 949.1258.

C30H24F26O3Na (M+Na) requires m/z 949. 1208). vmax 2970, 2867, 1730, 1478, 1366, 1317, 1240, 1202, 1145, 1110, 1050, 707, 698. 1H NMR (300 MHz) (major isomer): # 0.80, s, (CH3)ax; 3.82, s, (CH3)eq ; 1. 72, 1.85, 2.46, m, (H1')2 and (H1'')2; 2. 16, br m, (H2')2 2 (H2'')2 ; 3. 16, m, H1'''; 3. 47, dd, J 11. 7,9. 8 Hz, Hax6; 3. 85, dd, J 12. 1, 3. 8 Hz,

Sq6 ; 3. 81 and 3. 89, d, 1. 9 Hz, H2'''; 4. 54 and 4.64, d, 4. 3 Hz, H2; 7. 28, m, 2xArH; 7.32, ni, 3xArH. 13C NMR (75.6 MHz) (major isomer): #20. 3, (CH3)ax; 20.4, C1'; 22. 8, (CH3) eq; 24.6, t, J 21.4 Hz, C2'; 24.8, C1''; 26.2, t, J 22.2 Hz, C2''; 36. 4 and 36. 5, C5 ; 55.1 and 55. 2, CZ" ; 61. 1, C6; 74.1, C4 ; 78.0 and 78. 2, C1'''; 125.6, C4''', C6''' and C8'''; 128. 4, C5"'and C7"' ; 135.9 and 136. 0, C3'''. (c) Protection during reaction with organometallic reagents sFs C6F 1 SK 6So4 H '. ", H OH Methyl iodide (0. 04 mL, 0.64 mmol) was added to a suspension of Mg powder (0. 022 g, 0. 93 mmol) in dry Et20 (5 mL) under argon. The mixture was sonicated for 15 min, stirred at reflux for a further 10 min then cooled to room temperature. A solution of 4- [5, 5-bis (3, 3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane]benz aldehyde 33 (0.160 zu 0. 18 mmol) in dry Et2O (10 mL) was added slowly. The mixture was stirred overnight at ambient temperature then quenched carefully by dropwise addition of saturated aq. NH4Cl solution. The aqueous layer was separated and extracted with Et20 (3 x 20 mL). The original organic layer and extracts were combined, dried over anhydrous Na2S04, and evaporated to dryness to give 5, 5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8- tridecafluorooctyl)-2-[4-(1-hydroxyethyl)phenyl]-1,3-dioxane 38 as a colourless oil (0. 160 g, 98%) which solidified after standing overnight at room temperature. The white solid was recrystallized from light petroleum to give a white powder m. p. 65- 66°C (Found: C, 37. 20 ; H, 2. 20. C28H22F26O3 requires: C, 37. 35; H, 2. 46%). vmax 2722, 1670, 1305, 1169, 723. 1H NMR (300 MHz): #1. 44, m, (H1') 2; 1. 47, d, J 6. 4 Hz, (H2iv)3; 1.79, d, J 3.0 Hz, OH; 2.05, m, (H2')2; 2. 09, m, (H1'') 2 ; 2.20, m, (H2") 2 ; 3. 73, d, J 11. 3 Hz, ES and Hax6; 3.96, d, J 11. 3 Hz, Heq4 and Heq6 ; 4. 92, qq, J 6. 4,2. 6 Hz, H1iv; 5.43, s, H2; 7. 39, d, J 8. 3 Hz, H2'"and H6'" ; 7. 45, d, J 8.3 Hz, H3''' and H5'''. 13C NMR. (75. 6 MHz) : #21. 6, C1''; 22.8, C1'; 24.3, C2'; 25.1, C2iv ; 25. 6, C2''; 33. 4, C5; 70. 1, C1iv; 74.2, C4 and C6; 102.0, C2; 125.4, C2"'and C6'''; 129, 7, C3"'and C5'''; 136.7, C4'" ; 146. 9, Cl"'. Mass spectrum : m/z 900 (M+, 1%), 885 (0.4), 855 (1), 417 (4), 205 (4), 149 (20), 107 (30), 81 (47), 69 (100), 55 (50).

(d) Protection during dichromate oxidation

Pyridinium dichromate (0. 550 g, 1. 46 nunol) was added to a solution of 5, 5- bis (3, 3, 4, 4, 5,5, 6, 6, 7,7, 8, $, 8-tridecafluorooctyl)-2- [4-(1-hydroxyethyl)phenyl]-1,3- dioxane 38 (0. 440 g, 0.49 mmol) in CH2Cl2 (25 mL). The mixture was stirred at r. t. for 20 h, then filtered, and the solid residue was washed with Et2O (3 x ZO mL). The titrate and washings were combined and evaporated under vacuum to give a brown solid (0, 424 g) that was passed through a short-pad of silica gel with 15 : 85 Et2O : light petroleum to give 5, 5-bis(3,3,4,4,5,5,6,6, 7, 7,8,8,8-tridecafluoroctyl)-2-(4- ethanoylphenyl)-1,3-dioxane 39 as a white solid (0. 411 g, 94%). (e) Protection during hydrazone formation t13> eF13 ol 8 4 CHsS H ", Ve HN fA, N02 W 40 2 4[5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3- dioxan-2-yl]benzaldehyde 2, 4-dinitrophenylhydrazone 40 (Found : C, 37. 34; H, 1.63 ; N, 5. 32. C28H20F26O3 requires: C, 37. 23; H, 2.09; N, 5. 26%).

Applications in sequential chemical transformations (a) Tagging through aldehyde protection, aldol condensation, dihydropyridine formation

C6FI3 sFl3 4, ir,, NU CH2CH3 CH3 A F 33 e 2<H b CH3e) leq°g e_ CHasH r, xW CH3sw EN>OCH CHO. CH3 CH ? CH3 HNOCi-izCil3 terephthalaldehyde O (5 H3 0 41 42 43 (i) Piperidine (0. 016 g, 0.20 mmol) and glacial acetic acid (0. 012 g, 0. 20 mmol) were added sequentially to a stirred mixture of 4- [5, 5-bis (3, 3, 4, 4, 5, 5, 6, 6, 7,7, 8, 8, 8- tridecafluorootl) 3-dioxane]benzaldehyde 33 (0.150 g, 0.17 mmol) and ethyl acetoacetate (3 mL, 0.15 mmol) at room temperature. After 5 h, the mixture was loaded on to a FRP-SPE cartridge. The cartridge was flushed with 70 : 30 MeOH : H2O then Et2O. The fraction from Et2O was evaporated under vacuum to afford ethyl 2{4-[5,5- bis (3, 3, 8 4, 5, 5, 6,6, 7, 7, @, 8, 8-tridecafluorooctyl)-1,3-dioxan-2-yl]phenylmethylidene}-3- oxopentanoate 41 as a yellow oil (0. 138 g, 82%). The product was a mixture of E and Z isomers.

E isomer (Found: C, 39.85 ; H, 2. 44. C33H26F26O5 requires: C, 39.77; H, 2.63%). vmax 2722, 1719, 1699, 1624, 1260, 1204, 1145, 1065, 1016, 708. 1H NMR (300 MHz, <BR> <BR> <BR> CDCl3): #1.33, t, J 7.2 Hz, COOCH2CH3; 1.44, m, (H1')2; 2.05, m, (H2')2; 2.09, m, (Hl") 2 ; 2.16, m, (H2") 2 ; 2.32, s, COCHg ; 3.73, d, J 11.3 H, Hax4 and Hax6 ; 3. 97, d, J 11.3 Hz, W and H. q6 ; 4. 29, q, J 7. 2 Hz, COOCH2CH3; 5.44, s, H2 ; 7.41, d, J 8.3 ha H2''' and H6''' or H3''' and H5'''; 7.47, d, J 8. 3 Hz, H3''' and H5''' or H2''' and H6'''; 7.66, s, H1iv 13C NMR (75.6 MHz): #14.1, COOCH2CH3 ; 21.5, C1''; 22.7, C1'; 24.3, t, J 22. 5 Ha, C2'; 25. 5, t, J 22.9 Hz, C2''; 31.1, COCH3; 33.5, C5 ; 61. 6, COOCH2CH3; 74. 2, C4 and C6 ; 101.4, C2 ; 126. 6, C2"'and C6''' or C3''' and C5'''; 129.6, C3''' and C5''' or C2''' and C6'''; 133. 7, C1''' or C4''' or C2iv; 134.6, C4''' or C2iv or C1'''; 139.4, C2iv or C1''' or C4'''; 139.6, C1iv; 164.2, COOCH2CH3; 203. 2, COCH3.

