Ag(i)-catalyzed intramolecular transannulation of enynone tethered donor-acceptor cyclopropanes: a new synthesis of 2,3-dihydronaphtho[1,2-b]furans

An efficient AgOTf catalyzed tandem intramolecular transannulation of ((2-alkynyl)aryl)cyclopropyl ketones leading to the 2,3-dihydronaphtho[1,2-b]furans has been developed. The reaction features a regioselective alkyne hydration, cyclopropylketone-2,3-dyhydrofuran rearrangement, and benzannulation. The methodology gives direct access to the tricyclic core structure of biologically important 2,3-dihydronaphtho[1,2-b]furan natural products.