Enantioselective Synthesis of Functionalized Nitrocyclopropanes by Organocatalytic Conjugate Addition of Bromonitroalkanes to α,β-Unsaturated Enones
作者:Jian Lv、Jiaming Zhang、Zhu Lin、Yongmei Wang
DOI:10.1002/chem.200801651
日期:2009.1.12
A general enantioselective synthesis of functionalized nitrocyclopropanes by organocatalytic conjugate addition of a variety of bromonitroalkanes to α,β‐unsaturated enone systems is presented. The process, efficiently catalyzed by the salts of 9‐amino‐9‐deoxyepiquinine 1 d serves as a powerful approach to the preparation of synthetically and biologically important cyclopropanes with high levels of
提出了通过将各种溴硝基烷烃有机共轭加成到α,β-不饱和烯酮体系中来官能化硝基环丙烷的一般对映选择性合成方法。该过程可通过9-氨基-9-脱氧表奎宁1 d的盐有效催化,是制备具有高对映异构和非对映异构选择性的合成和生物学上重要的环丙烷的有力方法。由于仅使用0.6当量的溴硝基甲烷作为试剂,通过使用手性1 d作为其动力学拆分的高效催化剂,对映体纯(S)-2 e(97% ee在51%转化率下,选择性s = 120) 。