Z isomer) 1H NMR (300 MHz, CDCl3): #1.27, t, J 7.2 Hz, COOCH2CH3; 1.44, m, btx 3 ; 2. 05, m, (H2')2; 2.09, m, (H1'') 2; 2.16, m, (H2'')2; 2. 42, s, COCH3; 3.73, d, J 11.3 H, Hax4 and Hax6; 3. 97, d, J 11. 3 Hz, Heq4 and Heq6 ; 4. 31, q, J 7.2 Hz, COOCH2CH3 ; 5.44, s, H2 ; 7. 48, s, H2''', H3'", H5''' and H6'''; 7.55, s, H1iv.13C NMR (75.6 MHz); #13. 7, COOCH2C ; ; 21.5, C1''; 22.7, C1'; 24. 2, t, J 22.6 Hz, C2'; 25.5, t, J 22.2 Hz, C2" ; 26.5, COCH3 ; 33. 5, C5; 61. 7, COOCH2CH3 ; 74.2, C4 and C6; 101.4, C2; 126.6, C2''' and C6"'or C3''' and C5'''; 129. 6, C3''' and C5''' or C2''' and C6'''; 133. 7, Cl"'or C4''' or C2iv; 135. 0, C4'"or or or C1'''; 139. 7, C2iv or C1''' or C4'''; 140.4, C1iv; 167.6, COOCH2CH3; 194.5, COCH3.

(ii) Glacial acetic acid (0. 024 g, 0.40 mmol) was added to a stirred mixture of keto ester 41 (0. 195 g, 0.20 mmol) and methyl 3-aminocrotonate (0. 220, 1. 91 mmol) at room temperature. After 20 h, the mixture was loaded on to a FRP-SPE cartridge. The cartridge was flushed with 70@ 30 MeOSzO then Et2O. The fraction from Et2O afforded 2,6-dimethyl-3,5-bis(ethoxycarbonyl)-4-{4-[5,5-bis (3, 3,4,4,5,5,6,6, 7, 7,8,8,8- tridecafluorooctyl)-1,3-dioxan-2-yl]phenyl}-1,4-dihydropyrid ine 42 as a yellow oil (0.198 g, 92%).

Removal of polyfluorinated acetal tags (i) 2,2-Diphenyl-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl )-1,3-dioxane 10 (0.216 g, 0.37 mmol) and 2 M HCI (1 mL) were refluxed together in acetone (10 mL) for 24 h.

The mixture was diluted with H20 (30 mL) and extracted with Et20 (3 x 20 mL). The extracts were combined, dried over anhydrous Na2SO4 and evaporated to dryness to give a pale solid (0, 213 g) that was chrornatographed on silica gel (12 g). Elution with 5 : 95 Et2O/light petroleum gave benzophenone 43 as a white solid (0.060 g, 99%).

Elution with 100% Et2O afforded 2-(3,3,4,4,5,5,6, 6,7, 7, 8, 8, 8-tridecafluorooetyl)-1, 3- propanediol 1 (0. 172 g, 87%) as a white solid. Compound library synthesis using fluorous tagging strategies F13 its 6F 13 SF, 3 'r''i'i'i' 4 4 . 4 CL. O 00 00 °-' 4 4 4 4 h4 h ! h4 h4 ) 2"T (t j (j /Ct A r 0 0 44 45 46 47

(a) Alkoxybenzaldehyde synthesis General method for phenolic ether formation: A sample of the phenol 12 or 15 (1 mol. equiv.), powdered KOR (20 mol. equiv.) and alkyl halide (20 mol. equiv. ) were warmed together in anhydrous DMF (10 L per mol) in a bath at 70°C. The mixture was heated for 20 h then cooled and 10% volume of H2O was added. The resulting mixture was transferred on to a FRP-SPE cartridge (5 g). The cartridge was eluted sequentially with 70:30 MeOH/H2O (3 x 4 mL), H2O (3 x 4 mL) and Et2O (3 x 4 mL). The Et2O eluants were combined and evaporated under vacuum to dryness. The crude product was examined by NMR spectroscopy and LC-MS analysis to determine the conversion of the reaction and the purity of the crude product.

The general method was used to prepare : (i) (2-(3-Butoxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluo rooctyl)-1,3-dioxane 44 44 2- (3-Hydroxyphenyt)-5- (3, 3, 4, 4, 5, 5, 6, 6, 7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane 12 (0. 107 g, 0. 20 mmol) and n-butyl bromide (0.44 nE, 4. 01 mmol) gave a 73 : 27 mixture of trans-and cis- 2-(3-butoxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluor ooctyl)- 1, 3-dioxane 44 as white needles (0.099 g, 84%, 98. 7% GC-MS purity) m. p. 64-65"C (light petroleum) (Found : C, 45.40 ; H, 4. 00. C22H23F13O3 requires: C, 45. 37; H, 3. 98%) vmax 2721, 2670, 1604, 1591, 1322, 1240, 1209, 1141, 1121, 1073, 781, 707, <BR> <BR> 697 cm-1. 1H NMR (300 MHz); # 0.96, t, J 7.3 Hz, (H4"')3-, 1.44, m, (H1')2; 1.47, m,<BR> <BR> <BR> <BR> (H3"')2; 1.75, m, (H2")', 2.05, m, H5; 2.15, m, (H2')2; 3.58, dd, J 11.7, 11.3 Hz, H@x4 and Hax6; 3.97, t, J 6.6 Hz, (H1")2; 4.26, dd, J 11.7, 4.5 Hz, Heq4 and Heq6; 5.40, s, H2; 6. 87, ddd, J 8. 3, 2.3, 0.8 Hz, H4"; 7. 03, dd, J 7.9, 3.0 Hz, H6"; 7.04, m, H2"'; 7. 26, dd, J 8. 3, 7. 9 Hz, H5". 13C NMR (75. 6 MHz) ; # 13.7, C4""; 18.8, t, J 4.0 Hz, C1'; 19. 1, C3'" ; 28.0, t, J 22.5 Hz, C2'; 31. 2, C2"' ; 33. 5, CS ; 67. 5, C1"'; 71. 7, C4 and C6; 101.4, C2; ni. 6, C2"; 115. 5, C4"; 118. 1, C6" ; 129. 3, C5" ; 139. 3, C1"; 159.2, C3". Mass spectrum; m/z 582 (M+, 10%), 525 (6), 509 (7), 433 (6), 387 (4), 178 (32), 150 (10), 138 (17), 121 (100), 94 (50).

(ii) 2-(3-Isopropoxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecaf luorooctyl)-1,3-diaxane 45

2-(3-Hydroxyphenyl)-5-(3,3,4, 4, 5, 5, 6, 6, 7, 7,8,8,8-tridecafluorooctyl)-1,3-dioxane 12 (0. 015 g, 0. 03 mmol) and 2-bromopropane (0.05 mL, 0.58 mmol) gave 2-(3- isopropoxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro octyl)-1,3-dioxane 45 as a white solid (0. 013 g 88%, 95% GC-MS purity). The solid comprised trans and cis diastereomenc components in a ratio of 76 : 24, evidenced in the 1H NMR spectrum through the appearance of the (H2) signals at D 5. 39 and 5.47, respectively, The solid was recrystallized from light petroleum to give 2-(3-isopropoxyphenyl)-5- (3, 3, 4, 5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane 45 as white flakes m. p. 43- 44°C (Found; C, 44.49; H, 3. 46. C21H21F13O3 requires : C, 44. 38 ; H, 3.72%). 1H NMR (300 1Hz): #1.32, d, J 6.0 Hz, 2xCH3; 1. 43, m, (Hl ; 2. 05, m, H5 ; 2. 15, m, (H2')2; 3. 57, dd, J 11.7, 11.3 Hz, Hax4 and Hax6 ; 4. 26, dd, J 11. 7,4. 5 Hz, Heq4 and Heq6 ; 4. 56, sept, J 6.0 Hz, 3"-OCH(CH#)2; 5.38, s, H2 ; 6.88, ddd, J 8. 3, 2.6, 6 1 Hz, H4' '; 7. 02, m, H6" ; 7. 03, m, H2" 7. 26, d J8. 3, 7. 9 Hz, H5". 13C NMR (75. 6 MHz) : # 18. S, t, J 4.0 Hz, CI' ; 20. 0, 2xCH3 ; 28.0, t, J 22. 5 Hz, C2' ; 33.5, C5; 69. 8, 3"'-OCH (CH3) 2 ; 71. 7, C4 and C6 ; 101.4, C2; 113. 4, C2"; 116. 6, C4" ; 118. 1, C6" ; 129. 3, C5"; 139.4, C1"; 157.9, C3". Mass spectrum : m/z 568 (M+, 1%), 525 (3), 509 (1), 433 (1), 387 (1), 138 (6), 122 (100), 94 (30).

