Photocatalytic Reaction of Diazo Compounds with Aldehydes

Abstract Photocatalytic reactions of diazoacetates with aldehydes led to α‐alkylated carbonyl compounds instead of the expected cyclopropane derivatives. The reaction requires a dual catalytic system – photocatalysis merged with enamine‐iminium catalysis. NMR, EPR, UV/Vis, and ESI‐MS analyses provided sufficient data to corroborate the proposed radical mechanism – enamine catalysis merged with photocatalysis. magnified image