FORMULATION"

TECHNICAL FIELD

The present invention relates to novel metal/boron co-ordination compounds as biocides, methods of synthesis of metal/boron co-ordinating compounds, their use as biocides and/or as stripping agents and their formulation.

BACKGROUND

Many biocides used internationally are being seriously questioned due to their toxicity and severe environmental impact.

In the areas of both agricultural fungicides and timber preservation alternatives to traditional products are being proposed. To remain commercially viable companies must reflect on these changes and produce suitable alternatives.

In timber preservation the dominant preservative used is Copper Chrome Arsenate (CCA). This and other products are under serious attack and may decline in use for political as well as environmental reasons.

The dominant timber preservatives used internationally are shown in the following table together with annual turnover expressed in 1993 US dollars.

Table 1

(US$ Million) Copper Chrome Arsenate 212

LOSP (TBTO, PCP etc.) 42 Creosote 240

494

During recent years all of these products have been questioned primarily due to toxicity to mammals however, environmental impact has been increasingly recognised as an issue and will certainly curtail the use of these products in some markets in future. A brief comparison of acute properties is shown in the following table.

Table 2

RELEVANT REFERENCES

In the publication "BOR in Biologie, Medizin und Pharmazie - Physiologische Wirkungen und Anwendung von Borverbindungen, their method of Synthesis, their Use and their Formulation" by Wolfgang Kliegel (Springer- Verlag, Berlin Heidelberg New York 1980) is a disclosure of a number of moieties of boron which are anionic in nature and can be bonded to a metal cation or an ammonium cation. Such anionic boron moieties disclosed are monovalent.

In European Patent Specification EP0361893A3 (Maynard) there is disclosed a method of preparing a compound or formulation having biocidal or preservative properties where a metal cationic species is complexed with anionic organo boron moieties. These were believed to be of a structure as follows,

Formula I

where R and R' are independently selected from the group consisting of hydrogen, halogen, cyclopentyl, cyclohexyl, and phenyl substituents and aliphatic radicals of 1 to 15 carbon atoms.

DISCLOSURE OF INVENTION

The present invention relates to specific ranges of coordinated compounds that embody both a boron presence and a metal presence and have an ability to fix each of the biologically effective elements by providing an appropriate solvent delivery system which positions the compound and then allows both of the elements to be fixed by appropriate degradation when delivered into, say, timber or other matrix (eg; the resin or an antifouling paint) capable of being susceptible to biological act (eg; fungal or insectidical).

The present invention in another aspect utilises the method of synthesis of the present invention to strip ligand forming moieties and/or multivalent cations from a liquid stream,

In one aspect the present invention is a process for synthesising a neutral compound having a multivalent metal cation or cations (hereafter "target cation(s)) and boron containing complex organic anions, and optionally ligands, said process comprising

A i) reacting with a diol or triol

(a) a borate without target cation(s),

(b) a multivalent metal borate with target cation(s) but no ligands, or

(c) a multivalent metal borate with target cation(s) and with ligands, or ii) reacting boric acid with a diol or triol, or iii) reacting boric anhydride with a diol or triol, AND B) where the target cation(s) is or are not already associated, associating the boron containing complex organic anion procured by (A) (i)(a), (ii) and/or (iii) with at least one source of the target cation(s), step B) being performed

(a) in a source of ligand(s) not already complexed to the metal target cation(s) nor the boron containing complex organic anion, or (b) with a source of the metal target cation(s) already complexed with ligands,

AND/OR

C)(i) optionally presenting the product of step A(i)(c) or (B) to a source of stronger ligands, or,

(ii) presenting the product of step A(i)(b) to a source of ligands, AND D) optionally, removing the ligands by heating, AND

E) optionally, where step D is performed, subsequently attaching ligands to the ligand free product of step D) provided however, where step A is A(i)(a) or (b) or A(ϋ), and one of steps C(i), D and E is not being performed, the metal cation cannot be copper, zinc, barium, sodium, potassium, magnesium, calcium, iron, manganese, cobalt, or nickel, the anion cannot be

, and the ligands, if any, cannot both or all be H ₂ 0.

Preferably said diol or triol of step A(i), (ii) or (iii) is selected from the group consisting of naphthalene diols, phenyl glycols, glycerol ether diols, dihydroxy phenyl diols, dihydroxy anthracene diols, methylol phenols, methylol naphthols, methylol anthrols, aliphatic 1, 2 diols, aliphatic 1, 3 diols and triol monoesters. Preferably said target cation is a transition metal or an alkali earth metal.

