Enamine protonation: A chiral diamine catalyzes an asymmetric Friedel–Crafts reaction through catalytic enantioselectiveprotonation of an enamine. This process can be applied to a range of α‐substituted acroleins and indoles with high yields of products and high enantioselectivity (up to 94 % ee). An OH/π interaction between H2O and the indole ring was found to play an important role in the transition
烯胺质子化:手性二胺通过烯胺的对映选择性质子化催化不对称的Friedel-Crafts反应。该方法可用于一系列α-取代的丙烯醛和吲哚,具有高收率和高对映选择性(最高94%ee)。的O H / H之间的π相互作用2 O和吲哚环,发现发挥在过渡状态中起重要作用(参见方案)。
METHOD FOR THE PREPARATION OF alpha-SUBSTITUTED ACRYL ALDEHYDES
申请人:Council of Scientific and Industrial Research
公开号:US20160083409A1
公开(公告)日:2016-03-24
The invention discloses simple and rapid method for the preparation of α-substituted acryl aldehydes. More particularly, the invention discloses a method for the preparation of α-substituted acryl aldehydes via a gold-catalysed [1,3] rearrangement of the allenyl ethers with a record turnover frequency of 4600 h
−1
at 0.05 mol % of the catalyst concentration in homogeneous gold(I) catalysis. The α-substituted acryl aldehydes synthesized by the instant process are used as building blocks in organic synthesis.
Chiral Primary Amine-Catalyzed Divergent Coupling of α-Substituted Acrylaldehydes with α-Diazoesters
作者:Zaikun Xue、Yao Li、Sanzhong Luo
DOI:10.1021/acscatal.0c02405
日期:2020.10.2
We report, herein, aminocatalytic coupling of α-substituted acrylaldehydes with α-diazoesters, leading to chemoselective C–H insertion or cyclopropanation depending on α-substituents of diazoesters. A chiral primary–secondary diamine catalyst derived from l-tert-leucine enabled the efficient promotion of both C–H insertion and cyclopropanation pathways in good yields and high enantioselectivities at