Alternative synthesis of α-substituted β-amidophosphines by [1,4]-addition. A new route to chiral ligands
作者:Matthieu Léautey、Géraldine Castelot-Deliencourt、Philippe Jubault、Xavier Pannecoucke、Jean-Charles Quirion
DOI:10.1016/s0040-4039(02)02250-5
日期:2002.12
Phosphine-borane can be diastereoselectively added to chiral alpha,beta-unsaturated amides 3, using amino-alcohols as chiral inducers, leading to alpha-substituted beta-amidophosphine boranes 4 with up to 74% diastereomeric excess. Selective deprotection afforded optically pure carboxylic derivatives 5 which are key intermediates for the synthesis of various potential chiral ligands for asymmetric catalysis. (C) 2002 Published by Elsevier Science Ltd.