Preferably said ligand(s) (branched or otherwise) is or are selected from the group comprising H ₂ 0, Nlf , pyridine, alkylamines (substituted or non substituted) and ethylenediamine.

In one form said neutral compound results from steps A(i)(a) and B(a). In another form said neutral compound results from steps A(i)(a) and B(b).

In yet another form said neutral compound results from step A(i)(b).

In another form said neutral compound results from steps A(i)(c).

In another form said neutral compound results from steps A(ii) and B(a).

In yet another form said neutral compound results from steps A(ii) and B(b). In another form said neutral compound results from steps A(iii) and B(a).

In even another form said neutral compound results from steps A(iii) and B(b).

In another form neutral compound results from steps A(i)(b) and C(ii).

In one aspect the inventive process includes step D and the neutral compound has the ligands removed. In another embodiment the neutral compound is provided using step E.

Preferably any ligands attached by step C(i) and/or E are other than H ₂ 0.

Preferably the anion is

Formula I

where R and R' are independently selected from the group consisting of hydrogen, halogen, cyclopentyl, cyclohexyl, and phenyl substituents and aliphatic radicals of 1 to 15 carbon atoms.

Preferably the anion is

Formula IA

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Preferably said target cation is selected from the group comprising copper, cobalt, nickel and manganese in the II valency state and the neutral compound has at least one ligand and has at least a reasonable aliphatic solubility and a low water solubility.

Preferably the neutral compound is of the formula

and M, A, Lβ and L _c is one of the following:

In another aspect the invention is a neutral compound having a multivalent metal cation or cations, boron containing complex organic anions and, optionally, ligands when that product has been produced by a process of the present invention.

In another aspect the invention is a biocidal composition comprising an effective amount of a neutral compound of the present invention and an organic solvent therefor.

In one form the composition is a micro suspension in an aqueous carrier.

In a further aspect the invention is a biocidal compound having a low solubility in water at ambient temperatures and non extreme pH conditions and which is substantially neutral, said compound comprising a multivalent metal cation, a plurality of borate organic complex anions, and

, optionally, two or more electron donating ligands, provided however, when the metal cation is copper, zinc, barium, sodium, potassium, magnesium, calcium, iron, manganese, cobalt or nickel, the anion cannot be

and the ligands, if any, cannot both or all be H ₂ 0.

Preferably said multivalent metal cation is selected from the group consisting of transition metals and alkali earth metals.

Preferably said multivalent metal cation is selected from divalent or greater valiant cations of the metals copper, cobalt and nickel.

Preferably said borate organic complex anion is of the general formula.

Formula IA

Preferably said borate organic complex anion is the boronato moiety having the formula

Formula π

In another aspect the invention is a biocidal composition comprising a biocidal compound as previously defined.

Preferably said non aqueous solvent is an aliphatic solvent.

Preferably said composition is co-formulated with a surfactant or surfactants having an HLB between 3 and 19.

In one form the composition is in the form of a solution.

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In another form the composition s in the form of an emulsion.

In another aspect the invention consists in a compound having the formula

where A is an integer 2 or more, M is a metal element, 1^ is an election donating ligand or a pair or such ligands (the same or different), independently of Lβ, L _c is an electron donating ligand or a pair of such ligands (the same or different), and wherein the boronato anionic moieties (the same or different) may be organically bridged or not.

Preferably M is a transition metal.

In other form M is an alkali earth metal

Preferably M is copper, cobalt or nickel.

Preferably the anionic boronato moiety has the formula

Formula IA

Preferably Lβ and L _c are two ligands preferably the same. Preferably Lβ and L _c are other than H ₂ 0.

Preferably Lg and L _c are NH ₃ , or an organic amine (eg isopropylamine, tettaethanolamine or bridged ethylenediamine) or pyridine. In a further aspect the invention consists in a method of preserving timber or wood using a compound of the present invention or a compound made and/or solubilised by a process of the present invention.

In still a further aspect the invention is a method of removing a ligand forming moiety from an aqueous media which comprises stripping the ligands from the aqueous phase into an organic phase, using a multivalent metal boronate complex (step B(a) or step

B(b) or step C(i) or step C(ii) or step E or the ligands then optionally being removed by heat and/or reduced pressure to allow recycle of the stripping agent, the stripping agent being one of the aforementioned multivalent metal boronate complexes.

