A Green and Efficient NH4OAc-catalyzed Synthesis of 2-Hydroxy-3-(arylmethyl)(4-hydroxy-2-oxo-2,5-dihydrofuran-3-yl)-1,4-naphthoquinones

Abstract

The green and efficient approach for synthesis of 2-hydroxy-3-(arylmethyl)(4-hydroxy-2-oxo-2,5-dihydrofuran-3-yl)-1,4-naphthoquinones starting from 2-hydroxy-1,4-naphthoquinone, tetronic acid, and aromatic aldehydes was developed. These reactions were carried out in ethanol under microwave irradiation in the presence of ammonium acetate as catalyst. These multicomponent domino reactions presumably occur via NH4OAc-catalyzed Mannich reaction - Michael addition - hydration - tautomerism - elimination sequence of reactions.