ADDITION OF HYDROFLUORCARBONS TO FLUOROOLEFINS FIELD OF THE INVENTION This invention concerns a process for the antimony pentafluoride catalvzed addition of hydrotluorocarbons across the carbon-carbon double bond of tiuoroolefins.

BACKGROUND Processes for the addition of 1,1, 1-trifluoroethane to fluorinated olefins using antimony pentafluoride as a catalyst have been described (see G. G.

Belen'kii and L. S. German,Soviet Scientific Reviews, Sect. B, pp. 195-6, M. E. Volpin ed., (Harwood Academic Publishers, 1984). Processes for the addition of trifluoromethanes, including CHF3, to certain fluorinated olefins using aluminum chlorofluoride as a catalyst have also been described (see U.S.

Patent Application No. 06/000,720 and International Application No.

PCT/US96/10872). Hydrofluorocarbons can be prepared by both processes.

Hydrofluorocarbon products are useful as refrigerants, fire extinguishants, heat transfer media, propellants, foaming agents, gaseous dielectrics, sterilant carriers, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, displacement drying agents and power cycle working fluids. There is an interest in developing more efficient processes for the manufacture of hydrofluoroalkanes.

SUMMARY OF THE INVENTION A process is provided for forming an adduct of the formula RR1R2CCR1R2F or (FR1R2CCRR2CH2)2 wherein R is selected from the group consisting of CH3, CH2F, C2H4F and F(CF2)nCH2CH2 where n is an integer from 1 to 10, each R1 is independently selected from the group consisting of H, Cl, F and CF3 and each R2 is independently selected from the group consisting of H, F and CF. The process comprises reacting a saturated compound of the formula RF with an~olefin of the formula R R²C=CR R² in the liquid phase in the presence of antimony pentafluoride catalyst; provided that when (FR1R2CCRlR2CH2)2 is formed, the saturated compound is CH3CHF2 or CH2FCH2F and anhydrous HF is present.

DETAILED DESCRIPTION OF THE INVENTION This invention provides a liquid phase process for the addition of (a) saturated compounds of the formula RF, where R is selected from the group consisting of CH3, CH2F, C2H4F and F(CF2)nCH2CH2, where n is an integer from 1 to 10, to (b) olefins of the formula R R²C=CR R² where each R1 is independently selected from the group consisting of H, Cl, F and CF3 and each R2 is independently selected from the group consisting of H, F and CF3; to

tOrm inducts of the formula RR R²CCR R²F or (FR R²CCR R²CH2)2 in the presence of antimony pentafluoride catalyst (provided that when (FRtR2CCRIR2CM,)i is formed. the saturated compound is CH3CHF2 or CH.FCH2F and anhydrous HF is present).

Examples of olefins of the formula R R²C=CR R² which can be used in the process of this invention include CF2=CF2, CF3CF=CF2. CCIF=CF2.

CCIF=CCIF, CHF=CF2, CH2=CF2, CF3CH=CF2, CHF=CFCF3 and CH2=C(CF3)CF3. Some of the olefins are commercially available, the others can be prepared by known methods.

Examples of saturated compounds of the formula RF which can be used in the process of this invention include CH3F, CH2F2 and CH3CHF2.

Solvents or diluents may be employed in the process of the present invention. The solvent or diluent is selected so that it will not be reactive in the process or lead to the deactivation of the antimony fluoride catalyst. Suitable solvents or diluents may be selected from the group consisting of perfluoroalkanes or perfluoroethers (e.g., perfluorocyclobutane); the cyclic dimer of hexafluoropropene (i.e., the isomeric perfluorodimethylcyclobutanes); perfluoroethers or perfluoro tertiary amines. Preferred on the basis of its ready availability to those skilled in the art is the cyclic dimer of hexafluoropropene.

In one embodiment a one to one adduct of the saturated compound and the olefin is formed. It is noted in this regard that the saturated compounds of the formula F(CF2)iiCH2CH2F can themselves be produced as one to one adducts. For example, the addition reaction of CH2FCH2F to CF2=CF2 can be used to produce F(CF2)2CH2CH2F.