In still a further aspect the invention comprises recovering metal cations from an aqueous medium which comprises performing step A(i)(b) or A(i)(c) or B(a) or B(b) or

C(i) or C(ii) in an aqueous stream having multivalent metal cations and stripping such cations into an organic phase upon movement of the complex into the organic phase.

In still a further aspect the invention is a biocidal use of a compound of the present invention or a compound made and/or solubilised by a process of the present invention. The borate organic complex ions of the invention are made by reacting borates, boric acid or boric anhydride with a suitable diol or triol eg; preferably 1, 2 or 1, 3 diols.

Examples of suitable diols and triols include: 1. Naphthalene Diols: For example:

OH OH

R R' Formula m

where R,R' are independently selected from the group consisting of hydrogen, halogen and aliphatic radical of 1 to 8 carbon atoms; b)

Formula IV

where R is defined as above;

2. Phenyl Glycols

For example:

a) OH OH

R' R" Formula V

where R is selected from the group consisting of hydrogen, halogen and aliphatic radicals of 1 to 15 carbon atoms; and R' is selected from the group consisting of hydrogen and aliphatic radicals of 1 to 8 carbon atoms and R" is selected from the group consisting of hydrogen, and aliphatic radicals of 1 to 8 carbon atoms, and phenyl substituents;

Formula VI

where R is selected from the group consisting of hydrogen and aliphatic radicals of 1 to

8 carbon atoms; and R ¹ is selected from the group consisting of hydrogen and aliphatic radicals of 1 to 8 carbon atoms.

3. Glycerol Ethers

For example: a)

Formula Vπ

where R is selected from the group consisting of saturated and unsaturated aliphatic radicals of 1 to 15 carbon atoms; b)

Formula VID

where R, R' are independently selected from the group consisting of hydrogen, halogen, aliphatic radicals of 1 to 10 carbon atoms and halogen substituted aliphatic radicals of 1 to 10 carbon atoms. 4. Dihydroxy Phenyl Compounds For example:

Formula DC

where R is an aliphatic radical of 1 to 15 carbon atoms, or is phenyl or cyclohexyl. S. Dihydroxy Anthracene Compounds For example:

Formula X

where R, R' are independently selected from the group consisting of hydrogen, halogen and aliphatic radicals of 1 to 8 carbon atoms. 6. Methylol Phenols, Methylol Naphthols, Methylol Anthrols For example: a)

Formula XI

where R, R' are independently selected from the group consisting of hydrogen, halogen, cyclopentyl, cyclohexyl, phenyl and aliphatic radicals of 1 to 15 carbon atoms;

Formula XII

where R is selected from the group consisting of aliphatic radicals of 1 to 15 carbon atoms, phenyl and cyclohexyl substituents;

c)

Formula Xm

where R,R',R", are independentiy selected from the group consisting of hydrogen, halogen and aliphatic radicals of 1 to 8 carbon atoms;

where R,R',R",R" are independently selected from the group consisting of hydrogen, halogen and aliphatic radicals of 1 to 8 carbon atoms. 7. Aliphatic 1, 2 Diols

For example:

Formula XV

where R,R',R",R'" are independently selected from the group consisting of aliphatic radical of 1 to 8 carbon atoms, cyclohexyl and cyclopentyl substituents.

8. Aliphatic 1, 3 Diols

For example:

Formula XVI

where R,R',R",R"' are independently selected aliphatic radicals of 1 to 8 carbon atoms. 9. Triol Monoesters

For example:

Formula XVπ

where R,R',R" are independently selected aliphatic radicals of 1 to 15 carbon atoms. To the extent only that the synthesis of EP0361893A3 discloses a compound of foπnula

Formula XVm

the present invention preferably excludes that compound per se. Likewise preferably the bisaquo compound of that formula (XVIII) if the example given in EP0361893A3 inevitable produces the version thereof with two H ₂ 0 ligands.

Even if EP0361893A3 is an anticipation of these compounds per se the present invention includes the new methods of synthesis thereof included herein.

The reality is that there is no actual bond between the B atoms and the copper or other metal atom. The charge on the M or copper is neutralised by dative bonds from the ligands.

le:

and the overall charge kept neutral by the boronate ligand eg:

It is believed in addition to M ²⁺ , higher oxidation states can exist as in

and so on. In the reality therefore the complex is a neutral compound (overall) of metal plus ligand in neutral stoichiometry with boronate ions.

