Patent ID: 7166750
Filing Date: 2007-01-23
Classification: C07C

Abstract:
1. A process for producing 5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone, comprising: (1) reacting dimethyl adipate or diethyl adipate with 0.9 to 1.0 mole of metal alkoxide per mole of dimethyl adipate or diethyl adipate; (2) after removing alcohol as produced therefrom in the presence of at least one aprotic solvent, having a boiling point of not less than 75° C., and is selected from the group consisting of an aromatic compound selected from benzene, toluene, xylene and chlorobenzene, and an ether-based compound selected from dimethoxy ethane and dioxane, and in the presence of a small amount of an aprotic polar compound selected from dimethyl sulfoxide, N-methylpyrrolidone, dimethyl imidazoline, dimethyl acetamide and dimethyl formamide, reacting the reaction product obtained with 0.9 to 1.1 moles of methyl halide per mole of dimethyl adipate or diethyl adipate charged in step (1); (3) after completion of the reaction, reacting the reaction product obtained with metal alkoxide wherein the amount of the metal alkoxide charged in step (3) is 0.9 to 1.0 mole based on one mole of dimethyl adipate or diethyl adipate charged in step (1); (4) after removing alcohol as produced therefrom in the presence of at least one aprotic solvent, having a boiling point of not less than 75° C., and is selected from the group consisting of an aromatic compound selected from benzene, toluene, xylene and chlorobenzene, and an ether-based compound selected from dimethoxy ethane and dioxane, and in the presence of a small amount of an aprotic polar compound selected from dimethyl sulfoxide, N-methylpyrrolidone, dimethyl imidazoline, dimethyl acetamide and dimethyl formamide, reacting the reaction product obtained with 0.9 to 1.0 mole of (4-chlorophenyl) methyl chloride per mole of dimethyl adipate or diethyl adipate charged in step (1); (5) reacting 1-[(4-chlorophenyl)methyl]-3-methyl-2-oxocyclopentanecarboxylic acid methyl ester or 1-[(4-chlorophenyl)methyl]-3-methyl-2-oxocyclopentanecarboxylic acid ethyl ester with sodium hydride and methyl halide wherein the amount of the sodium hydride used in this reaction is 1.0 to 1.3 moles based on one mole of the 1-[(4-chlorophenyl)methyl]-3-methyl-2-oxocyclopentanecarboxylic acid methyl ester or ethyl ester, and the amount of the methyl halide used is 1.0 to 1.3 moles based on one mole of the 1-[(4-chlorophenyl)methyl]-3-methyl-2-oxocyclopentanecarboxylic acid methyl ester or ethyl ester, and wherein the reaction is conducted in the presence of at least one aprotic solvent, which is non-reactive with sodium hydride or methyl halide, selected from the group consisting of an aromatic compound selected from benzene, toluene, xylene and chlorobenzene, an ether-based compound selected from tetrahydrofuran, dimethoxy ethane and dioxane, and an aprotic polar compound selected from dimethyl formamide, demethyl acetamide, N-methylpyrrolidone and dimethyl sulfoxide; and wherein after sodium hydride is added to the solvent, said ester and methyl halide are added to the solvent; and (6) hydrolyzing the obtained 1-[(4-chlorophenyl)methyl]-3,3-dimethyl-2-oxocyclopentanecarboxylic acid methyl ester or 1-[(4-chlorophenyl)methyl]-3,3-dimethyl-2-oxocyclopentanecarboxylic acid ethyl ester.