An Insight into Nitromethane as an Organic Nitrile Alternative Source towards the Synthesis of Aryl Nitriles

Directed by an unusual in situ reduction of CuII, our protocol is a simple CuI‐mediated synthesis of aryl nitriles, with inexpensive and readily available nitromethane as the cyanating source, in moderate to good yields. Exhibiting a wide substrate scope, the method involves simple reaction conditions, is additive free with low catalyst loading. The plausible mechanism of cyanation of aryl halides is elucidated by a congregation of three cycles, namely the in situ reduction of CuII species by nitromethane, generation of HCN species from nitromethane and a regular organometallic pathway which releases the nitrile derivative. The detail of the mechanism of generation of CN– from nitromethane is computationally validated. Our protocol holds the distinction of involving a rarely encountered CuI catalytic species as well as facile in situ generation of nucleophilic CN– to yield synthetically useful aromatic nitriles. An experimental and computational study into the synthesis of aryl nitriles with nitromethane as an organic and non‐toxic alternative of traditional cyanating sources is presented. The mechanistic pathway of cyanation is the highlight of the current study.