In a second embodiment of this invention the addition of the hydrofluorocarbons CH3CHF2 and/or FCH2CH2F to olefins of the formula R1R2C=CR1R2 in the presence of antimony'pentafluoride can be done in the presence of anhydrous HF. The molar ratio of HF:SbF5 is in the range of 10:1 to 40: 1, preferably 20:1. The addition product or adduct is (FR1R2CCR1R2CH2)2. Without wishing to be bound by theory, it is believed that when CH3CHF2 is used it isomerizes to FCH2CH2F before reaction with the olefin.

When the addition product (adduct) contains chlorine, the chlorine can be removed by either reaction with HF in the presence of a fluorination catalyst (e.g., Cr2O3) or by reaction with hydrogen in the presence of a hydrogenation catalyst (e.g., palladium supported on carbon). The adduct is thereby converted from a hydrochlorofluorocarbon to a hydrofluorocarbon.

The temperature employed in the process of the present invention typically ranges from about -10°C to about 100'C. The preferred temperature range is from about 0°C to 80"C.

Reaction time is not critical and typically ranges from about S seconds to about 24 hours. From about I to 16 hours, are usually sufficient.

The pressure employed in the reaction is not critical. The reaction is normally run at pressures in the range of from 0 to 300 psig (101 kPa to 2169 kPa). Autogenous pressures are usually employed; however the pressure should not be allowed to rise above 300 psig when using tetrafluoroethylene because of safety considerations.

Where the reaction conditions are heterogeneous, some degree of agitation is often desirable.

Sinct the catalysts are water sensitive, reagents and equipment should be dried before use.

The proportion of catalyst to the olefin reactant is typically from about 0.01:1 to about Q.5:1; a range of from 0.1:1 to about 0.5:1 is preferred.

The proportion of saturated compound to oleffn is preferably at least about preferably 1:1, when forming RR1R2CCR1R2F and preferably at least about 2:1 when forming (FRlR2CCRlR2CH2)2. Of note are embodiments which use saturated compounds as a solvent such that they are present in substantial excess.

The reaction can be done in batch, semi-batch, semi-continuous or continuous modes in one or more reaction vessels. On a laboratory scale, the reaction can be done in shaker tubes, where all reagents are combined before the reaction vessel is sealed and the reaction begun. It can also be done in autoclaves equipped with an agitator. Product(s) may be isolated by standard chemical engineering techniques, e.g., fractional distillation.

Without further elaboration, it is believed that one skilled in the art can, using the description herein, utilize the present invention to its fullest extent.

The following specific embodiments are, therefore, to be construed as merely illustrative, and do not constrain the remainder of the disclosure in any way whatsoever.

EXAMPLES EXAMPLE 1 CH2F, + CF2=CF2 o CHFCFzCFq Difluoromethane (39.0 g, 0.75 mol), antimony pentafluoride (45 g, 0.2 mol) and tetrafluoroethylene (30.0 g, 0.3 mol) were added to a 250 mL steel autoclave. The reaction mixture was stirred at 50°C for 8 hours, additional

tetrafluoroethylene (30.0 g. 0.3 mol) added, and stirring was maintained at 500.C tor 8 more hours. The gaseous reaction products were condensed in a trap. then distilled to yield CH2FCF2CF3 (75 g 80% yield). b.p. 0-1°C.

19F NMR (6, ppm, relative to CF3CO2H) of CH2FCCF2BCF3A: A 8.5, B 51.5, C 167.6, JFA-C is 9 Hz, JFB-H is 12 HZ. JFC.H is 45 Hz. tH NMR (8, ppm, relative to TMS): 5.26 (CH2).

COMPARATIVE EXAMPLE A CH2F2+CF2=CF2#No Reaction) Difluoromethane (26 g), aluminum chlorofluoride (AlClxFy where x+y=3, 5 g) and tetrafluoroethylene (30 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube. The aluminum chlorofluoride was prepared by the reaction of AlCl3 and CC13F according to the method described in U.S. Pat.

