Unripe grape juice (verjuice) as a natural catalyst was successfully applied to perform the one-pot reaction of aryl aldehydes, malononitrile, hydrazine hydrate and ethyl acetoacetate to synthesize pyranopyrazole derivatives in aqueous ethanol at room temperature in excellent yields. Furthermore, unripe grape juice catalyzed one-pot synthesis of hexahydroquinoline-3-carboxamide derivatives by the four-component reaction of arylaldehydes, dimedone, […]
