Relay Catalysis by Achiral Borane and Chiral Phosphoric Acid in the Metal-Free Asymmetric Hydrogenation of Chromones
作者:Jingjing Chen、Bochao Gao、Xiangqing Feng、Wei Meng、Haifeng Du
DOI:10.1021/acs.orglett.1c03286
日期:2021.11.5
achiral borane and chiral phosphoric acid was successfully developed for the asymmetrichydrogenation of chromones, giving the desired products in high yields with up to 95% ee. Achiral borane and chiral phosphoric acid are highly compatible in this reaction. The achiral borane acts as a Lewis acid for the first-step hydrogenation, and the chiral phosphoric acid acts as an effective chiral proton shuttle
成功开发了一种非手性硼烷和手性磷酸的中继催化策略,用于色酮的不对称氢化,以高达 95% 的 ee 的高收率得到所需产物。非手性硼烷和手性磷酸在该反应中高度相容。非手性硼烷作为第一步氢化的路易斯酸,手性磷酸作为有效的手性质子穿梭来控制对映选择性。
Synthesis of Tetrasubstituted Enamines through Borane-Catalyzed Hydrogenations
作者:Zijia Zhang、Xiangqing Feng、Haifeng Du
DOI:10.1021/acs.orglett.3c03578
日期:2023.12.29
This paper describes a B(C6F5)3-catalyzed hydrogenation of β-substituted α,β-unsaturated imines by using as low as 0.2 mol % catalyst. A variety of tetrasubstituted enamines were afforded in 95–99% yields. It provides an efficient and facile way without the need for column chromatography purification.
本文描述了使用低至0.2 mol% 的催化剂进行B(C 6 F 5 ) 3催化的β-取代的α,β-不饱和亚胺的氢化反应。多种四取代烯胺的产率达到 95-99%。它提供了一种有效且简便的方法,无需柱色谱纯化。