Patent ID: 8080676

Claim:
A method for producing S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid in an aqueous solvent by hydrolysis of an S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid ester represented by general formula (1), which comprises (A) hydrolyzing an S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid ester represented by general formula (1) under a basic condition for 1-3 hours, then (B) removing insoluble matters contained in the reaction solution resulting from the hydrolysis, and (C) adding an acid to the resulting solution under a temperature condition of 50-80° C. to effect crystallization wherein R in general formula (1) represents an alkyl group or aryl group.