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Deciphering the mechanism of O₂ reduction with electronically tunable non-heme iron enzyme model complexes.

ABSTRACT: A homologous series of electronically tuned 2,2',2''-nitrilotris(N-arylacetamide) pre-ligands (H₃L^R ) were prepared (R = NO₂, CN, CF₃, F, Cl, Br, Et, Me, H, OMe, NMe₂) and some of their corresponding Fe and Zn species synthesized. The iron complexes react rapidly with O₂, the final products of which are diferric mu-oxo bridged species. The crystal structure of the oxidized product obtained from DMA solutions contain a structural motif found in some diiron proteins. The mechanism of iron mediated O₂ reduction was explored to the extent that allowed us to construct an empirically consistent rate law. A Hammett plot was constructed that enabled insightful information into the rate-determining step and hence allows for a differentiation between two kinetically equivalent O₂ reduction mechanisms.

SUBMITTER: Surendhran R

PROVIDER: S-EPMC6050603 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Deciphering the mechanism of O2 reduction with electronically tunable non-heme iron enzyme model complexes.

Surendhran Roshaan R D'Arpino Alexander A AA Sciscent Bao Y BY Cannella Anthony F AF Friedman Alan E AE MacMillan Samantha N SN Gupta Rupal R Lacy David C DC

Chemical science 20180605 26

A homologous series of electronically tuned 2,2',2''-nitrilotris(N-arylacetamide) pre-ligands (H3LR ) were prepared (R = NO2, CN, CF3, F, Cl, Br, Et, Me, H, OMe, NMe2) and some of their corresponding Fe and Zn species synthesized. The iron complexes react rapidly with O2, the final products of which are diferric mu-oxo bridged species. The crystal structure of the oxidized product obtained from DMA solu ...[more]

PMID: 30079187

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Deciphering the mechanism of O₂ reduction with electronically tunable non-heme iron enzyme model complexes.

Publications

Deciphering the mechanism of O<sub>2</sub> reduction with electronically tunable non-heme iron enzyme model complexes.

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