Rhodium(iii)-catalyzed C–H/C–F activation sequence: expedient and divergent synthesis of 2-benzylated indoles and 2,2′-bis(indolyl)methanes†
Abstract
Herein, an original and divergent synthetic method for fluorinated 2-benzylated indoles and 2,2′-bis(indolyl)methanes has been established for the first time via Rh(III)-catalyzed C–H/C–F activation of arenes employing 3,3-difluoro-2-exo-methylidene indolines as novel cross-coupling partners. This redox-neutral protocol exhibited a broad substrate scope (30 examples, up to 97% yield) and high functional-group compatibility. Gram-scale and mechanistic studies were also performed.