Cu(II)-mediated annulation of 4-hydroxycoumarins with propargyl carbonates: Facile access to furo[3,2-c]coumarin scaffold

Abstract

An efficient and facile approach to furo[3,2-c]coumarin was developed from 4-hydroxycoumarins and propargyl carbonates. This protocol underwent [3 + 2] annulation process smoothly under mild reaction conditions to afford the desired products in moderate to excellent yields. A plausible mechanism was proposed. The products obtained could be readily converted into potentially bioactive furocoumarin derivatives.