Using Nature’s Blueprint Porous Organic Polymeric Nanotrap Enabling the Interfacial Activation of Hosted Amine & CO2

Abstract

Porous organic polymers (POPs) constructed via Schiff-base chemistry have garnered increasing attention as advanced materials for heterogeneous catalysis, owing to their inherent structural tunability, high surface area, and chemical stability. In this study, we report the rational design and synthesis of a histidine-functionalized porous organic polymer, His-POP, via a one-pot Schiff-base condensation, followed by post-synthetic metalation with ZnCl2 to afford a zinc-coordinated framework, Zn@His-POP. Nitrogen sorption analysis revealed a high BET surface area of 900.5 m2/g for His-POP, which decreased to 452.6 m2/g upon zinc incorporation, consistent with partial pore occupation by Zn metal species. The metalated polymer was employed as an efficient and recyclable catalyst for the N-formylation of amines using phenylsilane as a mild hydride donor, which exhibited excellent catalytic activity across a broad range of substrates under mild conditions. The enhanced catalytic performance is attributed to the cooperative effect between the Zn(II) centres and the histidine-functionalized microporous environment, which facilitates substrate activation and product release. An insightful investigation using density functional theory (DFT) provides evidences on CO2 adsorption mechanism on the Zn@His-POP, as well as the mechanism for the N-formylation reaction. This work underscores the potential of bioinspired, metal-functionalized POPs as robust platforms for sustainable catalysis and paves the way for the development of next-generation nanozyme-mimetic materials.