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Computational Mechanistic Insights on the NO Oxidation Reaction Catalyzed by Non-Heme Biomimetic Cr-N-Tetramethylated Cyclam Complexes.

ABSTRACT: The conversion reaction of NO to NO₃^- ion catalyzed by the end-on [Cr(III)(n-TMC)(O₂)(Cl)]⁺ superoxo and side-on [Cr(IV)(n-TMC)(O₂)(Cl)]⁺ peroxo non-heme complexes (n = 12, 13, 14 and 15), which are biomimetic systems of nitric oxide dioxygenases (NODs), has been explored using a computational protocol in the framework of density functional theory. Results show that the potential energy profiles for the studied reactions lie above the reagent energies, regardless of the used catalyst. Both the O-O bond breaking in the biomimetics and the NO₃^- ion formation require low energy barriers suggesting an efficient catalytic power of the studied systems. The rate-determining step depends on ligand size.

SUBMITTER: Marino T

PROVIDER: S-EPMC6721035 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Computational Mechanistic Insights on the NO Oxidation Reaction Catalyzed by Non-Heme Biomimetic Cr-N-Tetramethylated Cyclam Complexes.

Marino Tiziana T Fortino Maria Grazia MG Russo Nino N Toscano Marirosa M Alberto Marta Erminia ME

International journal of molecular sciences 20190814 16

The conversion reaction of NO to NO3- ion catalyzed by the end-on [Cr(III)(n-TMC)(O2)(Cl)]+ superoxo and side-on [Cr(IV)(n-TMC)(O2)(Cl)]+ peroxo non-heme complexes (n = 12, 13, 14 and 15), which are biomimetic systems of nitric oxide dioxygenases (NODs), has been explored using a computational protocol in the framework of density functional theory. Results show that the potential energy profiles for the studied reactions li ...[more]

PMID: 31416223

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