Copper/silver co-mediated three-component bicyclization for accessing indeno[1,2- c]azepine-3,6-diones

Chem Commun (Camb). 2021 Aug 10;57(64):7966-7969. doi: 10.1039/d1cc02973h.

Abstract

A new copper/silver-co-mediated three-component bicyclization of benzene-linked 1,6-enynes with ICF2CO2Et with TMSN3 was reported, and used to produce a wide range of hitherto unreported difluorinated tetrahydroindeno[1,2-c]azepine-3,6-diones with moderate to good yields. The mechanistic pathway consists of radical-induced 1,6-addition-cyclization, oxidative addition, reductive elimination, nitrene insertion and N-O cleavage, resulting in continuous multiple bond-forming events including C-C and C-N bonds to build up a 6/5/7 tricyclic framework.