TY - JOUR
T1 - The Fe2(NO)2 Diamond Core
T2 - A Unique Structural Motif In Non-Heme Iron–NO Chemistry
AU - Dong, Hai T.
AU - Speelman, Amy L.
AU - Kozemchak, Claire E.
AU - Sil, Debangsu
AU - Krebs, Carsten
AU - Lehnert, Nicolai
N1 - Publisher Copyright:
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2019/12/2
Y1 - 2019/12/2
N2 - Non-heme high-spin (hs) {FeNO}8 complexes have been proposed as important intermediates towards N2O formation in flavodiiron NO reductases (FNORs). Many hs-{FeNO}8 complexes 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}7 complex, [Fe(TPA)(NO)(OTf)](OTf) (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 that 2 is formed from dimerization of the hs-{FeNO}8 intermediate, followed by a spin state change of the iron centers to low-spin (ls), and speculate that 2 models intermediates in hs-{FeNO}8 complexes that precede the disproportionation reaction.
AB - Non-heme high-spin (hs) {FeNO}8 complexes have been proposed as important intermediates towards N2O formation in flavodiiron NO reductases (FNORs). Many hs-{FeNO}8 complexes 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}7 complex, [Fe(TPA)(NO)(OTf)](OTf) (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 that 2 is formed from dimerization of the hs-{FeNO}8 intermediate, followed by a spin state change of the iron centers to low-spin (ls), and speculate that 2 models intermediates in hs-{FeNO}8 complexes that precede the disproportionation reaction.
UR - https://www.scopus.com/pages/publications/85073073431
UR - https://www.scopus.com/inward/citedby.url?scp=85073073431&partnerID=8YFLogxK
U2 - 10.1002/anie.201911968
DO - 10.1002/anie.201911968
M3 - Article
C2 - 31550416
AN - SCOPUS:85073073431
SN - 1433-7851
VL - 58
SP - 17695
EP - 17699
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
IS - 49
ER -