Metal‐Free, Oxidative Condensation of Heteroaryl‐ and Aryl Carbaldehydes towards Functionalized Carbonitriles.

Functionalization of pyridines with the carbonitrile group for advanced cyclization reactions routinely incorporates metals, toxic oxidants, and cyanide reagents, often in linear synthetic sequences. Motivated by the strategic need of a heteroaryl carbonitrile synthon for further elaboration, we disclose an efficient, metal‐free, one‐pot reaction sequence that uses ammonium acetate as the nitrogen source and bis‐acetoxyiodobenzene as the oxidant with low loadings. The developed method tolerates a diverse substrate scope including heteroaryl, aryl, and alkyl substrates with similar efficiency and expands the practitioner's reaction. Method development, optimization, substrate scope, preliminary mechanistic observations, competition experiments, and a scale up reaction are delineated herein. [ABSTRACT FROM AUTHOR]