Mg-Al Hydrotalcite as a First Heterogeneous Basic Catalyst for the Synthesis of 4H-Pyrano[2,3-c]pyrazoles Through a Four-Component Reaction

[image omitted] Mg/Al hydrotalcite acts as an efficient heterogeneous basic catalyst for the synthesis of 4H-pyrano[2,3-c]pyrazoles via a multicomponent reaction of aromatic hydrazine hydrate, ethyl acetoacetate, aldehydes, and malononitrile in ethanol at ambient temperature. The hydrotalcite catalyst was easily separated from the reaction mixture and can be reused.