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Formation of a room temperature stable Fe(V)(O) complex: reactivity toward unactivated C-H bonds.

ABSTRACT: An Fe(V)(O) complex has been synthesized from equimolar solutions of (Et4N)2[Fe(III)(Cl)(biuret-amide)] and mCPBA in CH3CN at room temperature. The Fe(V)(O) complex has been characterized by UV-vis, EPR, Mössbauer, and HRMS and shown to be capable of oxidizing a series of alkanes having C-H bond dissociation energies ranging from 99.3 kcal mol(-1) (cyclohexane) to 84.5 kcal mol(-1) (cumene). Linearity in the Bell-Evans-Polayni graph and the finding of a large kinetic isotope effect suggest that hydrogen abstraction is engaged the rate-determining step.

SUBMITTER: Ghosh M

PROVIDER: S-EPMC5338741 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Formation of a room temperature stable Fe(V)(O) complex: reactivity toward unactivated C-H bonds.

Ghosh Munmun M Singh Kundan K KK Panda Chakadola C Weitz Andrew A Hendrich Michael P MP Collins Terrence J TJ Dhar Basab B BB Sen Gupta Sayam S

Journal of the American Chemical Society 20140116 27

An Fe(V)(O) complex has been synthesized from equimolar solutions of (Et4N)2[Fe(III)(Cl)(biuret-amide)] and mCPBA in CH3CN at room temperature. The Fe(V)(O) complex has been characterized by UV-vis, EPR, Mössbauer, and HRMS and shown to be capable of oxidizing a series of alkanes having C-H bond dissociation energies ranging from 99.3 kcal mol(-1) (cyclohexane) to 84.5 kcal mol(-1) (cumene). Linearity in the Bell-Evans-Polayni graph and the finding of a large kinetic isotope effect suggest that ...[more]

PMID: 24387595

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