Direct and Site-Selective C–H Cyanation of (Hetero)arenes by a Nontoxic Cyano Source

Direct C-H cyanation of arenes and heteroarenes is herein reported using a nontoxic cyano source with high regioselectivity. CuI serves as an essential multifunctional catalyst, which promotes the in situ generation of Cu-CN and aryl iodides and the subsequent cross-coupling of these two intermediates to yield aryl nitrile products. The new strategy of C-H cyanation, good regioselectivity, and the use of a nontoxic cyano source together represents a significant advancement in cyanation chemistry.