(iii) 2-(3-Allyloxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecaflu orooctyl)-1,3-dioxane 46 46 2-(3-Hydroxyphenyl)-5-(3, 3,4, 4,5, 5, 6, 6, 7,7, 8, 8, 8-tridecafluorooctyl)-1, 3-dioxane 12 (0. 108 g, 0.21 mmol) and allyl bromide (0.35 mL, 4. 05 mmol) gave 2- (3- allyloxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooc tyl)-1,3-dioxane 46 @ 095 g, 821/a, 95% GC-MS purity m.p. 69.5-70°C (Found: C, 44.23; H, 3.31. C21H19F13O3 requires : C, 44.54 ; R 3. 38%). 1H NMR (300 MHz): #1.44, m, (H1')2; 2.10, m, (H2')2; 2. 16, m, H5 ; 3.58, dd, J 11. 7, 11.3 Hz, Hax4 and Hax6; 4. 25, dd, J 11.7, 4.5 Hz, Heq4 and Heq6 ; 4. 54, dt, J 5. 3,1. 5 Hz, (H1"')2; 5.27, ddt, J 10. 6, 1. 5, 1.5 Hz) Hz3"' ; 5. 40, s, H2; 5. 41, ddt, J 17. 3,1. 5, 1. 5 Hz, H@3"'; 6. 05, ddt, J 17. 3,10. 6, 5.3 Hz, H2"'; 6.90, ddd,

J 8. 3,2. 6, 1.1 Hz, H4"; 7. 05, m, H6" ; 7.06, m, H2" ; 7. 26, dd, J 8.3, 7.9 Hz, H5"_13C NMR (75. 6 MHz) : # 18. 0, t, J 4. 0 Hz, C1'; 28.1, t, J 22.5 Hz, C2'; 33. 5, C5 ; 68. 7, C1"'; 71. 7, C4 and C6; 101.3, C2; 112. 0, C2" ; 115.7, C4"; 117. 4, C3"'; 118 5, C6"; 129. 3, C5" ; 133, 2, C2"'; 139.4, C1"; 158. 6, C3". Mass spectrum; m/z 566 (M+, 1%0, 550 (1), 509 (0.5), 433 (1), 387 (1), 161 (31), 133 (27), 121 (45), 105 (25), 65 (39), 55 (53), 41 (100).

(iv) 2-(3-Benzyloxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafl uorooctyl)-1,3-dioxane 47 47 2- (3-Hydroxyphenyl)-5-(3, 3,4, 4, 5, 5, 6, 6, 7,7, 8, 8,8-tridecafluorooctyl)-1,3-dioxane 12 ( 0.251 g, 0. 48 mmol) and benzyl bromide (1. 0 mL, 8. 41 mmol) gave Zu benzyloxyphenyl)-5-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoroo ctyl)-1,3-dioxane 47 as a white solid (0 015 g, 88%, 96% GC-MS purity). The solid comprised trans and cis diastereomeric components in a ratio of 65 ; 35, evidenced in the'H NMR spectrum through the appearance of the (H2) signals at D 5. 41 and 5. 50, respectively. The solid was recrystallized from light petroleum to give 2-(3-benzyloxyphenyl)-5- (3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane 47 as white flakes m. p. 105- 106°C (Found : C, 48. 63 ; R 3.06. C25H21F13O3 requires: C, 48.71 ; H, 3. 43%). 1H NMR (300 MHz): #1.43, m, (H1')2; 2.18, m, H5 ; 2. 08, m, (H2')2 ; 3. 58, dd, J 11.7, 11.3 Hz, Bol4 and Ha@6 ; 4. 26, dd, J 11. 7, 4.5 Hz, Heq4 and Heq6; 5. 07, s, OCH2Ph; 5. 41, s, H2; 6. 95, ddd, J 8. 3, 2. 6, 0. 8 Hz, H4"; 7. 07, d, J 7.5 Hz, H6"; 7.14, m, H2"; 7. 28, dd, J 8. 3, 7.9 Hz, H5". 7.29-7. 45, m, H2"', H3"', H4"', H5"', H6"'. 13C NMR (75.6 MHz): # 18. 8, t J 3.6 Hz, C1'; 28.1, t, J 22.9 Hz, C2'; 33. 5, C5; 69.9, OCH2Ph ; 71.7, C4 and C6; 101. 3, C2 ; 112. 2, C2"; 115.7, C4" ; 118. 6, C6" ; 127.4, C2"' and C6'" ; 127. 8, C3"'and C5"'; 128, 4, C4"'; 129.3, C5" ; 136. 9, C1"'; 139.5, C1"; 158. 8, C3". Mass spectrum : m/z 616 (M+, 4%), 525 (2), 433 (1), 120 (10), 91 (100), 73 (5), 65 (14), 55 (15).

(v) 2-(3-Butyloxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tride cafluorooctyl)-1,3- dioxane 48

48 2- 3-Hydroxyphenyl)-5, 5-bis (3, 3, 4, 4, 5,5, 6, 6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxane 15 (0. 060 g, 0. 07 mmol) and n-butyl bromide (0. 13 mL, 1.25 mmol) gave 2-(3- butoxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluor ooctyl)-1,3-dioxane 48 as a colourless oil b. p. 225°C/1. 0 mnil-t (0.059 g, 92%, 97% GC-MS purity) (Found : C, 38.42; H, 2.50. C30H26F26O3 requires: C, 38.81 ; H, 2.82%).

(vi) 2-(3-Isopropoxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tri decafluorooctyl)-1,3- dioxane 49 2- (3-Hydroxyphenyl)-S, 5-bis (3, 3, 4, 4, 5, 5, 6, 6, 7, 7,8,8,8-tridecafluorooctyl)-1,3-dioxane 15 (0. 100 g, 0. 12 mmol) and 2-bromopropane (0. 22 mL, 2.29 mmol) gave an off-white solid (0. 104 g, 87% conversion, 83% GC-MS purity) which by GC-MS comprised 87% ether 49 and 13% unreacted phenol 15. The crude product was passed through a short pad of silica gel with 5@95 Et2O/light petroleum to give a white solid that was recrystallized from light petroleum to give 2-(3-isopropoxyphenyl)-5,5- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxan e 49 as white needles (0. 082 dz 78%) m. p. 49-50°C (Found : C, 38.17 ; H, 2, 45. C29H24F26O3 requires : C, 38. 09 ; H, 2. 65%). 1H NMR (300 MHz): #1.32, d, J 6. 0 Hz, 2xCH) ; 1.45, m, (Hl') 2 ; 2. 00, (H2')2; 2. 08, m, (H1")2; 2.24, m, (H2") 2; 3.72, d, J 11,7 Hz, Hax4 and Hax6; 3.95, d, J 11.7 Hz, Heq4 and Heq6 ; 4. 56, sept, J 6.0 Hz, 3"'-OCH(CH3)2 ; 5. 39, s, H2 ; 6. 88, ddd, J

8. 3, 2. 3,0. 8 Hz, H4"'; 7.00, m, H2"' and H6"'; 7.27, dd, J 8.3, 7.9 Hz, H5"'. 13C NMR (75. 6 MHz): #21. 7, C1"; 21.9, 2xCH3; 22.8, C1'; 24.3, t, J 22.9 Hz, C2'; 25.6, t, J 22.5 Hz, C2"; 33.4, C5; 69.8, 3"'-OCH(CH3)2; 74.1, C4 and C6; 102.1, C2 ; 113. 3, C2"'; 116. 7, C4"'; 118. 1, C6'" ; 129. 5, Cl"'; 138. 8, C1"'; 157.9, C3'". Mass spectrum: m/z 915 (M+1, 1%), 871 (1), 855 (1), 779 (1), 401 (3), 165 (26), 121 (100), 94 (43), 77 (23), 65 (28). NMR confirmed by COSY and HMQC.

