Zinc-promoted reactions. 9. The fate of the cyano group in the reduction of simple cyanoketones and N-cyanoamines

Abstract The Zn/AcOH reduction of 1 leads only to the carbonyl reduction, while C-decyanation occurs in the case of 2 . The mechanism of the latter reaction is discussed. The N-decyanation of N-cyanoamines 3 and 4 involves an ionic mechanism, leading to N-acyl derivatives and isocyanic acid, the latter compound being ultimately reduced to formic acid.