No. 5,162,594, column 4, lines 35-57. The reaction mixture was agitated at 25°C FOR 12 hours. No reaction was detected.

EXAMPLE 2 CH2F2+CF2=CFCF3#CH2FCF(CF3)2 Difluoromethane (39.0 g, 0.75 mol), antimony pentafluoride (45 g, 0.2 mol) and perfluoropropylene (66 g, 0.44 mol) were added to a 250 mL steel autoclave. The reaction mixture was stirred at 800C for 20 hours. The reaction products were condensed in a trap, then distilled to yield CH2FCF(CF3)2 (80 g, 90% yield), b.p. 22-24°C.

19F NMR (6) of CH2FCCFB(CF3A)2: FA 0.5, FB 114, FC 167.5, JFA-FB is 7 Hz, JFA-FC is 9.5 Hz, JFC-FB is 12.5 Hz, JFA-H is 11 Hz. 1H NMR (#): 5.25 (CH2), JFC-H is 45 Hz, JFB-H is 16 Hz.

Mass spectrum (m/z, assignment, %): 201 (M-H)+ 0.03, 183 (M-F)+ 2.04, 163 (C4HF6)+ 1.4, 150 (C3F6)+ 34.4, 133 (C3H2F5)+ 3.4, 131 (C3Fs)+ 6.3, 119(C2F5)+ 4.4, 114 (C3H2F4)+ 229, 113 (C3HF4)+ 27.3, 100 (C2F4)+ 22.6, 69 (CF3)+ 100.

EXAMPLE 3 CH3F+CF2=CF2#CH2CF2CF3 Fluoromethane (35.0 g), antimony pentafluoride (15 g) and tetrafluoroethylene (50 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube. The reaction mixture was agitated at 25°C for 6 hours followed by agitation at 50°C for 10 hours. The reaction products were condensed in a dry- ice trap, then distilled to yield 99% pure CH3CF2CF3 (HFC-245cb, 45 g), b.p.

-13 to -12°C. The yield of HFC-245cb was 67%.

COMPARATIVE EXAMPLE B CHFl + CF,=CF, # PTFE Trifluoromethane (21 g), antimony pentafluoride (7 g) and tetrafluoro- ethylene (30 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube.

The reaction mixture was agitated at 25°C for 12 hours. The only product isolated was polytetrafluoroethylene (PTFE, 15 g).

EXAMPLE 4 CH3F + CF2=CFCF3 # (CF3)2CHF + (CF3)2CFCH3 + (CF3)2CFC(CH3)3 + (CF3)2CFC2H5 Fluoromethane (20 g), antimony pentafluoride (15 g) and hexafluoro- propylene (75 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube.

The reaction mixture was agitated at 50°C for 14 hours. The reaction products were condensed in a dry-ice trap, then distilled to yield a mixture (68 g) containing, based on 1H and 19F NMR,. 66 % (CF3)2CHF, 11% (CF3)2CFCH3, 5% (CF3)2CFC2H5, 9% (CF3)2CFC(CH3)3. The yield of (CF3)2CFCH3 was 4%.

EXAMPLE 5 CH3F + CCIF=CF2#CLCF2CF2CH3 + CF3CF2CH3 + CF3CCIFCH3 Fluoromethane (17 g), antimony pentafluoride (15 g) and chlorotrifluoroethylene (59 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube. The reaction mixture was agitated at 50°C for 12 hours. The reaction products were condensed in a dry-ice trap, then distilled to yield a mixture (12 g) containing, based on 1H and 19F NMR, 87.5% ClCF2CF2CH3, 6.5% CF3CF2CH3, 4% CF3CFClCH3 and 1% unidentified product. The yield of chlorofluoropropanes was 17.4%.

EXAMPLE 6 CH3F + CHF=CF2#CH3CHFCF3 + CH2FCF3 Fluoromethane (10 g), antimony pentafluoride (10 g) and trifluoroethylene (24 g) were added to a 400 mL HastelloyN nickel alloy shaker tube. The reaction mixture was agitated at 25°C for 14 hours. The reaction products were condensed in a dry-ice trap, then distilled to yield a mixture (12 g, b.p. 0 to 20C) containing, based on 1H and 19F NMR, 90% CH3CHFCF3 and 10% CH2FCF3. The yield of CH3CHFCF3 was 38.6%.

