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Dramatically accelerated selective oxygen-atom transfer by a nonheme iron(IV)-oxo complex: tuning of the first and second coordination spheres.

ABSTRACT: The new ligand N3Py(amide)SR and its Fe(II) complex [Fe(II)(N3Py(amide)SR)](BF4)2 (1) are described. Reaction of 1 with PhIO at -40 °C gives metastable [Fe(IV)(O)(N3Py(amide)SR)](2+) (2), containing a sulfide ligand and a single amide H-bond donor in proximity to the terminal oxo group. Direct evidence for H-bonding is seen in a structural analogue, [Fe(II)(Cl)(N3Py(amide)SR)](BF4)2 (3). Complex 2 exhibits rapid O-atom transfer (OAT) toward external sulfide substrates, but no intramolecular OAT. However, direct S-oxygenation does occur in the reaction of 1 with mCPBA, yielding sulfoxide-ligated [Fe(II)(N3Py(amide)S(O)R)](BF4)2 (4). Catalytic OAT with 1 was also observed.

SUBMITTER: Widger LR

PROVIDER: S-EPMC4004223 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Dramatically accelerated selective oxygen-atom transfer by a nonheme iron(IV)-oxo complex: tuning of the first and second coordination spheres.

Widger Leland R LR Davies Casey G CG Yang Tzuhsiung T Siegler Maxime A MA Troeppner Oliver O Jameson Guy N L GN Ivanović-Burmazović Ivana I Goldberg David P DP

Journal of the American Chemical Society 20140210 7

The new ligand N3Py(amide)SR and its Fe(II) complex [Fe(II)(N3Py(amide)SR)](BF4)2 (1) are described. Reaction of 1 with PhIO at -40 °C gives metastable [Fe(IV)(O)(N3Py(amide)SR)](2+) (2), containing a sulfide ligand and a single amide H-bond donor in proximity to the terminal oxo group. Direct evidence for H-bonding is seen in a structural analogue, [Fe(II)(Cl)(N3Py(amide)SR)](BF4)2 (3). Complex 2 exhibits rapid O-atom transfer (OAT) toward external sulfide substrates, but no intramolecular OAT. ...[more]

PMID: 24471779

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