Base-promoted multicomponent synthesis of 1,2,4-triazole-based hybrids from 1,3-diones, β-nitrostyrenes, and hydrazones.

Herein, we report a metal-free, base-promoted route for the synthesis of hybrid molecular scaffolds in which various 1,3-diones and 1,2,4-triazoles are linked by a benzyl bridge. This three-component, one-pot reaction was accomplished by first treating 4-hydroxycoumarin, -β-nitrostyrene, and aldehyde hydrazone in the presence of sodium carbonate. Further, this protocol was successfully expanded to other 1,3-diones, such as dimedone and 4-hydroxy-2-quinolone. A broad substrate scope, mild reaction conditions, and the metal and ligand/additive-free approach are the prominent features of this strategy.