Non‐heme high‐spin (hs) {FeNO}8complexes have been proposed as important intermediates towards N2O formation in flavodiiron NO reductases (FNORs). Many hs‐{FeNO}8complexes disproportionate by forming dinitrosyl iron complexes (DNICs), but the mechanism of this reaction is not understood. While investigating this process, we isolated a new type of non‐heme iron nitrosyl complex that is stabilized by an unexpected spin‐state change. Upon reduction of the hs‐{FeNO}7complex, [Fe(TPA)(NO)(OTf)](OTf) (
Non‐heme high‐spin (hs) {FeNO}8complexes have been proposed as important intermediates towards N2O formation in flavodiiron NO reductases (FNORs). Many hs‐{FeNO}8complexes disproportionate by forming dinitrosyl iron complexes (DNICs), but the mechanism of this reaction is not understood. While investigating this process, we isolated a new type of non‐heme iron nitrosyl complex that is stabilized by an unexpected spin‐state change. Upon reduction of the hs‐{FeNO}7complex, [Fe(TPA)(NO)(OTf)](OTf) (
- PAR ID:
- 10121962
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 58
- Issue:
- 49
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 17695-17699
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract 1 ), the N‐O stretching band vanishes, but no sign of DNIC or N2O formation is observed. Instead, the dimer, [Fe2(TPA)2(NO)2](OTf)2(2 ) could be isolated and structurally characterized. We propose that2 is formed from dimerization of the hs‐{FeNO}8intermediate, followed by a spin state change of the iron centers to low‐spin (ls), and speculate that2 models intermediates in hs‐{FeNO}8complexes that precede the disproportionation reaction. -
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