English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Electron Paramagnetic Resonance Signature of Tetragonal Low Spin Iron(V)-Nitrido and -Oxo Complexes Derived from the Electronic Structure Analysis of Heme and Non-Heme Archetypes

Chang, H.-C., Mondal, B., Fang, H., Neese, F., Bill, E., & Ye, S. (2019). Electron Paramagnetic Resonance Signature of Tetragonal Low Spin Iron(V)-Nitrido and -Oxo Complexes Derived from the Electronic Structure Analysis of Heme and Non-Heme Archetypes. Journal of the American Chemical Society, 141(6), 2421-2434. doi:10.1021/jacs.8b11429.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0005-A9F2-B Version Permalink: http://hdl.handle.net/21.11116/0000-0005-A9F3-A
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Chang, Hao-Ching, Author
Mondal, Bhaskar1, Author              
Fang, Huayi1, Author              
Neese, Frank2, Author              
Bill, Eckhard3, Author              
Ye, Shengfa, Author
Affiliations:
1Research Department Neese, Max Planck Institute for Chemical Energy Conversion, Max Planck Society, ou_3023886              
2Research Department Neese, Max-Planck-Institut für Kohlenforschung, Max Planck Society, ou_2541710              
3Research Department DeBeer, Max Planck Institute for Chemical Energy Conversion, Max Planck Society, ou_3023871              

Content

show
hide
Free keywords: -
 Abstract: Iron(V)-nitrido and -oxo complexes have been proposed as key intermediates in a diverse array of chemical transformations. Herein we present a detailed electronic-structure analysis of [Fe-V(N)(TPP)] (1, TPP2- = tetraphenylporphyrinato), and [Fe-V(N)(cyclam-ac)](+) (2, cyclam-ac = 1,4,8,11-tetraazacyclotetradecane-1-acetato) using electron paramagnetic resonance (EPR) and Fe-57 Mossbauer spectroscopy coupled with wave function based complete active-space self-consistent field (CASSCF) calculations. The findings were compared with all other well-characterized genuine iron(V)-nitrido and -oxo complexes, [Fe-V(N)(MePy(2)tacn)](PF6)(2) (3, MePy(2)tacn = methyl-N',N ''-bis(2-picolyl)-1,4,7-triazacyclononane), [Fe-V(N){PhB(t-BuIm)(3)}](+) (4, PhB((t)BuIm)(3)(-) = phenyltris(3-tert-butylimidazol-2-ylidene)borate), and [Fe-V(O)(TAML)](-) (5, TAML(4-) = tetraamido macrocyclic ligand). Our results revealed that complex 1 is an authenticated iron(V)-nitrido species and contrasts with its oxo congener, compound I, which contains a ferry] unit interacting with a porphyrin radical. More importantly, tetragonal iron(V)-nitrido and-oxo complexes 1-3 and 5 all possess an orbitally nearly doubly degenerate S = 1/2 ground state. Consequently, analogous near-axial EPR spectra with g(parallel to) < g(perpendicular to) <= 2 were measured for them, and their g(parallel to) and g(perpendicular to) values were found to obey a simple relation of g(perpendicular to)(2) + (2 - g(parallel to))(2) = 4. However, the bonding situation for trigonal iron(V)-nitrido complex 4 is completely different as evidenced by its distinct EPR spectrum with g(parallel to) < 2 < g(perpendicular to). Further in-depth analyses suggested that tetragonal low spin iron(V)-nitrido and-oxo complexes feature electronic structures akin to those found for complexes 1-3 and 5. Therefore, the characteristic EPR signals determined for 1-3 and 5 can be used as a spectroscopic marker to identify such highly reactive intermediates in catalytic processes.

Details

show
hide
Language(s): eng - English
 Dates: 2019
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: ISI: 000459222100035
DOI: 10.1021/jacs.8b11429
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Journal of the American Chemical Society
  Other : J. Am. Chem. Soc.
  Abbreviation : JACS
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Washington, DC : American Chemical Society
Pages: - Volume / Issue: 141 (6) Sequence Number: - Start / End Page: 2421 - 2434 Identifier: ISSN: 0002-7863
CoNE: https://pure.mpg.de/cone/journals/resource/954925376870