A Simple Efficient Procedure for the Synthesis of Benzopyrano[2,3‐c]pyrazoles

A one-step procedure is proposed for synthesizing 2-acyl benzopyrano[2,3-c]pyrazoles and 2-aryl benzopyrano[2,3-c]pyrazoles. The method is based on the condensation of 2-iminocoumarin-3-carbonitriles with hydrazides and hydrazines in acid as catalysts. A mechanism of reaction is proposed. All prepared compounds are identified by FTIR, 1H NMR, 13C NMR, mass spectroscopy, and elemental analysis.