Sequential C–H Aroylation and Formal [4 + 2] Cycloaddition of Naphthalenes with Aroylfluorides and Styrenes

While single-electron transfer (SET) and energy transfer (EnT) processes have each made significant contributions to photochemical catalysis, their combination in an SET–EnT sequence remains underexplored. Here, we report a sequential activation strategy that merges SET and EnT catalysis to achieve the dearomatization of naphthalene derivatives through sequential C–H activation and [4 + 2] cycloaddition, enabling the efficient construction of bridged polycyclic frameworks. Key to this approach is an SET-mediated, NHC-catalyzed prefunctionalization of the naphthalene ring, which modulates its triplet energy, thereby facilitating selective EnT-driven cycloaddition with alkenes. This strategy provides precise control over reactivity, expands the scope of visible-light-mediated catalysis, and offers a robust platform for the synthesis of complex three dimensional (3D) molecular architectures from simple precursors.