(vii) 2-(3-Allyloxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6, 7, 7, $, 8, 8-tridecafluorooctyl)-1,3- ojceSO dioxane 50 } 6F13> 1'I", o çJ 1" 4 '-y 01, ' (,.",. 2" so 1W Q 2-(3-Hydroxyphenyl)-5} 5-tis (3,3, 4,4, 5, 5,6,6, 7,7, 8,8,8-tridecafluorooctyl)-1,3-dioxane 15 (0. 026 $, 0.03 mmol) and allyl bromide (0. 04 mL, 0. 47 mmol) gave 2-(3- allyloxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecaflu orooctyl)-1,3-dioxane 50 as a colourless oil (0. 026 g, 96%, 98% GC-MS purity) b.p. 250°C/1.0 mmHg (Found: C, 37.99; H, 2.13. C29H22F26O3 requires C, 38. 17; H, 2.43%). 1H NMR (300 MHz, CoCO : 6 1. 45, m, (H1')2; 1.98, m, (H2')2; 2.07, m, (H1'')2 ; 2.20, m, (H2'')2 ; 3. 72, d, J 11.7 Hz, H and Hax6; 3.96, d, J 11.7 Hz, Heq4 and Heq6 ; 4.54, dt, J 5. 3, 1.5 Hz, (H1iv)2; 5.27, ddt, J 10.6, 1. 5, 1.5 Hz, HZ3iv; 5.41, s, H2 ; 5. 41, ddt, J 17.3, 1. 5,1. 5 Hz, HE3iv; 6.05, ddt, J 17.3, 10.6, 5.3 Hz, H2iv; 6.93, ddd, J 8. 3, 2. 6,0. 8 Hz, H4iv ; 7.03, m, H2''' and H6'''; 7. 29, dd, J 8. 3,7. 9 Hz, H5'''.

(viii) 2-(3-Benzyloxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-trid ecafluorooctyl)-1,3- dioxane 51

2- (3-Hydroxyphenyl)-5, 5-bis (3,3, 4,4, 5,5, 6, 6, 7, 7,8,8,8-tridecafluorooctyl)-1,3-dioxane 15 (0. 031 g, 0.04 mmol) and benzyl bromide (0.1 mL, 0. 82 mmol) gave 2- (3- benzyloxyphenyl)-5,5-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafl uorooctyl)-1,3-dioxane 51 (0.034 g, 99%, 98% GC-MS purity) m.p. 82-82.5°C (Found: C, 41. 16; H, 2.46.

C33H24F26O3 requires: C, 41. 18 ; H, 2.51%). 1H NMR (300 MHz): #1. 45, m, (Hl') 2 ; 2. 00, M, (H2')2; 2.09, m, (H1")2; 2.22, M, (H2")2; 3.73, d, J 11. 3 Hz, H,,, and Hax6; 3.96, d, T 11.3 Hz, Heq4 and Heq6; 5.07, s, 3"'-OCH2Ph; 5.41, s, H2; 6.98, d, J 7.9 Hz, H4"'; 7.06, d, J 7. 5 Hz, H6"'; 7.11, s, H2"' ; 7. 30, m, H5"'; 7.32-7.42, m, H2iv, H3iv, H4iv, H5iv and H6iv;. 13C NMR (75.6 MHz); #21.6, C1"; 22.8, C1'; 24.5, C2'; 25. 6 C2"; 33.4, C5; 69.9, 3"'-OCH2Ph ; 74.1, C4 and C6 ; 102. 0, CZ 2, C2"'; 115. 8, C4"', 118 C6"' ; 127.4, C2iv and C6iv; 127.9, C4iv; 128.5, C3iv and C5iv; 129.5, C5"'; 136. 7, C ; 138.9, C1"'; 158.8, C3"'. Mass spectrum; m/z 963 (M+1, 1%), 872 (1), 779 (1), 401 (32), 373 (11), 327 (9), 213 (78), 197 (25), 155 (17), 135 (28), 122 (100).

Polyfluorinated reagents for tagging through acetalation of alcohols, 1, 2-diols, 1, 3-diols and 1, 4-diols (a) Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) ketone 52 white needles m. p. 62- 63°C dit. m. o. 62-63°C) (b) Synthesis of 1, 1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,1-dime thoxy- methane 53 CHsQPCHa C613 6F13 10

Bis (3, 3, 4, 4, 5, 5, 6, 6, 7,7, 8, 8, 8-tridecafluorooctyl) ketone 52 (2. 96 g, 4. 11 mmol) was dissolved in warm anhydrous MeOH (178 mL) under argon. Trimethyl orthoformate (2-61 g, 24.67 mmol) and 18M sulfuric acid (18 drops) were added and the mixture heated under gentle reflux for 48 h. The mixture was cooled and concentrated under reduced pressure, and then diluted with ethyl acetate (100 mL) and water (50 mL). The organic layer was separated and the aqueous layer was extracted with ethyl acetate (2 x 50 mL). The combined organic extracts were washed with 5% aq. sodium bicarbonate (50 mL) and brine (50 mL), and the solution dried (Na2SO4) and evaporated to give 1, 1-bis(3,3,4,4,5,5,6,6, 7,7, 8, 8, 8-tridecafluorooctyl)-1,1-dimethoxymethane 53 as a colourless oil (3. 01 g, 95%) (Found: C, 29.74 ; H, 1.89. C19H14F26O2 requires C, 29. 70 ; e H, 1. 84%). 1H NMR (CDcl3, 300 MHz): # 1.85-2.00, 4H,m, RFCH2,CH2 ; 2. 00-2. 20, 4H, m, RFCH2CH2; 3.19, 6H, s, 2 x OCH3. 13C NMR (CDCl3, 75.6 MHz): # 23. 2, RFCH2, CH2 ; 25. 8, t, J 22.5 Hz, RpCHiCH ; 47. 9, 2 x OCH3; 101. 0, (RFCH2CH2)2C(OCH3)2. EI-MS : mlz 768 (@, 61%), 421 (100), 375 (12), 169 (10), 131 (15), 119 (27), 101 (48), 69 (88).

(c) Synthesis of 2,2-bis(3,3,4,4,5,5,6,6,7,7,8, 8, 8-tridecafluorooctyl)ethanal 54 Pyridinium dichromate (0. 786 g, 2.09 mmol) was added to a solution of alcohol 49 (1. 384 g, 1. 87 mmol) in CHzCl2 (30 mL). The mixture was stirred at r. t. for 20 h, then filtered, and the solid residue was washed with Et20 (3 x 20 mL). The filtrate and washings were combined and evaporated under vacuum to give a brown solid (1. 281 g) that was chromatographed on silica gel (30 g). Elution with 4 96 Etz ht petroleum gave initially bis (3, 3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) ketone 52 as a white solid (0. 361 g, 27°/». Further elution with the same solvent gave a second product that was recrystallized from light petroleum to give 2, 2- bis(3,3,4,4,5,5,6,6, 7, 7,8,8,8-tridecafluorooctyl)ethanal 54 as a white powder (0. 520 g, 38oxo) m. p. 48-49°C (Found : C, 29, 25 ; H, 1, 33. C18H10F26O requires: C, 29.37; H, 1.37%). 1H NMR (300 MHz): #1.81, m, Ha1' and H1a"; 2.05, m, Hb1' and Hb1"; 2. 15, m, (H2) 2 and (H2")2; 2. 49, m, H2; 9.67, s, H1. 13C NMR (75.6 MHz): # 19.1. C1' and C1"; 28.1, t, J 22.5 Hz, C2' and C2"; 49.4, C2 ; 201.6, C1. Mass spectrum: m/z 737 (M+, 2%), 736 (M+, trace), 717 (6), 687 (6), 667 (7), 467 (15), 390 (100), 373 (18), 327 (23), 169 (13), 119 (35) 77 (83), 57 (92).

