An Eco-friendly Catalytic System for One-pot Multicomponent Synthesis of Diverse and Densely Functionalized Pyranopyrazole and Benzochromene Derivatives

An external base-free, efficient, cost-effective, and environmentally benign protocol has been developed for the one-pot multicomponent synthesis of highly functionalized pyranopyrazoles and benzochromenes using water extract of Agave americana (century plant) leaf ash, a waste-derived catalyst, at room temperature. Mild reaction conditions, high yield, easy isolation of products, eco-friendly standards, and no chromatographic separation are the salient features of this protocol.