Rhodium‐Catalysed [4+2] Annulation of Aromatic Oximes with Terminal Alkenes by C−H/N−O Functionalization towards 3,4‐Dihydroisoquinolines
作者:Xu Zhang、Xuan‐Hui Ouyang、Yang Li、Bo Chen、Jin‐Heng Li
DOI:10.1002/adsc.201900922
日期:2019.11.5
Rhodium (Rh)‐catalysed [4+2] annulation of aromatic oximes with common terminal alkenes for the synthesis of 3,4‐dihydroisoquinolines is presented. Through the cooperation of a Rh(III) catalyst and a catalytic amount of K2HPO4 base, the reaction enables the formation of two new bonds, a C(sp2)−C(sp3) bond and a C(sp3)−N bond, in a single reaction via functionalization of both the C−H and N−O bonds
Thanks to CHactivation: 3‐Aryl‐3,4‐dihydroisoquinolines (2) are synthesized from bromobenzenes (1) by a sequence comprising a C(sp3)Hactivation, a Curtius rearrangement, and a tandem electrocyclic ring‐opening/6π electrocyclization. This method is applied to the synthesis of various isoquinoline‐containing molecules, including the tetrahydroprotoberberine alkaloid coralydine.