Concentrated solar radiation-assisted one-pot/multicomponent synthesis of pyranopyrazole derivatives under neat condition

Concentrated solar radiation (CSR)-assisted synthesis of pyranopyrazole derivatives under solvent and catalyst-free condition has been reported in the present protocol. One-pot multicomponent synthesis from aromatic/heteroaldehyde, ethyl acetoacetate, malononitrile, and hydrazine hydrate leads to the final desired compounds in a good yield. This operationally simple methodology has several advantages such as green and clean reaction profile, simple workup and purification procedures, extremely short reaction time, atom efficiency, and being economical. The current energy-efficient method saves almost 98% of energy as compared to the conventional method.