Simple Synthesis of Some Novel Polyfunctionally Derivatives of 2H-Coumarin-2-One.

Compound (2) was prepared from the reaction of ethyl-2-oxo-2H-coumarin-3-carboxylate (1) with ethylcyanoacetate in ethanol containing a catalytic amount of piperidine as catalyst. Compound (2) is the key intermediate for the synthesis of several series of new compounds such as ((pyrimidine, tetrazine, piperidine, oxazepine)-2H-coumarin-2-one derivatives by reaction with selected reagents such as urea, cyanoacetamide, cyanoacetohydrazide, orthoaminophenol and 5-aminotriazole.