Electrophotochemical Oxidation and Carbene Transfer Cascade Reaction for the Synthesis of Cyclopropane Compounds

Electrophotochemical synthesis is emerging as a powerful and sustainable methodology in organic synthesis. This work describes the successful integration of photochemical and electrosynthesis to achieve an oxidation and carbene transfer cascade reaction for the synthesis of cyclopropane compounds. This strategy operates without stoichiometric oxidants or reductants, enabling efficient and highly selective redox transformations under mild conditions. Key to this process is the in situ electrochemical generation of diazo compounds from stable hydrazones, which subsequently undergo photolytic carbene formation and cyclopropanation with olefin derivatives in a single pot. This approach effectively mitigates the handling and stability issues associated with isolated diazo compounds. The reaction system was optimized, identifying acetonitrile as the optimal solvent with graphite and platinum electrodes in the presence of NH 4 OAc and KI, achieving high yields of various cyclopropane derivatives. This electrophotochemical method provides a practical, metal‐oxidant‐free, and environmentally friendly alternative for accessing valuable cyclopropane architectures.