Heterocyclic imines and amines. Part XI. Reactions of o-cyanocinnamonitriles and related compounds with nitrogen bases

Abstract

Hydroxylamine adds under mild conditions to both nitrile groups of the o-cyanocinnamonitriles to give amidoximes whereas piperidine and ammonia add to the side-chain double bond to give β-amino-nitriles. Hydrazine adds at the β-position, and this is followed by cyclisation onto the o-substituent and substitution of reactive functional groups to yield 2-amino-3-cyanomethylisoindolin-1-one hydrazone. A similar reaction is observed with o-carbamoyl-trans-cinnamamide in addition to the base-catalysed cyclisation to a 2-unsubstituted isoindolinone. Under more vigorous conditions o-cyano-cis-cinnamamide gives a phthalazine, evidently through dehydrogenation of the intermediate β-adduct.

Light absorptions and ¹H n.m.r. results provide structural evidence. Amidoxime-I and -II bands in the i.r. are recognised.