Ni(II) catalyzed bromination of aryl C-H bonds

摘要

Bromination of unactivated aromatic C-H bonds without directing and/or chelating groups was achieved by employing an air stable N-heterocyclic Ni(II) complex. PhI(OAC)(2) and N-bromosuccinimide have been used as the oxidizing agent and the bromine source, respectively. Yields for bromination are as high as >99%, especially in presence of electron-withdrawing groups like -NO2 and -CF3. This is a rare report on C-H bond activation with Ni(II) where, instead of homo C-C coupling, reductive elimination to form C-halogen could be achieved. (C) 2014 Elsevier B.V. All rights reserved.