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Abstract A new nonheme iron(II) complex, FeII(Me3TACN)((OSiPh2)2O) (1), is reported. Reaction of1with NO(g)gives a stable mononitrosyl complex Fe(NO)(Me3TACN)((OSiPh2)2O) (2), which was characterized by Mössbauer (δ=0.52 mm s−1, |ΔEQ|=0.80 mm s−1), EPR (S=3/2), resonance Raman (RR) and Fe K‐edge X‐ray absorption spectroscopies. The data show that2is an {FeNO}7complex with anS=3/2 spin ground state. The RR spectrum (λexc=458 nm) of2combined with isotopic labeling (15N,18O) reveals ν(N‐O)=1680 cm−1, which is highly activated, and is a nearly identical match to that seen for the reactive mononitrosyl intermediate in the nonheme iron enzyme FDPnor (ν(NO)=1681 cm−1). Complex2reacts rapidly with H2O in THF to produce the N‐N coupled product N2O, providing the first example of a mononuclear nonheme iron complex that is capable of converting NO to N2O in the absence of an exogenous reductant.
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Iron in a Cage: Fixation of a Fe(II)tpy 2 Complex by Fourfold Interlinking
Abstract The coordination sphere of the Fe(II) terpyridine complex1is rigidified by fourfold interlinking of both terpyridine ligands. Profiting from an octa‐aldehyde precursor complex, the ideal dimensions of the interlinking structures are determined by reversible Schiff‐base formation, before irreversible Wittig olefination provided the rigidified complex. Reversed‐phase HPLC enables the isolation of the all‐transisomer of the Fe(II) terpyridine complex1, which is fully characterized. While temperature independent low‐spin states were recorded with superconducting quantum interference device (SQUID) measurements for both, the open precursor8and the interlinked complex1, evidence of the increased rigidity of the ligand sphere in1was provided by proton T2relaxation NMR experiments. The ligand sphere fixation in the macrocyclized complex1even reaches a level resisting substantial deformation upon deposition on an Au(111) surface, as demonstrated by its pristine form in a low temperature ultra‐high vacuum scanning tunneling microscope experiment.
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- Award ID(s):
- 1764353
- PAR ID:
- 10165995
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 37
- ISSN:
- 1433-7851
- Format(s):
- Medium: X Size: p. 15947-15952
- Size(s):
- p. 15947-15952
- Sponsoring Org:
- National Science Foundation
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