A new method for the preparation of unsymmetrical 1,4-substituted piperazine derivatives
作者:Aurelio Ortiz、Norberto Farfán、Herbert Höpfl、Rosa Santillan、Marı́a E. Ochoa、Atilano Gutiérrez
DOI:10.1016/s0957-4166(99)00049-x
日期:1999.2
Symmetrical and unsymmetrical N,N′-piperazine derivatives of (−)-norephedrine and o-aminophenol were synthesized stereoselectively in yields >70% by reduction of the corresponding N,N′-ethylenebisoxazolidine heterocycles. The stereochemistry at the ring fusion carbons was established by NMR spectroscopy and X-ray crystallography.