Metathesis of olefins using ruthenium based catalytic complexes

Abstract

A self-metathesis process for the production of unsaturated dicarboxylic fatty diacids and/or unsaturated dicarboxylic fatty diesters, wherein unsaturated carboxylic fatty acids and/or esters of unsaturated carboxylic fatty acids are reacted in the presence of at least one defined ruthenium based catalyst compound. A catalyst enhancer compound selected from a sacrificial catalyst or a non-catalyst enhancer may also be used. The process exhibits improved reaction times and/or the catalyst can be used at very low concentrations.

Claims

1. A self-metathesis process for the production of unsaturated dicarboxylic acids and/or unsaturated dicarboxylic acid diesters, wherein unsaturated fatty acids and/or esters of unsaturated fatty acids are reacted in the presence of at least one catalyst compound of Formula (I): ##STR00004## wherein L represents a neutral ligand; R.sup.1 represents hydrogen, C.sub.1 to C.sub.6 alkyl, C.sub.2 to C.sub.6 alkenyl, C.sub.2 to C.sub.6 alkynyl, C.sub.5 or C.sub.6 aryl, aralkyl, hydroxyl, C.sub.1 to C.sub.6 alkoxy, aryloxy, or arylalkoxy; a, b, c, and d each independently represent hydrogen, C.sub.1 to C.sub.6 alkyl, C.sub.1 to C.sub.6 alkoxy, C.sub.5 or C.sub.6 aryl, or an electron withdrawing group; X.sup.1 and X.sup.2 each independently represent anionic ligands; R.sup.2 represents a C.sub.1 to C.sub.6 alkyl, C.sub.5 or C.sub.6 cycloalkyl, C.sub.5 or C.sub.6 aryl, C.sub.1 to C.sub.6 alkoxy, aryloxy, arylalkoxy, or alkanone; wherein the reaction is performed in the absence of solvents or in the presence of a solvent consisting of hydrocarbons and/or alcohols, and wherein a catalyst enhancer compound is also present during the reaction, said catalyst enhancer compound being a non-catalyst enhancer that is a titanium based compound.

2. The process according to claim 1 wherein the level of conversion is at least 40 wt. %.

3. The process according to claim 1 wherein the time to reach equilibrium is less than 20 minutes.

4. The process according to claim 1 wherein the concentration of catalyst of Formula (I) is less than 100 ppm.

5. The process according to claim 4 wherein the concentration of catalyst of Formula (I) is less than 10 ppm.

6. The process according to claim 1 wherein the catalyst efficiency is less than 100.

7. The process according to claim 6 wherein the catalyst efficiency is less than 10.

8. The process according to claim 1 wherein the catalyst of Formula (I) retains over 75% of its activity after 30 minutes.

9. The process according to claim 1 wherein no chemical treatment of the feedstock or starting material to remove catalyst poisons is performed.

10. The process according to claim 1 wherein the unsaturated fatty acids and/or esters of unsaturated fatty acids starting material comprises (i) a peroxide level of less than 3 meq/kg, (ii) a water content of less than 0.05 wt %, (iii) a hydroxyl value of less than 0.05 mg(KOH).Math.g.sup.1, and/or (iv) an acid value of less than 0.10 mg(KOH).Math.g.sup.1.

11. The process according to claim 1 wherein the non-catalyst enhancer is selected from the group consisting of titanium (IV) methoxide, titanium (IV) ethoxide, titanium (IV) propoxide, titanium (IV) isopropoxide, titanium (IV) butoxide, titanium (IV) tert-butoxide, titanium (IV) 2-ethylhexoxide, titanium (IV) 2-ethyl-1,3-hexanediolate, titanium (IV) tetrachloride, titanium (IV) tetrabromide, titanium (IV) tetrafluoride, titanium (IV) tetraiodide, and mixtures thereof.

