Catalyst-free Diazo Cross-coupling to Access Useful 3(2)-furanone Derivatives

Catalyst-free synthesis of 3(2)-furanone derivatives has been achieved from metal-free cross-coupling of α-diazo ester and α-aryldiazo ketones. This reaction sequence comprises a prior Wolff rearrangement of α-aryldiazo ketones to 2-arylketenes, which are trapped with α-diazo esters to form cyclopropanones before undergoing oxa-Nazarov cyclization.