Recent Advance in Photo‐/Electrocatalytic Difunctionalization of Alkenes <i>via</i> Radical‐Polar Crossover ^†

Comprehensive Summary The catalytic difunctionalization of alkenes offers an efficient and straightforward approach to incorporating two functional groups across a double bond for increasing molecular complexity and has found widespread application in organic synthesis. Among them, photo‐/electrocatalytic difunctionalization of alkenes based on the radical‐polar crossover strategy has gained increasing attention. This approach not only aligns with the principles of green and sustainable chemistry but also uniquely merges both radical and ionic modes of reactivity, overcoming the inherent limitations of conventional methodologies. This review summarizes the innovative progress in photo‐/electrocatalytic difunctionalization of alkenes over the last decade, which is focused on the transformations via oxidative radical‐polar crossover (ORPC) or reductive radical‐polar crossover (RRPC) as the key step and particular emphasizes on the selection of functionalized polar adducts. Key Scientists