CONTINUOUS SEPARATION METHOD WITH LIQUID PARTICLE EXTRACTOR - ENANTIOSEPARATION OF (PLUS-OR-MINUS)-MANDELIC ACID

Continuous enantioseparation of (+/-)-mandelic acid was performed by dual-flow countercurrent extraction. The optimum extraction condition was calculated by a semi-empirical computational method. Use of the two-phase system composed of a 0.2 mM copper(II) acetate aqueous solution and butanol containing 10 mM N-dodecyl-L-proline copper(II) complex as a chiral separator allowed (+/-)-mandelic acid to be separated continuously. HPLC analysis showed that the (-)-form was extracted into the organic phase and the (+)-form was recovered from the aqueous extract with ee higher than 99.9%, at the stationary state.