One-pot transition-metal-free cascade synthesis of thieno[2,3-c]coumarins from chromones

Abstract

A one-pot transition-metal-free, base-mediated synthesis of a novel series of functionalized thieno[2,3-c]coumarins via a cascade reaction from chromones has been developed. This cascade reaction involves a Michael addition–Knoevenagel condensation–intramolecular cyclization. This transformation proceeds under mild conditions and gives various thieno[2,3-c]coumarins in good-to-excellent yields. The methodology is tolerant of a wide range of functional groups and applicable to library synthesis.