Ir-Catalyzed Ortho -Selective C-H Borylation of Difluoromethyl Arenes.

The difluoromethyl group (CF 2 H) has received great attention due to its distinct properties in recent years. Herein, we report a new strategy for postmodification of difluoromethyl compounds. Ortho -selective C-H borylation of difluoromethyl arenes is achieved by a cyclometalated mesoionic carbene-Ir complex. The regioselectivity is controlled by a hydrogen bond between CF 2 H and the boryl group via the outer-sphere direction.