Photoredox-Mediated C–N Bond Cleavage Enables Synthesis of Tetra -Substituted Olefins via Reductive Radical-Polar Crossover

Synthesizing all-carbon tetra-substituted olefins is challenging due to steric hindrance. Herein, we report a concise photoinduced radical aryl migration strategy for accessing these valuable structures with excellent stereoselectivity under mild conditions. This method is compatible with various carboxylic acids, including amino acids, dipeptides, and alkyl carboxylic acids, and propiolamides with electron-rich or electron-deficient aryl groups. Mechanistic studies reveal a reductive radical-polar crossover (RPC) pathway involving C-N bond cleavage via a synergistic single-electron transfer (SET) mechanism. The obtained tetra-substituted olefins exhibit significant aggregation-induced emission (AIE) effects, complementing research and applications in organic synthesis and advanced materials.