Annulative coupling of dicoumarols and β-ketosulfoxonium ylides: access to dihydrofuran-fused coumarins
Abstract
A reagent- and catalyst-free one-pot cascade strategy has been developed for the efficient synthesis of dihydrofuran-fused coumarins (DHFCs) from β-ketosulfoxonium ylides and dicoumarol derivatives. This eco-friendly method involves sequential intermolecular 1,4-conjugate addition and intramolecular O-cyclization, efficiently forming C–C and C–O bonds. It exhibits broad substrate scope, good to high yields, and practical scalability with potential for bioactive molecule derivatization.