An efficient two-stepsynthesis of π-expanded maleimide derivatives was reported, which proceeded via a photoinduced dehydrogenative annulation of 3,4-diphenylfuran-2(5H)-ones in EtOH at room temperature for 5 h under an argon atmosphere, followed by interaction with primary amine in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene and O2. The synthesis of highly conjugated maleimides demonstrated