Applications of acetalation of diols using polyfluorinated reagents 53 and 54 (a) 1, 3-Dioxane forrxation (b) Selective formation of acetals Acetal protection of diols using polyfluorinated reagents 53 and 54

(a) 2-[1, 5-Bis (3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8-tridecafluorooctyl)pent-3-yl]-5,5-dimethyl-1,3- dioxane 55 2, 2-Bis (3, 3, 4,4, 5, 5, 6, 6, 7,7, 8, 8, 8-tridecafluorooctyl)ethanal 54 (0. 175 g, 0. 24 mmol) and 2, 2-dimethyl-1, 3-propanediol (0 029 g, 0. 27 mmol) were treated by Method 3 with Amberlyst 15 (0. 030 g) as catalyst to give a colourless oil (0. 189 g) which was distilled to give 2, 2-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)methyl-5, 5-dimethyl-1, 3- dioxane 55 as a colourless oil (0.179 g, 92%) b. p. 125°C (oven)/0.2 mmHg (Found; C, 33. 47 ; H, 2. 24. C24H22F26O2 requires: C, 33.59; H, 2.45%). 1H NMR (300 MHz): 00-72, s, (CH3)ax; 1.16, s, (CH3)eq; 1. 65, m, Ha1' and Ha1" ; 1. 72, m, H1"'; 1.85, m, Hb1' and Hb1"; 2. 20, m, (H2')2 and (H2")Z; 3.39, d, J 10.9 Hz, Hax4 and Hax6; 3.62, d, J 10. 9 Hz, Heq4 and Heq6 ; 4. 38, d, J 3.4 Hz, H2. 13C NMR (75.6 MHz, CDCl3): # 19. 7, t J 4. 0 Hz, C1' and C1"; 21.6, (CH3)ax; 22. 7, (CH3)eq ; 28. 7, t, J 21.8 Hz, C2' and C2"; 30. 0, CS, 40. 9, Cl"' ; 77. 2, C4 and C6 ; 103.1, C2. Mass spectrum : m/z 822 (M+, absent), 375 (6%), 327 (3), 119 (5), 115 (100), 87 (23), 77 (11), 69 (78), 56 (79).

(b) 2,2-Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-di oxane 56 1,1-Bis(3,3, 4,4, 5, 5, 6, 6, 7, 7, 8, 8, 8-tridecafluorooctyl)-1,1-dimethoxy-methane 53 (100 mg, 0. 13 mmol) was dissolved in toluene (5-mL). Propane-1, 3-diol (20 mg, 0. 26 mmol) andp-toluenesulfanic acid (10 mg, 0. 525 mmol) were added and the mixture refluxed under a Dean-Stark apparatus for 18 h. The toluene was removed under reduced pressure and the residue taken up in diethyl ether (50 mL) and the solution washed with 0. 5M KOH (25 mL). The organic extract was washed with water (25 mL) and dried (K2CO3). Evaporation of the solvent gave a colourless oil (97 mg), which was flash chromatographed on silica get using a gradient of diethyl ether in light petroleum. 2, 2-

Bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,3-dioxan e 56 was obtained as a colourless oil (86 mg, 85%) (Found; C, 31.14; H, 1.85. C20H14F26O2 requires C, 30. 79; H, 1.81%). 1H NMR (CDCl3, 300 MHz): # 1.64-1.75, 2H, m, -OCH2CH2CH2O-; 1.92- 2. 05, 4H, m, RFCH2, CH2 ; 2. 06-2. 35, 4H, m, RFCH2CH2; 3.89, 4H, t, J 5.3 Hz, - <BR> <BR> OCH2CH2CH2- 13C NMR (CDCl3, 75.5 MHz): # 25.1, -OCH2CH2CH2O-; 25.2, RFCH2,CH2; 29.6, RFCH2CH2; 59.5, -OCH2CH2CH2O-; 97.7, C2. EI-MS: m/z 703 (28), 433 (100), 375 (88), 327 (8), 277 (10), 131 (25), 112 (50) and 69 (70).

(cL2, 2-bis (3,3, 4,4, 5, 5, 6, 6, 7, 7,8,8,8-tridecafluorooctyl)-5-methyl-1,3-dioxolane 57 l, I-Bis (3, 3, 4, 4, 5, 5, 6,6,7,7,8,8,8-tridecafluorooctyl)-1,1-dimethoxymethane 53 (100 mg, 0. 13 mmol) was dissolved in benzene (5 mL) and to this propylene glycol (20 mg, 0. 26 mmol) and p-toluenesulfonic acid (10 mg, 0.052 mmole) were added and the mixture refluxed under a Dean-Stark apparatus for 48 h. The solvent was removed under reduced pressure, and the residue taken up in diethyl ether (100 mL). The solution was washed with 0.5 M KOH (50 mL) and then H20 (50 mL), dried (Na2S04), and evaporated to give 2,2-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)- 5-methyl- 1, 3-dioxolane 57 as a colourless oil (103 mg, 98%) (Found : C, 30. 83; H, 1.88.

C20H14F26O2 requires C, 30. 79; R 1. 81%). 1H NMR (CDCl3, 300 MHz) : 8 1. 3O, 3R d Y6. 0 Hz, 4-CH3 ; 1. 80-2. 00, 4H m, RFC,-H2, CH2 ; 2. 10-2. 30, 41-L m, RFCH2CH2; 3.42, 1H, tn I 7. 9 Hz, Ha5; 4.12, 1H, t, J 6.03 Hz, Hb5; 4.20-4.30,1H, m, H4. 13C NMR (CDC13, 75. 6 MHz): # 18.1, 4-CH3 ; 25. 5, RFCH2,CH2 ; 28.1, RFCH2CH2 ; 71. 5, C5 ; 72.9, C4; 109.0, C2. EI-MS: m/z 433 (100%), 417 (25), 375 (95), 327 (8), 277 (8), 169 (10), 131 (18), 119 (20), 113 (32), 77 (35), 69 (55).

(-)-trans-4,5-bis(ethoxycarbonyl)-2, 2-bis (3,3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 8- tridecafluorooctyl)-1, 3-dioxolane 58 A solution of (-)-diethyl tartrate (53. 6 mg, 0.26 mmol), p-toluenesulfonic acid (5 mg, 0.026 rnmol) and 1,1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,1- dimethoxymethane 53 (437 mg, 0. 56 mmol) in toluene (15 mL) was refluxed under a Dean-Stark apparatus for 20 hours. The solution was cooled and diluted with diethyl ether (50 mi) and 0.5 M aq. KOH (25 mL) were added. The organic layer was separated and the aqueous layer extracted with diethyl ether (50 mL). The combined organic extracts were washed with water (50 mL) and dried (Na2SO4). Removal of the solvent gave a colourless oil (300 mg) that was subjected to repeated flash chromatography using an increasing gradient of diethyl ether in light petroleum. The fraction eluted with 20 : 80 diethyl ether/light petroleum gave (-)-trans-4, 5- bis (ethoxycarbonyl)-2, 2-bis (3, 3, 4,4, 5, 5, 6, 6, 7,7, 8,8,8-tridecafluorooctyl)-1,3-dioxolane 58 as a white solid (165 mg, 69 %) m. p. 25-27'C (Found : C, 33. 10; H, 2.27.

C25H20F26O6 requires C, 32.98; H, 2.21%). 1H NMR (CDCl3, 300 MHz): # 1.31 (6H, t, J 7.17 Hz, 2 x OCH2CH3), 1. 95-2. 10 (4H, m, RFCH2,CH2), 2. 15-2. 40 (4H, m, RFCH2CH2), 4. 20-4. 40 (4H, dq, J 7.14, 2. 64 Hz,-2 x OCH2CH3-), 4. 73 (2H, s, X Hs).

1#C NMR (CDCl3, 75.6 MHz): # 13.8, 2 x OCH2CH3 ; 25. 1, RFCH2, CH2; 28.0, RFCH2CH2 ; 62.2, 2 x OCH2CH3 ; 78. 0, C4 and C5; 114. 0, C2; 168.6, CO2CH2CH3 EI- MS; m/z 910 (M+, absent), 563 (85%), 417 (25), 375 (52), 243 (12), 189 (15), 161 (22), 115 (100), 87 (58).

(axis (3,3, 4,4, 5, 5, 6, 6, 7, 7,8,8,8-tridecafluorooctyl)-6-methyl-1,3-dioxane 58 1, 1-Bis (3, 3, 4,4, 5, 5, 6, 6, 7, 7, 8, 8, 8-tridecafluorooctyl)-1,1-dimethoxymethane 53 (200 mg, 0. 26 mmol), 1,3-butanediol (46 mg, 0. 52 mmol) and ptoluenesulfonic acid (10 mg, 0. 05 mmol) were heated together at reflux in toluene (5 mL) under a Dean-Stark apparatus for 20 h-The reaction mixture was concentrated under reduced pressure, diluted with Et2Q (50 mL3, and the solution washed with 0. 5M KOH (25 mL) and Hz0 (25 mL), and dried (Na2SO4). Evaporation of solvent and flash chromatography of the residue using a gradient of Etz4 in light petroleum gave 2, 2- bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-6-methyl-1 ,3-dioxane 58 as a colourless oil (85 mg, 41%) (Found: C, 31. 66; H, 2. 00. C21H16F26O2 requires : C, 31. 75; H, 2. 03%). 1H NMR (300 MHZ, CDCl3); # 1. 16, 3H, d, J6. 0 Hx, 6-CH3 ; 1. 50, 2R m, H5 ; 1. 80, 2H, m, RFCH2CH2; 2 10, 2H, m, RFCH2CH2; 2.30, 2H, m, RFCH2CH2; 3.90, 2H, <BR> <BR> m, H4; 3.95, 1H, m, H6. 13C NMR (CDCl3, 75.6 MHz): # 21.6, RFCH2CH2; 21.8, 6- CH3; 24.3, t, J 21.8 Hz, RFCH2CH2; 26.0, t, J 22.6 Hz, RFCH2CH2; 29.5, RFCH2CH2; 32. 2, C5; 59.6, C4 ; 65. 0, C6 ; 98. 1, C2. EI-MS: m/z (495, 12%), 447 (10), 401 (15), 375 (14), 105 (100).

