A cascade oxidative annulation reaction of heterocyclic ketene aminals (HKAs) with internal alkynes catalyzed by [Cp*RhCl2]2 and oxidized by Cu(OAc)2·H2O was developed to efficiently synthesize highly functionalized benzo[de]chromene derivatives in good to excellent yields. The reaction proceeded by the sequential cleavage of C(sp2)-H/O-H and C(sp2)-H/C(sp2)-H bonds. These multicomponent cascade reactions were highly regioselective. In addition, all of the benzo[de]chromene products exhibited intense fluorescence emission in the solid state, and they demonstrated concentration-dependent quenching in the presence of Fe3+, indicating that these compounds could be used in the recognition of Fe3+.