The borate organic complex ion and the metal cation borate complex ion compound formed by the invention or being the invention has preferably low solubility in aqueous systems under normal conditions of pH and temperature. Each of the ligands is a one or more electron donating moiety including but not restricted to; H ₂ 0, NH ₃ , pyridine, alkylamines or many other ligands known to those versed in the art. The ligand may comprise of a bridged or bridging ligand (wherein the ligand may contain two or more electron donating groups eg ethylenediamine).

Also within the scope of the present invention is the anhydrous or ligand free metal borate organic complex ion compound other than those specifically disclosed in

EP0361893A3.

In a further aspect the invention comprises a phase transfer agent based on a borate organic complex ion wherein extraction from aqueous systems into solvent systems of a metal ion is assisted by the addition of electron donating ligands to neutralise or diffuse the charge on the metal ion.

According to another aspect of the invention the borate organic complex ion is synthesised by reacting simple borates such as sodium borate, boric acid or boric anhydride with a suitable 1,2 or 1,3 diol etc. The complex ion is then reacted with a second cation eg copper etc. This creates the family of bisaquo species with only two ligands (eg L ¹ and L ² ) and each is H ₂ 0.

The present invention encompasses the bisaquo species then being reacted with a stronger ligand (eg NH ₃ ) to yield a new species.

In this sequence of the present invention strong ligands can replace previously weaker ligands.

The invention further comprises a process step where a bis ligand species is decomposed by heating and subsequently ligands are reattached using the same or different ligands or ligand/solvent systems.

According to another aspect of the invention a non simple borate (not sodium borate, boric acid) or effectively aqueous insoluble borate (eg copper borate) is reacted with an organic complexing agent in the presence of a suitable solvent to form the metal borate organic complex ion compound.

A strong ligand is added in low concentration to assist with the initial aqueous solubilisation of the metal borate prior to formation of the metal borate organic complexion compound. This is particularly suitable for synthesis of bis aquo species. eg

An example of an alkali metal complexing agent is

The simple borate organic complex ion can be reacted with a second cation (eg copper) in the presence of a ligand other than water (eg NH ₃ ).

The metal ion can be complexed with a suitable ligand prior to addition to the simple borate organic complex ion (eg Cu B ₂ 0 ₈ 4NH3 Cu(NH ₃ ) ₄ B ₂ 0 ₈ ). >

The non simple or aqueous insoluble borate is solubilised with a suitable ligand

prior to reaction with organic complexing agent or its alkali metal salt.

The invention also comprises a method of manufacture of anhydrous or ligand free

metal borate organic complex ion compound by heat removal of volatile ligands, (eg

water, NH ₃ ).

Typical Chemistry

For convenience only two Boronato moieties shown.

The present invention also consists in a method of synthesis of a desired compoun

of formula (II) using a synthesis selected from the analogous routes for a compound jus

previously set forth where the Boronato complex is as in Formula 1 A.

Typical Bis Boronate Bis Ligand Metal Complexes

The synthesis procedures of EP0361893A3 have a yield potential of no greater tha about 50% while those of the present invention are from 50% to about 80%.

Since the preferred moiety has low solubility in water, it is sometimes preferred t make the product miscible eg when using as an alternative to CCA in water.

It has been found that by selecting suitable solvents (eg isopropanol) and c formulating with suitable surfactants (HLB between 3 and 19) the product will produc a clear emulsion or solution.

The present invention also consists in such formulations of compounds per se of the present invention as well as any of those disclosed by a synthesis in EP0361893A3. Examples of Metal Boronate Synthesis

The following synthesis utilised 82% pure Chloromethylolnonylphenol (CMNP) Example 1

34.6 gm (0.1 mol) technical CMNP is dissolved in 50 gm aliphatic white spirit.

This is reacted at ambient temperature with 3.64 gm (0.0125 mol) Sodium Tetraborate Pentahydrate in 200 mil water.

Upon completion the organic phase is triturated with 6.24 gm (0.025 mol) of Copper Sulphate Pentahydrate dissolved in 50 ml water.

The reaction progress can be followed by red-brown colour development in the organic phase.

The yield of the reaction is determined by atomic absorption spetrosponic analysis of the copper content. Copper content of the organic phase is determined at 3.17% giving a yield of 76%.

