Three novel catalysts based upon cyclic beta-aminophosphonate derivatives 1-3 were designed to catalyze the asymmetric Michael addition reactions of ketones to p-nitrostyrenes. Among the catalysts that have been prepared in this study, cyclic beta-aminophosphonic acid monoethylester 3 showed the highest catalytic ability, giving the corresponding Michael adduct in good yields, high enantioselectivities (up to 92% ee), and high diastereoselectivities (syn:anti up to 95:5). (C) 2010 Elsevier Ltd. All rights reserved.
Synthesis of phosphonic analog of (S)-homoproline
作者:O. O. Kolodyazhnaya、A. O. Kolodyazhnaya、O. I. Kolodyazhnyi