PROCESS FOR RUTHENIUM-CATALYZED TRANSVINYLATION OF CARBOXYLIC ACIDS

Abstract

The invention relates to a process for transvinylation of a carboxylic acid feedstock with a vinyl ester feedstock to obtain a vinyl ester product and the corresponding acid of the vinyl ester feedstock in the presence of one or more ruthenium catalysts, wherein a) the vinyl ester feedstock, the carboxylic acid feedstock and a ruthenium catalyst are fed to the reactor, and b) the transvinylation reaction is carried out, characterized in that a carbonyl-free Ru(III) carboxylate is used as the ruthenium catalyst and in that no carbon monoxide is supplied, c) the reaction is carried out at a temperature of 110 to 170 C., d) upon completion of the transvinylation reaction, the vinyl ester feedstock and the corresponding acid are separated from the reaction mixture by distillation, e) the vinyl ester product is separated by distillation from the bottom product of the distillation, and f) the remaining reaction mixture is recycled into the reactor.

Claims

1. A process for transvinylation of a reactant carboxylic acid with a reactant vinyl ester to afford a product vinyl ester and the corresponding acid of the reactant vinyl ester in the presence of one or more ruthenium catalysts, wherein a) the reactant vinyl ester, the reactant carboxylic acid and a ruthenium catalyst are supplied to the reactor, and b) the transvinylation reaction is performed, wherein the ruthenium catalyst employed is a carbonyl-free Ru(III) carboxylate and no carbon monoxide is supplied, c) the reaction is performed at a temperature of 110 C. to 170 C., d) after completion of the transvinylation reaction the reactant vinyl ester and the corresponding acid are distillatively removed from the reaction mixture, and e) the product vinyl ester is distillatively removed from the bottoms product of the distillation, and f) the remaining reaction mixture is recycled into the reactor.

2. The process as claimed in claim 1, wherein the residence time in the reaction zone is 0.25 to 5 hours.

3. The process as claimed in claim 1, wherein the reaction is performed at a temperature of 120 C. to 150 C.

4. The process as claimed in claim 1, wherein the ruthenium catalyst employed is [Ru.sub.3O(OAc).sub.6(H.sub.2O).sub.n(AcOH).sub.3-n]OAc where n=0 to 3 or [Ru.sub.3O(OAc).sub.6]OAc.

5. The process as claimed in claim 4, wherein the ruthenium catalyst employed is a solution, in each case in acetic acid, of [Ru.sub.3O(OAc).sub.6(H.sub.2O).sub.n(AcOH).sub.3-n]OAc where n=0 to 3 or [Ru.sub.3O(OAc).sub.6]OAc.

6. The process as claimed in claim 1, wherein the reactant vinyl ester employed is a vinyl carboxylate ester of general formula RC(O)OCHCH.sub.2, wherein R is an aliphatic radical having 1 to 12 carbon atoms or is a cycloaliphatic radical having up to 12 carbon atoms or is an aromatic radical having up to 12 carbon atoms.

7. The process as claimed in claim 1, wherein the reactant vinyl ester employed is vinyl acetate.

8. The process as claimed in claim 1, wherein the reactant carboxylic acid employed is a carboxylic acid of general formula RCOOH, wherein R is an aliphatic radical having 1 to 22 carbon atoms or is a cycloaliphatic radical having up to 22 carbon atoms or is an aromatic radical having up to 22 carbon atoms.

9. The process as claimed in claim 1, wherein the reactant carboxylic acid employed is a carboxylic acid selected from the group consisting of Versatic acids and neo acids, each having 9 to 12 carbon atoms, and fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid.

10. The process as claimed in claim 1, wherein an anhydride of the respective reactant carboxylic acid is added as a reactant.

Description

EXAMPLES

[0042] the examples which follow serve to more particularly elucidate the invention.

[0043] The reported conversions relate in all cases to the starting component reactant carboxylic acid (2S) or reactant vinyl ester (1V) that is employed in a lesser molar fraction. The conversion is defined as U(%)=100(n.sub.0n.sub.E)/n.sub.0, wherein n.sub.0 is the amount of substance of the starting component at the beginning of the reaction and n.sub.E is the amount of substance at the end of the reaction.

Comparative Example 1

[0044] Transvinylation with Ru acetate solution as catalyst at 100 C.

[0045] In a 100 mL Berghoff autoclave 25.0 g (125 mmol) of lauric acid, 43.0 g (500 mmol) of vinyl acetate and 0.69 g (0.9 mmol) of [Ru.sub.3O(OAc).sub.6(H.sub.2O).sub.3]OAc (4.5 wt % Ru, dissolved in acetic acid from Umicore) were heated to 100 C. at 2.0 bar abs. for 6 hours.

Example 2

[0046] Transvinylation with Ru acetate solution as catalyst at 140 C.

[0047] In a 100 mL Berghoff autoclave 25.0 g (125 mmol) of lauric acid, 43.0 g (500 mmol) of vinyl acetate and 0.69 g (0.9 mmol) of [Ru.sub.3O(OAc).sub.6(H.sub.2O).sub.3]OAc (4.5 wt % Ru, dissolved in acetic acid from Umicore) were heated to 140 C. at 6.0 bar abs. for 5 hours.

[0048] In both cases samples were taken at defined time intervals and the molar fractions in the reaction mixture required for calculating conversion were determined by means of quantitative NMR spectroscopy.

TABLE-US-00001 Lauric acid conversion [%] comp. ex. 1 ex. 2 Time [h] 100 C. 140 C. 0 0 0 1.5 0.9 78.4 3 1.6 79.7 4.5 2.6 79.3

[0049] The example shows that when ruthenium acetate solution is used as catalyst at a temperature of 140 C. the catalytically active species is formed within residence times of less than 5 hours. The equilibrium state is reached after as little as 1.5 hours.