Cyanation of N-acylhydrazones using trimethylsilylcyanide (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 Brønstedbase