EXAMPLE 7 CHoFa + CCIF=CCIF -4 CH2ClCF2CF2Cl Difluoromethane (18 L, 0.7 mol), antimony pentafluoride (22 g, 0.1 mol) and 1 ,2-dichlorodifluoroethylene (26.6 g, 0.2 mol) were added to a 250 mL steel autoclave. The reaction mixture was stirred at room temperature

for 8 hours followed by heating the autoclave in a boiling water bath. The reaction products were condensed in a trap cooled to -780C. Excess difluoromethane was separated by distillation. The residue was washed with water, dried and distilled to give in 32% yield CH2CICFrCFrCI (12 g, b.p.

62°C to 64°C).

19F NMR (6) of CH2ClCF2BCF2ACl: -50 s (2FA): 41.5 t (2FB). 1H NMR (#) 3.8; J[H-FB] is 14 Hz.

Mass spectrum (m/z, assignment, %): 184 (M+, C3H2C12F++. 0.5); 165 (M-F, C3H2Cl2F3+, 0.3); 149 (M-Cl, C3H2ClF4+, 17.7): 99 (C2H2CIF2+, 100); 85 (CClF2+, 33); 64 (C2H2F2+, 12).

EXAMPLE 8 CH3CHF2 + CF2=CF2+CH3CHFCF2CF3 + CH2FCH2CF2CF3 1,1 -Difluoroethane (53 g, 0.8 mol), antimony pentafluoride (44 g, 0.2 mol) and tetrafluoroethylene (8.5 L, 0.3 mol) were added to a 250 mL steel autoclave. The reaction mixture was stirred at 40°C to 500C for 10 hours. The reaction products were bubbled through a gas-washing bottle containing water and condensed in a trap cooled to -78°C. Excess 1,1-difluoroethane was separated by distillation. The residue was washed with water, dried and distilled to yield a mixture in 40% yield (20 g, b.p. 23°C to 27°C) containing CH3CHFCF2CF3 (89%) and CH2FCH2CF2CF3 (11%). l9F NMR (6) of CH3lCHFDCFAFBCF3C: 7.5 (3FA); 55 (FA, FB, AB-system); 120 (FD); JFC-FD is 10 Hz; JFA-FB is 230 Hz; J[FA(FB)-FD] is 16 Hz; J[FA(FB)-H ] is 7 Hz; J[FA(FB)-H²] is 17 Hz; J[FD-H²] is 45 Hz. 1H NMR (#): 1.7 (H ); 5.25 (H2); J[H -H²] is 7 Hz.

19F NMR (6) of CH21FCCH22CF2BCF3A: 11.5 (3FA); 42.5 (2FB); 147.5 (Fc); 55 (FB); J(FB-FC) is 5 Hz; J(FB.Hl) is 18 Hz; J(FC-H²) is 45 Hz; J(FC Hl) is 28 Hz.

EXAMPLE 9 CH3CHF2 + CF22=CF2#(CF3CF2)2(CH2)(CH2)2 + CF3CF=CHCH2CF2CF3 Anhydrous HF (80 mL), 1,1-difluoroethane (11 g, 0.2 mol), antimony pentafluoride (45 g, 0.2 mol) and tetrafluoroethylene (40 g, 0.4 mol) were added to a 250 mL steel autoclave. The reaction mixture was agitated at room temperature for 8 hours followed by heating the autoclave in a boiling water bath. The reaction products were collected in a gas-washing bottle containing water. The organic layer was separated, washed with water, dried and distilled to yield a mixture in 50% yield (27 g, b.p. 46 to 58°C) containing CF3CF2CH2CH2CF2CF3 (70%) and CF3CF=CHCH2CF2CF3 (30%). The

reaction mixture also contained a small amount )t 1-perfluoroethyl-2.2.3- tetratluorocyclobutane.

