New asymmetric process for the preparation of diarylmethylpiperazines derivatives and novel asymmetric diarylmetylamines as intermediates

摘要

An asymmetric synthesis of diarylmethylpiperazines derivatives is described. The synthetic route enables preparation of a variety of enatiomerically pure amines with different N -alkyl groups. The method involves an asymmetric addition of organometallic compounds to chiral sulfinimine to give adducts in predominantly one diastereomeric form. After purification by chromatography or crystallization the pure diastereomer can subsequently be transferred into the corresponding pure enantiomers by cleavage of the chiral auxilliary which is followed by synthesis of the piperazine ring by alkylation procedures.