Cine Substitution of Arenes Using the Aryl Carbamate as a Removable Directing Group

An efficient and controlled means to achieve a rare cine substitution of arenes is reported. The methodology relies on the strategic use of aryl O-carbamates as readily removable directing groups for arene functionallzation. The removal of aryl carbamates is achieved by employing an airstable Ni(II) precatalyst, along with an inexpensive reducing agent, to give synthetically useful yields across a range of substrates. The net cine substitution process offers a new strategy for analogue synthesis, which complements the well-established logic for achieving arene functionalization by ipso substitution.