Transformation of Benzaldehydes to Benzonitriles via Cyanophosphates without One-carbon Homologation

Abstract

Transformation of benzaldehydes to benzonitriles via cyanophosphates (CPs) with tetrabutylammonium azide (Bu4N·N3) was found, affording a range of benzonitriles in modest-to-high yields. As the CN-carbon of benzonitriles arises from the formyl-carbon of benzaldehydes, this is a new type of CP-reaction, distinctly different from the past one-carbon nitrile homologation. In contrast, reaction of ketone- or aliphatic aldehyde-CPs with Bu4N·N3 occurred mono-deethylaton, forming tetrabutylammonium salts.