Cyanation of N‐Acylhydrazones with Trimethylsilyl Cyanide Promoted by a Brønsted Base and a Lewis Acid

Cyanation of N‐acylhydrazones using trimethylsilyl cyanide (TMSCN) proceeded well in the presence of an amine to afford the corresponding α‐hydrazinonitriles in high yields. For less reactive substrates, the combined use of an amine and a catalytic amount of scandium triflate [Sc(OTf)₃] was effective to promote the reactions. The mechanistic study suggested that the amine worked as a Brønsted base.