Later fractions yielded bis (3, 3, 4, 4, 5, 5, 6, 6,7, 7,8,8,8-tridecafluorooctyl) ketone 52 (85 mg, 45 %) as a white solid.

Competitive reactions in the polyfluorinated acetal protecuon of alcohols (a) Reaction of 1, 2,4-butanetriol with 1,1-bis (3, 3, 4, 4, 5, 5, 6p6, 7, 7, 8, 8,8- tridecafluorooctyl)-1,1-dimethoxymethane 53 A solution ofp-toluenesulfonic acid (10 mg, 0. 05 mmol), 1, 2, 4-butanetriol (112 mg, I mmol) and dimethyl acetal 53 (400 mg, 0. 5 mmol) in toluene (10 mL) was heated under reflux in a Dean-Stark apparatus for 20 h. The solution was diluted with Et20 (50 m and the solution washed with 0.5 M aq. KOH (25 mL) and then H2O (25 mL).

Removal of the solvent under reduced pressure gave a colourless oil (384 mg) that was flash chromatographed using a gradient of Et20 and light petroleum, to yield in order, the fluorous ketone 52 (90 mg, 23%), 2,2-bis(3',3',4',4',5',5',6',6',7',7',8',8',8'- tridecafluorooctyl)-4-hydroxyethyl)-1,3-dixoane 60 as a colourless oil (144 mg, 34%) (Found : C, 31. 29; H, 1. 73. C21H16F26O3 requires C, 31. 13; H, 1.99 %). 1H NMR (300 Zu CDCIs) # : 1. 43, IR d, J 2. 4 Hz, Heq5; 1. 65, 1H, m, Hax5; 1.80, 2ici, m, RFCH2CH2; 2.10, 2H, m, RFCH2CH2; 2. 20, 2H, m, RFCH2CH2; 2.30, 2H, m, RFCH2CH2; 3.60, 2H, m, CH2OH; 3.95, 2H, m, H@6; 4.00, 1H, m, Hb6. 13C NMR (75. 5 MH2, Cd13) : D 21. 6, RFCH2CH2 ; 24. 3, RICHS ; 25, 9, RFCH2CH2, C5 ; 29. 4, RFCH2CH2 ; 59.1, C6; 65.8, C1'; 69.7, C4; 98. 4, C2. EI-MS: m/z 810 (M+, absent), 779 (3%), 703 (2), 463 (15), 375 (12), 169 (5), 131 (10), 89 (30), 71 (100), 57 (40). R 3416 (br O'H), 2962 (C-H), 2879 (C-H), 1455 (C-O), 1315 (C-O), 1233 (C-O), 1199, 1121, 1077, 955, 914 846, 812 and 702 cm'' ; and 2, 2-bis (3',3',4',4',5',5',6',6',7',7',8',8',8'- tridecafluorooctyl)-4-(2"-hydroxyethyl)-1,3-dioxolane 61 as a colourless oil (183 mg, 43%) (Found ; C, 30. 89 ; H, 1.67. C21H16F26O3 requires C, 31.13, H, 1.99%). 1H NMR (300 MHb, CDCl3); # 1.85, 2H, m, H1"; 1. 95, 4H, m, 2 x RFCH2CH2; 2.15, 4H, m, 2 x RFCH2CH2; 3.60, 1H, t, J 8.3 Hz, H5 ; 3. 80, 2H, m, H2"; 4. 20, 1H, m, H5; 4. 30, 1H, m, H4. 13C NMR (75.6 Nffiz, CDCl3): #25.7, m, RFCH2CH2; 28.0, RFCH2CH2; 35.7, C1"; 59. 8, C2"; 70.4, C5; 75.3, C4; 109. 0, C2. IR 3390 (O-H), 2969, 2885, 1455, 1324, 1251, 1040 cm-1, EI-MS; m/z 810 (M+, absent), 463 (25%), 417 0, 375 (20), 263 (3), 131 (15), 89 (4), 71 (100).

(b) Treatment of erythritol with 1,1-bis(3, 3,4, 4, 5, 5, 6, 6, 7, 7,8,8,8-tridecafluorooctyl)-1,1- dimethoxymethane 53 Dimethyl acetal 53 (100 mg, 0. 13 mmol), erythritol (meso-1,2, 3, 4-butanediol) (32 mg, 0. 26 mmol) andp-toluenesulfonic acid (2. 5 mg, 0.013 mmol) in toluene (10 mL) were heated together at reflux under a Dean-Stark apparatus for 20 h. The solution was concentrated under reduced pressure, the residue taken up in Et2O (50 mL), and the solution washed with 0. 5 M aq. KOH (25 mL) and H2O (25 mL), and then dried <BR> <BR> <BR> (NaZSO4). Removal of solvent gave a colourless oil, which was repeatedly flash

chromatographed. The fraction eluted with 10 : 90 to 30 ; 70 Et2O : light petroleum initially gave a mixture of products. More careful chromatography gave,. in order of elution, fluorous ketone 52 (25 mg), a 37 : 63 mixture of fluorous ketone 52 and 1, 4- bis (perfluorohexyl) butane, and cis-2, 2-bis(3',3',4',4',5',5',6',6',7',7',8',8',8'- <BR> <BR> tridecafluoroctyl). @furo[3,4-d]-1,3-dioxolane 63 as a colourless oil (6 mg, 60%) (Found : C; H, C21H16F26O3 requires C, ; H, %). #max 1319, 1240, 1205, 1145, 1068, 1031 cm-1.

1H NMR (300 MHz, CDCl3): # 1. 85, 2H, m, RFCH2CH2; 2.00, 2H, m, RFCH2CH2; 2.15, 2H, m, RFCH2CH2; 2.35, 2H, m, RFCH2CH2; 3. 40, zip d, J 10.5 Hz, CHaHb ; 4. 05, 2H, d, J 11.6 Hz, CHaHb ; 4. 79, 2H, s, 2 x CH. 13 C NMR (75.6 MHz, CDCl3) : 0 24. 5, t, @ J 21.1 Hza, RFCH2CH2; 26.2, t, J 22. 6 Hz, RFCH2CH2; 26. 8, RFCH2CH2; 28.1, RFCH2CH2 ; 73.5, CH2O; 81.3, CH; 112.2, C2. EI-MS; m/z 807 (M-1, 1%), 461 (32), 375 (5), 149 (5), 87 (10), 69 (100).

The fraction eluted with 80 : 20 EtaO0Light petroleum, upon further chromatography gave 2, 2-bis(3',3',4',4',5',5',6',6',7',7',8',8',8'-tridecafluoroct yl-4S*-(1R*,2-dihyroxyethyl)-1,3- dioxolane 62 as a white solid (39 mg, 36 %) m. p. 58-60°C (Found: C, 30. 63 ; R 2. 06.

C2iHisF2604 requires C, 30. 52; H, 1. 95%). #max 3400, 1238, 1200 cm-1. 1H NMR (300 MHz, CDCl3) : # 1. 79, J4 t, J 4.9 Hz, OH; 1.95, 4H, m, 2x RFCH2CH2; 2. 16, 4H, m, Z x RFCH2CH2 ; 2.33, 1H, d, J 4.9 Hz, OH; 3.64, 1H, m, H5; 3.76, 1H, m, H4; 3.80, 1H, m, H5; 3.96, 1H, t, J 6.4 Hz, CH2OH; 4. 10, lit q, J 6.4 Hz, CHOH; 4.15, 1H. t, J 6. 4 zu CH2OH. 13C NMR (75. 6 Mein, CDCl3) : CI 25.7, t, J 22.5 Hz, RFCH2CH2; 27. 8, d, J 20, 3 Hz, RFCH2CH2; 63. 4, C5 ; 67. 0, CH2OH; 72. 0, C4 ; 77.3. CHO ; 109. 3, C2. EI-MS: m/z 826 (M+, absent), 765 (4%), 479 (15), 375 (20), 105 (12), 87 (73), 69 (100); and meso-4,4'-bi[2,2-bis(3',3',4',4',5',5',6',6',7',7',8',8',8'- tridecafluoroctyl)-1,3-dioxolane 64 as a white solid (23 mg, 11. 5 %) m.p. 63-64°C (Found: C, 29.74: H, 1.63.

