Patent ID: 6825378
Filing Date: 2004-11-30
Classification: C07B,C07C,Y02P

Abstract:
A process for the preparation of enantiomerically pure cyclohexylphenyl glycolic acid of R or S forms, said process comprising the steps of:a) treating cyclohexylphenyl ketone of formula (2) with an ylide in an anhydrous solvent for a time period of 4-8 hours at an ambient temperature to obtain &agr;-cyclohexylstyrene of formula (3); b) reacting &agr;-cyclohexylstyrene (3) obtained in step (a) with dihydroxylating agent and a chiral ligand selected from the group consisting of K2CO3, K3Fe(CN)6, phthalazine, pyrimidine phenanthryl, quinoxaline, p-chlorobenzoate and anthraquinyl groups, in t-BuOH, at a temperature range of âˆ’15Â° C. to an ambient temperature, for a time period of 12-18 hours, to obtain a chiral diol of formula (4); c) oxidizing the primary hydroxyl group of the chiral diol (4) with an oxidizing agent in an organic solvent at a temperature range of âˆ’80Â° C. to âˆ’50Â° C. to obtain an hydroxy aldehyde; and d) oxidizing the hydroxy aldehyde of step (c) with an oxidizing agent and a buffer to obtain an enantiomerically pure cyclohexylphenyl glycolic acid of formula (1).