作者:Weiye Guan、Samantha O. Santana、Jennie Liao、Kelci Henninger、Mary P. Watson
DOI:10.1021/acscatal.0c04223
日期:2020.12.4
An enantioselective copper-catalyzed alkynylation of unstabilized cyclic iminium ions has been developed. Whereas such alkynylations typically utilize pyridinium, quinolinium, and isoquinolinium intermediates, this method enables use of cyclic iminium ions unstabilized by resonance. With the use of a Lewis acid and copper catalyst, these iminium ions are generated in situ from readily available hemiaminal
已开发出不稳定的环状亚胺离子的对映选择性铜催化炔基化反应。虽然此类炔基化通常使用吡啶鎓、喹啉鎓和异喹啉鎓中间体,但该方法能够使用通过共振不稳定的环状亚胺鎓离子。通过使用路易斯酸和铜催化剂,这些亚胺离子由容易获得的半缩醛胺甲基醚原位生成,并转化为高度对映体富集的α-炔基化环胺。可以高产率和对映体过量掺入各种末端炔烃。