Reaction of ethyl cyanoacetate with benzal-4-acetylanilines: An unexpected result

Abstract

Reaction of ethyl cyanoacetate with benzal-4-acetylanilines 1a-10a, the compounds containing both azomethine and ketone linkages, in equimolar ratio, in the presence of pyridine yields solid products, which have been characterized as ethyl benzalcyanoacetate and its derivatives 1b-10b on the basis of elemental analysis and spectral studies. The reaction of 1a-10a with two moles of ethyl cyanoacetate also results in the formation of the same products 1b-10b, by an unexpected attack of ethyl cyanoacetate on azomethine linkage only rather than on both the reactive centres i.e. carbon-nitrogen double bond and carbon-oxygen double bond.