19F NMR (#) of CF3CF2CH2CH2CF2CF3: 11 (CF3); 44.5 (CF2); JH-F was 16 Hz. H NMR (5): 2.5 m (2CH2).

Mass spectrum (m/z. assignment. %): 247 (M-F. C6H4F9+. 0.1); 227 (C6H3F8+, 9.7); 197 (C5H4F7+, 18.9); 177 (C5H3F6+., 29.6); 157 (C5H2F5+, 6.7); 127 (C4H3F4+, 24.3); 119 (C2F5+, 5.6); 113 (C3HF4+, 31.3); 100 (C2F4+, 3.9); 77 (C3H3F2+, 43.3); 69 (CF3+, 68.4).

19F NMR (6) of CF3ACFB=CH2CH2lCF2CCF3D: -1.2 (3Fa); 10.5 (3FD); 42.5 (2FC); 55 (FB); J(FA-FB) is 10 Hz. 1H NMR (5): 3. 1 (2Ht); 5.8 (1H2); J(H²-FB) is 30 Hz; J(H -H²) is 7.5 Hz; J(H -FC) is 10 Hz. Raman spectrum (v, cm-1): 1728.

MasS spectrum (m/z, assignment, %): 246 (M+, C6H3F9+, 9.6); 227 (C6H3F8+, 8.5); 207 (C6H2F7+, 2.3); 177 (C5H3F6+, 7); 157 (C3H2F5+, 0.7); 127 (C4H3F4+, 66); 119 (C2Fs+, 2.6); 113 (C3HF4+, 20.3); 77 (C3H3F2+, 100); 69 (CF3+, 68.4).

Mass spectrum (m/z, assignment, %): 227 (MF+, C6H3F8+, 0.8); 207 (C6H2F7+, 1.6); 177 (C5H3F6+, 1.8); 157 (C5H2F5+, 1.9); 127 (C4H3F4+, 4.5); 113 (C3HF4+, 9.7); 100 (C2F4+, 13); 77 <BR> <BR> <BR> (C3H3F2+, 12); 69 (CF3+, 10.6); 64 (C2H2F2+, 100).<BR> <P> COMPARATIVE EXAMPLE C (CH3)2CHF + CF2=CF2#Tar Isopropyl fluoride (25 g), antimony pentafluoride (25 g) and tetrafluoro- ethylene (40 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube.

The reaction mixture was agitated at 25°C for 12 hours. Only a tarry product was isolated.

COMPARATIVE EXAMPLE D CF3CH2F + CF2=CF2#PTFE 1,1,1 ,2-Tetrafluoroethane (50 g), antimony pentafluoride (5 g) and tetrafluoroethylene (40 g) were added to a 400 mL HastelloyTM nickel alloy shaker tube. The reaction mixture was agitated at 50°C for 12 hours. The product isolated was polytetrafluoroethylene (PTFE, 10 g) along with recovered CF3CH2F (46 g).

COMPARATIVE EXAMPLE E HCF2CF2CH2F + CF2=CF2 -4 PTFE 1,1,2,2,3-Pentafluoropropane (55 g), antimony pentafluoride (20 g) and tetrafluoroethylene (30 g) were added to a 400 mL HastelloyrU nickel alloy

shaker tube. The reaction mixture was agitated at 50°C for 12 hours. The product isolated was polytetrafluoroethylene (PTFE, 20 g) along with recovered HCF2CF2CH2F (32 g).

COMPARATIVE EXAMPLE F CH2F2 + CF2=CF2#CH2FCF2CF3 + CF2=CF2#PTFE Difluoromethane (55 g), antimony pentafluoride (20. g) and tetrafluoro- ethylene (TFE, 50 g) were added to a 400 mL HastelloyN nickel alloy shaker tube. The reaction mixture was agitated at 50°C for 12 hours. At this time addtional TFE (50 g) was added to the reaction mixture and agitation was continued for 12 hours at 50°C. The product isolated was polytetrafluoroethylene (PTFE, 20 g) along with recovered CF3CF2CH2F (32 g).