Catalytic Mechanism Study on the 1,2‐ and 1,4‐Transfer Hydrogenation of Ketimines and β‐Enamino Esters Catalyzed by Axially Chiral Biscarboline‐Based Alcohols
作者:Mengxian Dong、Jie Wang、Shijie Wu、Yang Zhao、Yangyang Ma、Yongfei Xing、Fei Cao、Longfei Li、Zhenqiu Li、Huajie Zhu
DOI:10.1002/adsc.201900665
日期:2019.10.8
Axial N‐O alcohols, which have two large carboline moieties connected to the axis were synthesized and used in catalytic enantioselective 1,2‐ and 1,4‐transfer hydrogenations of total 26 ketimines and β‐enamino esters. Excellent levels of enantioselectivity ranging from 91% to 99% were achieved by using catalyst (aS)‐(S)‐3,3′‐bis((S)‐2‐(hydroxymethyl)pyrrolidine‐1‐carbonyl)‐9,9′‐dimethyl‐9H,9′H‐[1
合成了具有两个与轴连接的大碳环部分的轴向N- O醇,并将其用于催化总共26种酮亚胺和β-烯胺酸酯的对映选择性1,2-和1,4-转移氢化。对映选择性为91%至99%的优异的水平通过使用催化剂(a实现小号) - (小号)-3,3'-双((小号)-2-(羟甲基)吡咯烷-1-羰基)-9, 9'-二甲基-9- ħ,9' ħ - [1,1'- bipyrido [3,4 b ]吲哚2-氧化物。有趣的是,(A混合物小号) - (小号)-3,3'-双((小号)-2-(羟甲基)吡咯烷-1-羰基)-9,9'-二甲基-9- ħ,9' ħ-[1,1'-联吡啶[3,4- b ]吲哚] 2-氧化物和(a R)-(S)-3,3'-bis((S)-2-(羟甲基)吡咯烷-1-羰基)-9,9'-二甲基-9- ħ,9' ħ - [1,1'- bipyrido [3,4 b ]吲哚2-氧化物也能够提供高对映体选择性高达95%也就是相同使用纯的(一个小号)