Covalent Organic Frameworks as a Versatile Platform for Iron‐Catalyzed sp3 C−H Activation and Cross‐Coupling via Decarboxylative Oxidation

Abstract This work demonstrates the oxidative cross‐coupling of cinnamic acids with toluene using FeCl 3 immobilized on a covalent organic framework (COF) pore wall, resulting in the synthesis of 1,3‐arylpropene derivatives. This iron‐based heterogeneous catalytic system affords the desired products in moderate yields ranging from 51 % to 65 %. Investigations using COFs with varying pore sizes indicate that larger pores facilitate the reaction, suggesting a spatial requirement for this transformation within the catalyst. The correlation between pore size and reaction efficiency provides insights into developing tailored catalysts to match the spatial requirements of the transformation. This version emphasizes the novelty of the study and the synthesis of 1,3‐arylpropene derivatives. It also clarifies that the iron‐based heterogeneous catalytic system is responsible for the reaction. Additionally, it provides a more detailed explanation of the findings regarding pore size and spatial requirements.