Directing the Activation of Donor-Acceptor Cyclopropanes Towards Stereoselective 1,3-Dipolar Cycloaddition Reactions by Brønsted Base Catalysis
作者:Jakob Blom、Andreu Vidal-Albalat、Julie Jørgensen、Casper L. Barløse、Kamilla S. Jessen、Marc V. Iversen、Karl Anker Jørgensen
DOI:10.1002/anie.201706150
日期:2017.9.18
first stereoselective organocatalyzed [3+2] cycloaddition reaction of donor-acceptor cyclopropanes is presented. By using an optically active bifunctional Brønsted base catalyst, racemic di-cyano cyclopropylketones can be activated to undergo a stereoselective 1,3-dipolar reaction with mono- and polysubstituted nitroolefins. The reaction affords functionalized cyclopentanes with three contiguous stereocenters
极性末端:介绍了供体-受体环丙烷的第一个立体选择性有机催化的[3 + 2]环加成反应。通过使用旋光性双官能布朗斯台德碱催化剂,外消旋二氰基环丙基酮可以被活化,从而与单或多取代的硝基烯烃发生立体选择性的1,3-偶极反应。该反应以高产率和立体选择性提供具有三个连续的立体中心的官能化的环戊烷。