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Abstract S/N crosstalk species derived from the interconnected reactivity of H2S and NO facilitate the transport of reactive sulfur and nitrogen species in signaling, transport, and regulatory processes. We report here that simple Fe2+ions, such as those that are bioavailable in the labile iron pool (LIP), react with thionitrite (SNO−) and perthionitrite (SSNO−) to yield the dinitrosyl iron complex [Fe(NO)2(S5)]−. In the reaction of FeCl2with SNO−we were able to isolate the unstable intermediate hydrosulfido mononitrosyl iron complex [FeCl2(NO)(SH)]−, which was characterized by X‐ray crystallography. We also show that [Fe(NO)2(S5)]−is a simple synthon for nitrosylated Fe−S clusters via its reduction with PPh3to yield Roussin's Red Salt ([Fe2S2(NO)4]2−), which highlights the role of S/N crosstalk species in the assembly of fundamental Fe−S motifs.
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Single‐Step Sulfur Insertions into Iron Carbide Carbonyl Clusters: Unlocking the Synthetic Door to FeMoco Analogues
Abstract The one‐step syntheses, X‐ray structures, and spectroscopic characterization of synthetic iron clusters, bearing either inorganic sulfides or thiolate with interstitial carbide motifs, are reported. Treatment of iron carbide carbonyl clusters [Fen(μn‐C)(CO)m]x(n=5,6;m=15,16;x=0,−2) with electrophilic sulfur sources (S2Cl2, S8) results in the formation of several μ4‐S dimers of clusters, and moreover, iron‐sulfide‐(sulfocarbide) clusters. The core sulfocarbide unit {C−S}4−serves as a structural model for a proposed intermediate in the radicalS‐adenosyl‐L‐methionine biogenesis of the M‐cluster. Furthermore, the electrophilic sulfur strategy has been extended to provide the first ever thiolato‐iron‐carbide complex: an analogous reaction with toluylsulfenyl chloride affords the cluster [Fe5(μ5‐C)(SC7H7)(CO)13]−. The strategy described herein provides a breakthrough towards developing syntheses of biomimetic iron‐sulfur‐carbide clusters like FeMoco.
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- Award ID(s):
- 1808311
- PAR ID:
- 10204892
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 133
- Issue:
- 7
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 3475-3479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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