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Substrate and metal control of barrier heights for oxo transfer to Mo and W bis-dithiolene sites.

ABSTRACT: Reaction coordinates for oxo transfer from the substrates Me(3)NO, Me(2)SO, and Me(3)PO to the biologically relevant Mo(IV) bis-dithiolene complex [Mo(OMe)(mdt)(2)](-) where mdt = 1,2-dimethyl-ethene-1,2-dithiolate(2-), and from Me(2)SO to the analogous W(IV) complex, have been calculated using density functional theory. In each case, the reaction first proceeds through a transition state (TS1) to an intermediate with substrate weakly bound, followed by a second transition state (TS2) around which breaking of the substrate X-O bond begins. By analyzing the energetic contributions to each barrier, it is shown that the nature of the substrate and metal determines which transition state controls the rate-determining step of the reaction.

SUBMITTER: Tenderholt AL

PROVIDER: S-EPMC3319056 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Substrate and metal control of barrier heights for oxo transfer to Mo and W bis-dithiolene sites.

Tenderholt Adam L AL Hodgson Keith O KO Hedman Britt B Holm Richard H RH Solomon Edward I EI

Inorganic chemistry 20120228 6

Reaction coordinates for oxo transfer from the substrates Me(3)NO, Me(2)SO, and Me(3)PO to the biologically relevant Mo(IV) bis-dithiolene complex [Mo(OMe)(mdt)(2)](-) where mdt = 1,2-dimethyl-ethene-1,2-dithiolate(2-), and from Me(2)SO to the analogous W(IV) complex, have been calculated using density functional theory. In each case, the reaction first proceeds through a transition state (TS1) to an intermediate with substrate weakly bound, followed by a second transition state (TS2) around whi ...[more]

PMID: 22372518

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Dataset Information

Substrate and metal control of barrier heights for oxo transfer to Mo and W bis-dithiolene sites.

Publications

Substrate and metal control of barrier heights for oxo transfer to Mo and W bis-dithiolene sites.

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