C32Fs204 requires, C, 29. 82; H, 1.45). #max 1236, 1192, 1146 cm-1. 1H NMR (300MHz, CDCl3): # 1.93 (8H, m, 4 x RFCH2CH2), 2.15 (8H, m, 4 x RFCH2CH2), 3.83 (2H, m), 4.12 (2H, m), 4. 18 (2H,m) 13C NMR (75. 5 MHz, CDCl3): # 25. 73 (m, RFCH2CH2), 27.42 (m, RFCH2CH2), 67.07 (CH2OH), 76.72 (CHO), 110.04 (C2). El- MS: m/z 1530 (M+, absent), 1184 (7%), 766 (22), 479 (10), 461 (15), 418 (60), 375 (90).

(c) Treatment of threitol with 1,1-bis(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)-1,1- dimethoxymethane 53

Dimethyl acetal 53 (100 mg, 0.13 mmol) and DL-threitol (+/-1, 2, 3, 4-butanediol) (32 mg, 0.26 mmol) were dissolved in toluene (10 mL), p-toluenesulfonic acid (2. 5 mg, 0.003 mmol) was added, and the mixture heated under a Dean-Stark apparatus for 20 h.

The solution was diluted with EtzO (50 mL) and the solution washed with 0. 5 M SOR (25 rnL) and H2O (25 mL), and then dried (Na2SO4). Removal of solvent gave a colourless oil (132 mg) that was flash chromatographed on silica gel, eluting with a gradient of Et2Q and li$ht petroleum to yield, in order : fluorous ketone 52 (31 mg), (+/- )-4,4'-bi[2,2-bis(3',3',4',4',5',5',6',6',7',7',8',8',8'-tri decafluorooctyl)-1,3-dioxolane 67 as a colourless oil (23 mg, 12%) (Found : C, 29. 76 ; H, 1. 44. C38H22F52O4 requires C, 29.82, H, 1. 45%). #max 1241, 1192 1120 cm-1. 1HNMR (300 MHz, CDCl3); # 1.96 (8H, m, 4 x RFCH2CH2), 2.20 (8H, m, 4 x RFCH2CH2), 3.72 (2R m, CH2), 4.13 (4H, m, CH2, 2 x CH)."C NMR (75.5 MHz, CDCl3), 25.43 (m, RFCH2CH2), 27.61 (RFCH2CH2), 66. 25 (CH2), 76. 01 (CH), 110.29 (C2). EI-MS : m/z 1530 (M+, absent), 1184 (5%), 765 (15), 461 (18), 418 (45), 375 (100); trans-4,5-bis(hydroxymethyl)-2,2- bis(3',3',4',4',5',5',6',6',7',7',8',8',8'-tridecafluoroocty l)-1,3-dioxolane 66 (12 mg, 11%) (Found: C, 30. 38; R 1.95 : C21H16F26O4 requires C, 30. 52; H, 1.95%). IR 3376, 1322 <BR> <BR> 1238, 1148, 1030 cm-1. 1H NMR (300 MHz, CDCl3): # 1.97 (6H, m, RFCH2CH2, OH), 2.23 (4H, m, RFCH2CH2), 3.75 (2H, d, J 12 Hz, CH2OH), 3.85 (2H, d, J 12 Hz, CH2OH), 4. 04 zip s H4, H5). 13C NMR (75.6 MHz, CDC 5. 59 (t, J 23. 4 W RFCH2CH2), 28.64 (RFCH2CH2), 61.71 (2 x CHsOH), 78. 76 (C4, C5), 109.26 (C2). EI- MS: m/z 826 (M+, absent), 795 (2 %), 479 (40), 375 (20), 87 (75); and 2,2- bis (3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl-4S*-(1S*,2-dih ydroxyethyl)-1,3- idoxolane 65 (35 mg, 33 %) (Found: C, 30.43; H, 2.03. C21H16F26O4 requires C, 30. 52; H, 1. 95%). #max 3414, 1249 1238, 1192, 1030 cm-1. 1H NMR (300 MHz, CDCl3) : # 2.00, 5H, m, 2 x RFCH2CH2, OH; 2.20, 4H, m, 2 x RFCH2CH2; 2. 40-2. 50, 1H, bs, OH; 3. 70, 3H, m, H4, H5; 3. 90, 1H, t, J 7.5 a CH2OH; 4.10, 1H, m, CH2OH; 4.20, 1H, m, CHOH. 13C NMR (75.6 MHz, CDCl3) : 26.0, RFCH2CH2 ; 28.4, RFCH2CH2 ; 64.4, C5 ; 66.9, C2" ; 71. 9, C4 ; 78.2, C1"; 110. 2, C2. EI-MS: m/z 826 (M+, absent), 795 (1 %), 765 (5), 479 (20), 375 (18), 105 (20), 87 (100).

Reactions of polyfluorinated acetal protected substances (a) Oxidative cleavage of diol 65 A solution of NaIO4 (41 mg 0. 14 mmol) in HO (1 mL) was added to a solution of diol 65 (38 mg, 0. 048 mmol) in 1, 4-dioxane (2 mL) and the mixture was stirred for 3 d. The solution was filtered through Biter aid with the aid of CHCl3 (20 mL). The filtrate was evaporated to dryness under reduced pressure, and the residue extracted with CHC13 (2 x 50 mL). Removal of solvent gave a colourless oil (61 mg), which was flash chromatographed, elutrng with 50: 50 Et2O/light petroleum, to yield zu bis (3, 3, 4, 4,5, 5, 6, 6, 7, 7, 8, 8,8-tridecafluorooctyl)-1,3-dioxolan-4-yl]carboxaldehyde 68 as a colourless oil (22 mg, 40%) (Found : C, 30. 39 ; 1, 1. 31. C20H12F26O3 requires C, 30.24, H, 1. 52%). #max 3453, 1740, 1455, 1321, 1238 cm-1. 1H NMR (300 MHz, CDCl3): # 1. 95, 4R m, 2 x RFCH2CH2; 2. 10, 4H, m, 2 x RFCH2CH2; 4.10, 1H, m, H5 ; 4.25, 1H, t, J 9.0 Hz, H5 ; 4. 49, 1 dt, J 6. 0 X 1. 5 a7 H4; 9.71, 1H, d, J 1.5 Hz, 4-CHO. 13C NMR (75.6 MHz, CDCl3): # 25.7, t, J 22.6 Hz, RFCH2CH2; 27.3, RFCH2CH2; 65.5, C5; 79.8, C4; 111.4, C2; 198.7, CHO. EI-MS : iZ 794 (M+, absent), 765 (10%), 447 (38), 375 (8), 169 (32), 119 (88), 169 (100).

