Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
J Am Chem Soc. 2010 Mar 24;132(11):3666-7. doi: 10.1021/ja1002636.
Direct catalytic asymmetric vinylogous reactions of an alpha,beta-unsaturated gamma-butyrolactam as a donor are described. A homodinuclear Ni(2)-Schiff base complex promoted a vinylogous Mannich-type reaction of N-Boc imines as well as a vinylogous Michael reaction to nitroalkenes selectively at the gamma-position under simple proton-transfer conditions. Vinylogous Mannich adducts were obtained in 5:1-->30:1 dr and 99% ee, and vinylogous Michael adducts were obtained in 16:1-->30:1 dr and 93-99% ee.
描述了一种作为供体的α,β-不饱和γ-丁内酯的直接催化不对称烯醇式反应。双核 Ni(2)-席夫碱配合物在简单的质子转移条件下,选择性地在γ-位促进 N-Boc 亚胺的烯醇式 Mannich 型反应以及与硝基烯烃的烯醇式 Michael 反应。烯醇式 Mannich 加合物以 5:1-->30:1 dr 和 99%ee 获得,而烯醇式 Michael 加合物以 16:1-->30:1 dr 和 93-99%ee 获得。