Tuning the oxidation activity of alcohols via hydrogen-bond interactions

Abstract

Abstract Weak interactions, such as hydrogen bonds, are crucial in enzyme catalysis. Here, we develop AuPd alloy nanoparticle catalysts encapsulated by a porous organic framework shell that mimics the outer coordination sphere of an enzyme. Various hydrogen bond acceptors (C=O, S=O, and N-O groups) were imparted in the shell. Concentration-dependent 1H-NMR, IGC measurements, and DFT calculations underscore that the hydrogen bond strength between the catalyst acceptor groups and alcohol follows the order of C=O<S=O<N-O. Benzyl alcohol oxidation rate vs. the hydrogen bond acceptor strength follows a volcano behavior, reminiscent of Sabatier's principle. The performance variation among catalysts is attributed to the adsorption strength of the substrate. The proposed bio-inspired design principle expands the scope of encapsulated catalysts, enabling fine regulation of catalytic activity through precise microenvironment control via weak interactions with substrates.