首页 | 本学科首页   官方微博 | 高级检索  
     


Catalytic Asymmetric C −H Functionalization under Photoredox Conditions by Radical Translocation and Stereocontrolled Alkene Addition
Authors:Chuanyong Wang  Dr. Klaus Harms  Prof. Dr. Eric Meggers
Affiliation:Fachbereich Chemie, Philipps-Universit?t Marburg, Marburg, Germany
Abstract:This work demonstrates how photoredox‐mediated C(sp3)?H activation through radical translocation can be combined with asymmetric catalysis. Upon irradiation with visible light, α,β‐unsaturated N‐acylpyrazoles react with N‐alkoxyphthalimides in the presence of a rhodium‐based chiral Lewis acid catalyst and the photosensitizer fac‐[Ir(ppy)3] to provide a C?C bond‐formation product with high enantioselectivity (up to 97 % ee) and, where applicable, with some diastereoselectivity (3.0:1 d.r.). Mechanistically, the synthetic strategy exploits a radical translocation (1,5‐hydrogen transfer) from an oxygen‐centered to a carbon‐centered radical with a subsequent stereocontrolled radical alkene addition.
Keywords:asymmetric catalysis  C−  H activation  photochemistry  radicals  rhodium
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号