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N-Heterocyclic Carbene Modified Palladium Catalysts for the Direct Synthesis of Hydrogen Peroxide.

ABSTRACT: Heterogeneous palladium catalysts modified by N-heterocyclic carbenes (NHCs) are shown to be highly effective toward the direct synthesis of hydrogen peroxide (H₂O₂), in the absence of the promoters which are typically required to enhance both activity and selectivity. Catalytic evaluation in a batch regime demonstrated that through careful selection of the N-substituent of the NHC it is possible to greatly enhance catalytic performance when compared to the unmodified analogue and reach concentrations of H₂O₂ rivaling that obtained by state-of-the-art catalysts. The enhanced performance of the modified catalyst, which is retained upon reuse, is attributed to the ability of the NHC to electronically modify Pd speciation.

SUBMITTER: Lewis RJ

PROVIDER: S-EPMC9449981 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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N-Heterocyclic Carbene Modified Palladium Catalysts for the Direct Synthesis of Hydrogen Peroxide.

Lewis Richard J RJ Koy Maximilian M Macino Margherita M Das Mowpriya M Carter James H JH Morgan David J DJ Davies Thomas E TE Ernst Johannes B JB Freakley Simon J SJ Glorius Frank F Hutchings Graham J GJ

Journal of the American Chemical Society 20220817 34

Heterogeneous palladium catalysts modified by N-heterocyclic carbenes (NHCs) are shown to be highly effective toward the direct synthesis of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), in the absence of the promoters which are typically required to enhance both activity and selectivity. Catalytic evaluation in a batch regime demonstrated that through careful selection of the N-substituent of the NHC it is possible to greatly enhance catalytic performance when compared to the unmodified analo ...[more]

PMID: 35976628

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