METHOD OF PRODUCING S-(-)-6-HYDROXY-2,5,7,8-TETRAMETHYLCHROMANE-2-CARBOXYLIC ACID AND PRODUCT OBTAINED BY THE METHOD

摘要

[PROBLEMS] To provide an industrially available method for efficiently producing S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid, which is excellent in solid/liquid separation properties and has a high purity, from an S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid ester and a product obtained thereby. [MEANS FOR SOLVING PROBLEMS] At a temperature condition of 50 to 80<SUP>o</SUP>C, (A) an S-(-)-6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid ester represented by the general formula (1) is hydrolyzed under basic conditions for 1 to 3 hours; then, (B) the insoluble matters contained in the liquid hydrolysis reaction mixture are removed; and (C) an acid is added to the treated solution thus obtained for crystallization; provided that R in the general formula (1) represents an alkyl group or an aryl group.