Condensation of aromatic aldehydes with ethoxycarbonylacetohydrazide and cyanoacetohydrazide
Abstract
Hydrazones (1a and b) formed from aromatic aldehydes by condensation with ethoxycarbonylacetohydrazide and cyanoacetohydrazide, respectively, undergo Knoevenagel condensations to yield either mono-(2) or di-adducts (3). With salicylaldehyde, however, only coumarin derivatives are produced.