Synthesis of 2-Benzazepines from Benzylamines and MBH Adducts Under Rhodium(III) Catalysis via C(sp2)–H Functionalization

The rhodium(III)-catalyzed cross-coupling reaction between commercially available benzylamines and Morita–Baylis–Hillman (MBH) adducts is described. This protocol provides a facile access to various 2-benzazepine derivatives via the C(sp2)–H activation of N-allylated benzylamines and subsequent intramolecular olefin insertion followed by N-allylation reaction. A range of substrates has been used, and a high level of chemoselectivity as well as functional group tolerance was observed. To gain mechanistic insight of this transformation, DFT calculations were also performed.