Temperature‐Dependent Regiodivergent Synthesis of Functionalized Maleimides and Itaconimides via <i>in‐situ</i> Generated Pyridinium Ylide

Abstract We report a temperature‐dependent regiodivergent synthetic strategy for the construction of functionalized maleimides and itaconimides using in‐situ generated pyridinium ylides. This approach enables efficient access to both regioisomeric products under mild and straightforward reaction conditions. A variety of pyridinium salts with different aromatic and alkyl groups were successfully used with N ‐aryl and N ‐alkyl succinimides demonstrating broad substrate compatibility. The practicality and scalability of this methodology were confirmed through scale‐up experiments, which maintained high yields and reproducibility.