Example 2

34.6 gm (0.1 mol) technical CMNP is dissolved in 50 gm aliphatic white spirit. This is reacted at ambient temperature with 3.64 gm (0.0125 mol) Sodium Tetraborate Pentahydrate in 200 ml water. Upon completion the organic phase is triturated with 6.24 gm (0.025 mol) of Copper

Sulphate Pentahydrate dissolved in 50 ml water.

The reaction progress can be followed by red-brown colour development in the organic phase.

To tiie reaction mixture was added 6.1 gm (0.1 mol) Ethanolamine. Upon reaction the organic phase becomes deep green.

The yield of the reaction is determined by atomic absorption spectroscopic analysis of the copper content.

Copper content of the organic phase is determined at 1.41% giving an overall yield of 33%

It was determined that competition from competing protons from the acidic Copper sulphate was decreasing the yields therefore neutral species such as Cupric tetiaammine sulphate was tried. Example 3 34.6 gm (.01 mol) technical CMNP is dissolved in 50 gm aliphatic white spirit.

This is reacted at ambient temperature with 3.64 gm (0.0125 mol) Sodium Tetraborate Pentahydrate in 200 ml water.

Upon completion the organic phase is triturated with 6.24 gm (0.025 mol) of Copper Sulphate Pentahydrate dissolved in 50 ml water to which 6.8 gm of 25% ammoma solution had been added.

The reaction progress can be followed by green colour development in the organic phase.

Analysis by Kieldahl distillation indicated 0.1 mol NH3 was complexed in the organic phase. To the reaction mixture was added 6.1 gm (0.1 mol) Ethanolamine. Upon reaction the organic phase becomes deep green.

The yield of the reaction is determined by atomic absorption spectroscopic analysis of the copper content.

Overall yield was determined at 88%. Example 4

34.6 gm (0.1 mol) technical CMNP is dissolved in 50 gm aliphatic white spirit.

Upon completion the organic phase is triturated with 3.7 gm (0.025 mol) of Copper Borate suspended in 50 ml water.

The reaction progress can be followed by red-brown colour development in the organic phase.

The yield of the reaction is determined by atomic absorption spectroscopic analysis of the copper content was 93% Example 5

A sample taken from that produced in example 1 was reacted with 0.05 mol of Pyridine.

The organic solution reacted to produce the pink bipyridinium complex without any loss copper. Example 6

A sample produced in example 1 was heated to remove associated water of hydration.

The compound lost the red-brown colouration forming a grey-green complex.

Upon addition of ammonia the green tetiaammine complex was formed.

Similar procedures have exhibited similar yield for the other multivalent cations hereinbefore described.

Comparison of Metal Borate complexed in the control of growth of the decay fungus Coniophora puteana.

A rapid screening process was set up to compare the bioperformance of a ligand containing Copper complex synthesised by the present invention (is; the bis aquo copper boronate complex) against a similar Copper complex product obtained from the synthesis of EP0361893 A3. The test involved a measurement of inhibition of growth of the test fungus Coniophora puteana on cellulose paper.

Results means colony diameter (2 weeks @ 25 °C)

The results indicate similar performance within experiment error. As a consequence a biocidal efficacy (see EP0361893A3) is exhibited when the compounds of the present invention are introduced onto and/or into a matrix (eg; wood, paint, composite, materials, etc) and such biocidal effect is enhanced where the multivalent cation is also biocidal.

In the aforementioned EP0361893A3, the full content of which is hereby here incorporated by reference, there is depicted therein in Table I and Table II details of the use of a biocidal multivalent cation such as copper in addition to a boron delivering organic complex ion boron salt. The present invention also envisages the selective usage of parts or stages of the synthesis process of the present invention in an aqueous medium containing either a ligand source or a source of multivalent metal cations thereby tying the ligand forming moieties or multivalent metal cations into an intermediate or end point complex form as is produced by a method of synthesis in accordance with the present invention. Then by appropriate procedures it is easy to move the complex and thus the stripped component

(picked up by the remainder of the complex acting as a stripping agent) into an organic phase. By way of example as previously stated the aqueous phase could be treated and then be mixed with the organic phase after there has been sufficient time for the various attachments to take place whereupon by simple separation processes (eg; decanting) the organic phase containing a complex in accordance with the present invention will then be separated from the stripped or at least partly stripped aqueous medium. For ligand recovery is some instances the complex can be heated.