Imidazolium‐Derived Porous Organic Polymer as Robust Platform for Rhodium‐Catalyzed N ₂ O Hydrogenation and Alcohol Oxygenation

Abstract

Abstract The catalytic conversion of nitrous oxide, a potent greenhouse gas and ozone‐depleting substance, offers a promising strategy for mitigating emissions but requires efficient catalysts that operate under mild conditions. Here, a porous organic polymer was designed as a functional platform for accommodating built‐in catalytic sites. The polymer incorporates rigid 1,3‐dimethylbenzimidazolium iodide units as stable precursors to N‐heterocyclic carbenes, providing suitable coordination sites to molecular catalysts, high surface area, and chemical robustness. Deprotonating these precursors generates free carbene ligands that effectively coordinate and immobilize a rhodium bis(olefin) amine complex. Upon activation with base, the air stable immobilized complex forms reactive metal‐ligand cooperative Rh–N sites that convert nitrous oxide to nitrogen via in situ generated rhodium(I) hydride species. Exceptional performance was observed during catalytic hydrogenation of nitrous oxide under heterogeneous solid–liquid–gas conditions in batch reactors (using tetrahydrofuran or water) and under solid–gas conditions. Furthermore, the catalyst enabled the dehydrogenative coupling of primary alcohols (methanol, ethanol and benzyl alcohol) with nitrous oxide as a hydrogen acceptor, achieving turnover numbers that surpass all previously reported catalysts. These findings demonstrate the potential of porous organic polymer–metal complexes as robust, recyclable and efficient catalysts.