Substrate Self-Excitation Reaction Driven by Visible Light To Access Benzo[ b ]fluorene Derivatives

A photosensitizer-free methodology has been developed for the synthesis of benzo[b]fluorene derivatives via visible-light-driven substrate self-excitation, using light as the sole energy source. The mechanism was mechanistically investigated, including control experiments, optical experiments, deuterium labeling experiments, and DFT calculations. A series of extended π-conjugated systems derived from readily available indanones, aldehydes, and malononitriles were converted into benzo[b]fluorene derivatives.