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Secondary coordination sphere influence on the reactivity of nonheme iron(II) complexes: an experimental and DFT approach.

ABSTRACT: The new biomimetic ligands N4Py(2Ph) (1) and N4Py(2Ph,amide) (2) were synthesized and yield the iron(II) complexes [Fe(II)(N4Py(2Ph))(NCCH3)](BF4)2 (3) and [Fe(II)(N4Py(2Ph,amide))](BF4)2 (5). Controlled orientation of the Ph substituents in 3 leads to facile triplet spin reactivity for a putative Fe(IV)(O) intermediate, resulting in rapid arene hydroxylation. Addition of a peripheral amide substituent within hydrogen-bond distance of the iron first coordination sphere leads to stabilization of a high-spin Fe(III)OOR species which decays without arene hydroxylation. These results provide new insights regarding the impact of secondary coordination sphere effects at nonheme iron centers.

SUBMITTER: Sahu S

PROVIDER: S-EPMC3746373 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Secondary coordination sphere influence on the reactivity of nonheme iron(II) complexes: an experimental and DFT approach.

Sahu Sumit S Widger Leland R LR Quesne Matthew G MG de Visser Sam P SP Matsumura Hirotoshi H Moënne-Loccoz Pierre P Siegler Maxime A MA Goldberg David P DP

Journal of the American Chemical Society 20130715 29

The new biomimetic ligands N4Py(2Ph) (1) and N4Py(2Ph,amide) (2) were synthesized and yield the iron(II) complexes [Fe(II)(N4Py(2Ph))(NCCH3)](BF4)2 (3) and [Fe(II)(N4Py(2Ph,amide))](BF4)2 (5). Controlled orientation of the Ph substituents in 3 leads to facile triplet spin reactivity for a putative Fe(IV)(O) intermediate, resulting in rapid arene hydroxylation. Addition of a peripheral amide substituent within hydrogen-bond distance of the iron first coordination sphere leads to stabilization of ...[more]

PMID: 23834409

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