Efficient resolution of (±)-trans-2,3-diphenylpiperazine using (1S)-(+)10-camphorsulfonic acid and enrichment of enantiomeric purity of non-racemic 2,3-diphenylpiperazine using different achiral acids

Abstract

Enantiomerically pure (R,R)-(+)-2,3-diphenylpiperazine with 98% ee was obtained by resolution of the corresponding racemic mixture using (15)-(+)-10-camphorsulfonic acid. The partially resolved enriched sample of (S,S)-(-)-2,3-diphenylpiperazine with 73% ee was purified to obtain samples of 97% ee using different achiral acids via the preparation of either homochiral or heterochiral hydrogen bonded aggregates. © Indian Academy of Sciences.