(b) Mild oxidation of 2,2-bis (3, 3, 4, 4, 5, 5, 6, 6,7,7,8,8,8-tridecafluorooctyl-4S*-(1S*,2- dihydroxyethyl)-1, 3-dioxolane 65 using pyridinium dichromate Pyridinium dichromate (81 mg, 0.21 mol) was added portionwise to a solution of 2, 2- bis (3, 3, 4, 4, 5,5, 6, 6, 7, 7, 8,8,8-tridecafluorooctyl-4S*-(1S*,2-dihydroxyethyl)-1,3- dioxolane 65 (35 mg, 0.04 mmol) in dry CHsCIa (2 mL). The mixture was stirred at r. t. for 20 h. The solution was filtered through filter aid and the pad washed several times with CH2Cl2 (50 The The organic titrate was evaporated to dryness under reduced pressure to give a brown oil (33 mg) that was flash chromatography using an Et7, in light petroleum gradient to give 2-[2,2-bis(3',3',4',4',5',5',6',6',7',7',8',8',8'- tridecafluorooctyl)-1,3-dioxolan-4-yl]ethanal 69 as a colourless oil (t 48

(Found: C, 31.08; H, 1.71. C21H14F26O3 requires C, 31. 21; H, 1.75%). #max 2963, 2880, 1730 (C=O), 1455, 1322, 1240, 1196, 1145, 1121, 1088 1025 cm-1. 1H NMR (300 MHz, CDCl3): # 1.90, 4H, m, 2 x RFCH2CH2; 2.20, 4H, m, 2 x RFCH2CH2; 2.65, 1H, dd, J 17. 7,6. 7 Hz, CH2CHO; 3.00, 1H, ddd, J 17.7, 6, 1.1 Hz, CH2CHO; 3.55, 1H, t, J 8. 3 Hz, H5; 4.30, 1H, m, H5 ; 4. 55, 1H, m, H4 ; 9. 79, s, CHO. 13C NMR (75.6 MHz, CDCIs) : # 25.67 (RFCH2CH2), 27.76 (Rr-CH2_CI-12), 47.40 (CH2CHO), 69. 92 (Cs), 71. 29 (C4), 109.24 (C2), 198. 52 (CHO). EI-MS : m/z 808 (M+, absent), 765 (M+-CH2CHO, 1), 461 (M+-CH2CH2C6F13, 2), 417 (5), 375 (8), 87 (15), 69 (100).

Unreacted alcohol 65 (10 mg, 29%) was obtained from 70 : 30 Et20 : light petroleum.

(c) Vigorous oxidation of2, 2-bis (3,3, 4,4, 5, 5,6, 6,7, 7, 8, 8, 8-tridecafluorooetyl-4S*- (1S*,2-dihydroxyethyl)-1,3-dioxolane 65 using pyridinium dichromate Pyridinium dichromate (267 rng, 0. 7 mmol) was added slowly to a solution of alcohol 65 (115 mg, 0.14 mmol) in dry CH2Cl2. The mixture was stirred at r. t. for 3 d, then filtered through filter aid with the aid of CH2Cl2 (50 mL). Evaporation of the solvent and flash chrornatography of the residue on silica gel gave aldehyde 69 (17 mg, 17%), followed in the 95:5 Et2O/light petroleum fraction, 2-[2,2- bis(3',3',4',4',5',5',6',6',7',7',8',8',8'-tridecafluoroocty l)-1,3-dioxolan-4-yl]ethanoic acid 70 as a white solid (124 mg, 24%) m.p. 58-60°C (light petroleum) (Found : C, 30. 58; H, 1.44. C21H14F26O4 requires C, 30.60; H, 1.71%). Vx 3400-3000 (0-H), 2960, 2927, 1720 (C=O), 1455, 1322, 1240, 1202, 1145, 1121, 1088, 1024 cm-1.

1H NMR (300MHz, CDCl3): # 1. 90, 4R m, 2 x RFCH2CH2 ; 2. 20, 4H, % 2 x RCHzCHz ; 2.60, 1R, dd, # 17 Hz, 7 Hz, CH2COOH ; 2. 80, 1H, dd, J 17, 7 Hz, CH2COOH; 3. 70, zu t, J 3 Hz, H5; 4.30, 1H, m, H5 ; 4, 50, 1H, m, H4.'3C NMR (75.6 MHz, CDCl3) 25.7, RFCH2CH2; 27.6, RFCH2CH2; 38.0, C2; 69. 6, C5'; 72.4, C4'; 109. 5, C2'; 175.5, C1. EI-MS: m/z 824 (M+, absent), 765 (1%), 477 (12), 417 (6), 375 (5), 131 (6), 119 (10), 103 (12), 85 (100).

(d) Hydnde de reduction of (-)-trans-4,5-bis(ethoxycarbonyl)-2,2- bis (3, 3, 4, 4,5,5,6,6, 7, 7, 8, 8, 8-tridecafluorooctyl)-1, 3-dioxolane (-)-58 Diester (-)58 (60 mg, 0. 06 mol) in dry Et2O (2 mL) was added dropwise to a suspension of LiAJBLt (12. 5 mg, 0. 32 mmol) in dry Et2O (1 mL). The mixture was

stirred at ambient temperature for 20 h, then quenched with 10% aq. KOH, and filtered through filter aid. The titrate was separated and the aqueous layer extracted exhaustively with Et2O (25 mL). The combined organic extracts were dried (Na2SO4), evaporated to dryness, and the resulting colourless oil (3 7 mg) flash cbromatographod, eluting with 75 : 25 Et20 ; light petroleum to yield (-)-trans-4,5-bis(hydroxymethyl)- 2,2-bis (3, 3, 4, 4, 5, 5, 6, 6,7, 7, 8, 8, 8-iridecafluorooctyl)-1, 3-dioxolane (-)-66 as a colourless oil (36 mg, 67 %), which had identical spectroscopic properties to those observed for the racemic sample.

References 1. Pereira, S.M., Savage, G. P., Simpson, G. W., bo. Commun., 1995, 25, 1023- <BR> <BR> <BR> 1026.<BR> <BR> <BR> <BR> <P>2. a. Hovàth, I.T., Rabai, J. Science, 1994, 266, 72-75; b. Horvatb, I. T. , Acç Chem.<BR> <BR> <BR> <BR> <P> Res. 1998, 31, 41-650 ; c. Gladysz, J. A. , Scietice, 1994, 266, 55-56 ; d. Curran, D. P., Angew. Chem., Int.Ed.Engl., 1998, 37, 1174.

3. Curran, D.P., Chemtracts-Organic Chemistry, 1996, 75-87.

4. Studer, A., Hadida, S. , Ferritto, R, Kim, S.-Y., Jeger, P., Wipi. P., Curran, D. P., Science, 1997, 275, 823-826. <BR> <BR> <BR> <P>S. Bhattacharyya, P., Gudmunsen, D., Hope, E. G. , Kemmitt, R. D. W. , Paige, D. R., Stuart, A.M., J. Chem. Soc., Perkin Trans. 1, 1997, 3609-3612 and references therein.

6. a. Currant, DP, Hadida, S. , J. Am. Chem. Soc., 1996, 118, 2531; b. Larhed, M., Hoshmo, M., Hadida, S., Curran, D.P., Hallberg, A., J. Org. Chem., 1997, 62, 5583-5587; c. Curran, D.P., Hadida, S., He, M., J. Org. Chem., 1997, 62, 6714- 6715; d. Curran, D.P., Luo, Z., Degenkolb, P., Bioorg. Med. Chem. Lett., 1998, 8, 2403-2408.

7. Studer, A., Curran, D. P., Tetrahedron, 1997, 53, 6681-6696.

S. Studer, A., Jeger, P. Wipf, P. , Curran, D. P., J. Org. Chem., 1997, 62, 2917-2924.

9. Kainz, S., Koch, D., Baumann, W., Leitner, W., Angew. Chem., Int. Ed. Engl., 1997, 36, 1628.

10. Ogawa, A., CUITS, D.P., J. Org. Chem., 1997, 62, 450-451.

11. FC-72 is a commercial solvent, b.p. 56°C, that is sold by 3M and is a mixture of perfluorohexanes, C6F14.

12. Kainz, S. , Luo, Z., Curran, D. P., Leitner, W., Synthesis, 1998, 1425-1427.

13."Fishing-out", see Walters, M. A., Chemtracts-Organic Chemistry, 1998, 11, 1013- 1024.

14. T. W Greene and P. G. M. Wuts,"Protective Groups in Organic Synthesis", 2nd Ed.

(Wiley : New York 1991).

15. P. JKocienski,"Protecting Groups", (Thieme : Stuttgart 1994 _ 16. Alexakis, A., Mangeney, P., tetrahedron Asymm., 1990, 1, 477-511.

17. Seebach, D. , Ae7gew. Chem., Int. Edn. Engl., 1979, 18, 239-258.

18. Schmeltz, K. C. , Fluorinated alcohols, US Patent 3478116, 1969, 9pp 19. Schmeltz, K. C., Fluorinated polyesters, US Patent 3504016, 1970, Spp 20. Schmeltz, K. C., Fluorinated polyurethanes for oil-and waterproofing textiles, US Patent 3547894,1970, 5pp 21. Schmeltz, K.C., Fluorinated acids and esters, US Patent 3578701, 1971, 9pp (Chem. Abstr., 1971, 72, 33199m) Throughout this specification the word"comprise", or variations such as "comprises"or"compnsing", wxll be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

Moreover, any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed in Australia before the priority date of each claim of this application.

Furthermore, it win be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.