12. The process according to claim 1 wherein the concentration of the non-catalyst enhancer is 10 ppm to 1,000 ppm.

13. The process according to claim 1 wherein the catalyst compound is of Formula (I) and is selected from the group consisting of [1,3-bis(2,6-diisopropylphenyl)-2-imidazolidinylidene]dichloro [2-(1-methylacetoxy) phenyl]methyleneruthenium(II); [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro [2-(1-methylacetoxy) phenyl]methyleneruthenium(II); [1,3-bis(2,6-diisopropylphenyl)-2-imidazolidinylidene]dichloro[[2-(2-oxopropoxy) phenyl]methylene]ruthenium(II); [1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[2-(2-oxopropoxy) phenyl]methylene]ruthenium(II); ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-trifluoracetamido)benzyliden]]ruthenium(II)); ([1,3-bis(2,6-diisopropylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-trifluoracetamido)benzyliden]]ruthenium(II)); ([1,3-bis(2,6-diisopropylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-isobutoxyacetamido)benzyliden]]ruthenium(II)); ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-isobutoxyacetamido)benzyliden]]ruthenium(II)); ([1,3-bis(2,6-diisopropylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-ethylesteracetamido)benzyliden]]ruthenium(II)); and ((1,3-bis(2,6-diisopropylphenyl)-imidazolidin-2-yliden)((2-ethyl-3-oxo-3,4,-dihydr-2H-benzo[b][1,4]oxazin-8-yl)methylene)ruthenium(II)chlorid).

14. A process for improving the efficiency of the catalyst compound of Formula (I) in a self-metathesis process for the production of unsaturated dicarboxylic acids and/or unsaturated dicarboxylic acid diesters, wherein unsaturated fatty acids and/or esters of unsaturated fatty acids are reacted in the presence of at least one catalyst compound of Formula (I): ##STR00005## wherein L represents a neutral ligand that is a carbene ligand; R.sup.1 represents hydrogen, C.sub.1 to C.sub.6 alkyl, C.sub.2 to C.sub.6 alkenyl, C.sub.2 to C.sub.6 alkynyl, C.sub.5 or C.sub.6 aryl, aralkyl, hydroxyl, C.sub.1 to C.sub.6 alkoxy, aryloxy, or arylalkoxy; a, b, c, and d each independently represent hydrogen, C.sub.1 to C.sub.6 alkyl, C.sub.1 to C.sub.6 alkoxy, C.sub.5 or C.sub.6 aryl, or an electron withdrawing group; X.sup.1 and X.sup.2 each independently represent anionic ligands; R.sup.2 represents a C.sub.1 to C.sub.6 alkyl, C.sub.5 or C.sub.6 cycloalkyl, C.sub.5 or C.sub.6 aryl, C.sub.1 to C.sub.6 alkoxy, aryloxy, arylalkoxy, or alkanone; wherein the process comprises adding a catalyst enhancer to the reaction and wherein the reaction is performed in the absence of solvents or in a solvent consisting of hydrocarbons and/or alcohols.

15. The process according to claim 1, wherein L represents a carbene ligand.

Description

EXAMPLE 1

(1) 100 g methyl oleate (purified by aluminium-oxide treatment) was heated to 100 C. 13 ppm of ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-trifluoracetamido)benzyliden]ruthenium(II)) was dissolved in 1 ml toluene, and this was added to the methyl oleate.

(2) After 30 seconds 43.6% conversion was reached, and after 120 seconds the reaction equilibrium conversion was reached. The reaction mixture contained 24.8% 9-octadecene and 25.4% 9-octadecenedioic acid dimethyl ester. A catalyst efficiency value of 26 was achieved.

EXAMPLE 2

(3) 100 g methyl oleate (purified by aluminium-oxide treatment) was heated to 100 C. 37 ppm of ([1,3-bis(2,6-diisopropylphenyl)-2-imidazolidinylidene]dichloro[2-(1-methylacetoxy)phenyl]methyleneruthenium(II)) was dissolved in 1 ml toluene, and this was added to the methyl oleate.

(4) After 30 seconds the reaction equilibrium conversion was reached. The reaction mixture contained 25.3% 9-octadecene and 25.2% 9-octadecenedioic acid dimethyl ester. A catalyst efficiency value of 18.5 was achieved.

