On the origins of enantioselectivity in oxazaborolidine mediated carbonyl reductions
摘要:
A series of tricyclic oxazaborolidine catalysts have been prepared from readily available (S)-indoline-2-carboxylic acid. In each case, an arene chromium(O) carbonyl group was introduced on one face of the catalyst. Results obtained in the borane mediated reduction of ketones highlight the stereodirective importance of the alpha, alpha-appendages in the catalyst architecture. (C) 1997 Published by Elsevier Science Ltd.