Switching from 2-pyridination to difluoromethylation: ligand-enabled nickel-catalyzed reductive difluoromethylation of aryl iodides with difluoromethyl 2-pyridyl sulfone

The divergent reductive cross-coupling with an ambident electrophile is rare. Previously, we demonstrated a nickel-catalyzed reductive 2-pyridination of aryl iodides with difluoromethyl 2-pyridyl sulfone (2-PySO₂CF₂H) via selective C(sp²)–S bond cleavage of the sulfone by using a phosphine ligand. In this communication, we report a novel nickel-catalyzed reductive coupling of aryl iodides and 2-PySO₂CF₂H reagent, which constitutes a new method for aromatic difluoromethylation. The use of a tridentate terpyridine ligand is pivotal for the selective C(sp³)–S bond cleavage of the sulfone. This method employs readily available nickel catalyst and 2-PySO₂CF₂H as the difluoromethylation reagent, providing a facile access to difluoromethylarenes under mild reaction conditions without pre-generation of arylmetal reagents.