Rhodium catalyzed cyanide-free cyanation of aryl halide by using formamide as a cyanide source

This work reports rhodium–xantphos as a new catalytic system for cyanide-free cyanation of aryl halides to aryl nitriles. The reaction takes place in the presence of phosphorous oxychloride as an acid and formamide as a cyanide source cum solvent. The developed protocol avoids the use of highly toxic metal cyanides. This methodology is a simple, single step reaction involving formamide as a safe and nontoxic source of cyanation. A variety of aryl iodides/bromides were well tolerated under optimized reaction conditions providing moderate to excellent yield of corresponding cyanides.