Cobalt Superoxo and Alkylperoxo Complexes Derived from Reaction of Ring-Cleaving Dioxygenase Models with O₂

Authors

Praveen Kumar, Marquette University
Sergey V. Lindeman, Marquette UniversityFollow
Adam T. Fiedler, Marquette UniversityFollow

Document Type

Article

Language

eng

Publication Date

6-28-2019

Publisher

American Chemical Society

Source Publication

Journal of the American Chemical Society

Source ISSN

0002-7863

Original Item ID

doi:10.1021/jacs.9b05320

Abstract

The syntheses and O₂ reactivities of active-site models of cobalt-substituted ring-cleaving dioxygenases are presented. The pentacoordinate cobalt(II)-aminophenolate complex, [Co(Tp^Me2)(^tBu2APH)], gives rise to two distinct dioxygen adducts at reduced temperatures. The first is a paramagnetic (S = 1/2) cobalt(III)-superoxo species that was characterized with spectroscopic and computational techniques. The identity of the second Co/O₂ adduct was elucidated by X-ray crystallography, which revealed an unprecedented cobalt(III)-alkylperoxo structure generated by O₂ addition to the metal ion and ligand. These results provide synthetic precedents for proposed intermediates in the catalytic cycles of O₂-activating cobalt enzymes.

Comments

Accepted version. Journal of the American Chemical Society, Vol. 114, No. 28 (June 28, 2019): 10984-10987. DOI. © 2019 American Chemical Society. Used with permission.

Recommended Citation

Kumar, Praveen; Lindeman, Sergey V.; and Fiedler, Adam T., "Cobalt Superoxo and Alkylperoxo Complexes Derived from Reaction of Ring-Cleaving Dioxygenase Models with O₂" (2019). Chemistry Faculty Research and Publications. 1000.
https://epublications.marquette.edu/chem_fac/1000