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

Abstract

The transformation of benzaldehydes into benzonitriles via cyanophosphates (CPs) with tetrabutylammonium azide (Bu₄N·N₃) was found to afford 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, the reaction of ketone- or aliphatic aldehyde-CPs with Bu₄N·N₃ resulted in mono-deethylaton forming tetrabutylammonium salts.

Key words

cyanophosphate - tetrabutylammonium azide - mono-deethylaton - benzonitrile - tetrabutylammonium salt

• References

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