Unlocking the Free Radical Evolution for Directed Conversion of Furoic Acid to 2,5‐Furandicarboxylic Acid Over Lattice‐Distorted MnO <i>x</i>

Abstract

Abstract Developing the efficient C─H bond activation carboxylation processes for furoic acid (FA) represents a critical technological challenge in achieving atom‐economical synthesis of 2,5‐furandicarboxylic acid (FDCA). Despite notable advancements in this field, the inherent contradiction between the high reactivity of furan rings and the chemical inertness of C─H bonds poses substantial technical bottleneck for achieving controllable C─H carboxylation under mild conditions. Herein, we report a high lattice‐distorted MnOx catalyst with surface trench‐like structures, wherein the Mn δ+ ‐O V ‐conjugated configurations and electron‐rich Mn 2+ cooperatively drive FA dehydrogenation and carbon radical reduction, inducing the free radical evolution process (FA→carbon‐centered FA radical→FA carbanion), then coupled with solvent‐polarized CO 2 to accelerate the carboxylation process. This approach achieved an FDCA selectivity of 95.82% under mild reaction conditions (≤390 K), providing novel insights into mild activation and conversion of biomass‐derived inert chemical bonds.