EXAMPLE 3

(5) 100 g methyl oleate (purified by aluminium-oxide treatment) was heated to 100 C. 63 ppm of ((1,3-bis(2,6-diisopropylphenyl)-imidazolidin-2-yliden)((2-ethyl-3-oxo-3,4,-dihydro-2H-benzo[b][1,4]oxazin-8-l)methylene)ruthenium(II)chlorid was dissolved in 1 ml toluene, and this was added to the methyl oleate.

(6) After 30 seconds the reaction equilibrium conversion was reached. The reaction mixture contained 25.1% 9-octadecene and 25.5% 9-octadecenedioic acid dimethyl ester. A catalyst efficiency value of 31.5 was achieved.

EXAMPLE 4

(7) 100 g methyl erucate (purified by aluminium-oxide treatment) was heated to 100 C. 105 ppm of ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-trifluoracetamido)benzyliden]]ruthenium(II) was dissolved in 1 ml toluene, and this was added to the methyl erucate.

(8) After 30 seconds the reaction equilibrium conversion was reached. The reaction mixture contained 20.6% 9-octadecene and 28.4% 13-hexacosanedioic acid dimethyl ester. A catalyst efficiency value of 52.5 was achieved.

EXAMPLE 5

(9) 100 g isopropyl oleate (purified by aluminium-oxide treatment) was heated to 100 C. 50 ppm of ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-trifluoracetamido)benzyliden]]ruthenium(II) was dissolved in 1 ml toluene, and this was added to the isopropyl oleate.

(10) After 30 seconds equilibrium conversion was reached. The reaction mixture contained 51.0% isopropyl oleate, 19.3% 9-octadecene and 23.0% 9-octadecenedioic acid di-isopropyl ester. A catalyst efficiency value of 25 was achieved.

EXAMPLE 6

(11) 100 g dodecyl oleate (purified by aluminium-oxide treatment) was heated to 100 C. 50 ppm of ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-trifluoracetamido)benzyliden]]ruthenium(II)) was dissolved in 1 ml toluene, and this was added to the dodecyl oleate.

(12) After 30 seconds the reaction equilibrium conversion was reached. The reaction mixture contained 54.5% dodecyl oleate, 8.8% 9-octadecene and 36.7% 9-octadecenedioic acid di-dodecyl ester. A catalyst efficiency value of 25 was achieved.

COMPARATIVE EXAMPLE

(13) A comparative prior art catalyst as disclosed in US 2011/0171147 was also tested. 100 ml methyl oleate (purified by aluminium-oxide treatment) was heated to 100 C. 250 ppm of ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidnyliden]-[2-[[(4-methylphenyl)imino]methyl]-4-nitrophenol]-[3-phenyl-1H-inden-1-ylidene]ruthenium(II)chlorid) was dissolved in 1 ml toluene, and this was added to the methyl oleate.

(14) After 2 hours 30% conversion was obtained, and after 6.5 hours 40.8% conversion was reached. The reaction mixture contained 20.6% dimethyldiester and 20.2% 9-octadecene. A catalyst efficiency value in excess of 97,500 was found with the prior art catalyst.

EXAMPLES 7 TO 9

(15) A number of examples were conducted using catalyst enhancer compounds (Ti(O.sup.iPr).sub.4) and BF.sub.3. The starting material was also treated with an antioxidant (TBHQ). The results are shown in Table 1.

(16) TABLE-US-00001 TABLE 1 Example 7 Example 8 Example 9 Methyl Oleate (g) 50 50 50 Catalyst (ppm) 5 3 5 Ti(O.sup.iPr).sub.4 (ppm) 200 200 0 BF.sub.3 (ppm) 0 0 200 Conversion 50% 46% 41%

(17) Catalyst used was ([1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinyliden]dichloro[(2-isopropoxy)(5-isobutoxyacetamido)benzyliden]]ruthenium(II)).

(18) Improvements were seen on addition of catalyst enhancer compound. In Example 8 addition of 200 ppm gave 50% conversion whilst using only 5 ppm of catalyst. Example 8 used lower concentration of catalyst (3 ppm) which resulted in 46% conversion. Example 9 shows use of BF.sub.3 as another catalyst enhancer compound with similar results.

(19) It is to be understood that the invention is not to be limited to the details of the above embodiments, which are described by way of example only. Many variations are possible.