title: A Triad of Highly Reduced, Linear Iron Nitrosyl Complexes: {FeNO}(8-10).
abstract: Given the importance of Fe-NO complexes in both human biology and the global nitrogen cycle, there has been interest in understanding their diverse electronic structures. Herein a redox series of isolable iron nitrosyl complexes stabilized by a tris(phosphine)borane (TPB) ligand is described. These structurally characterized iron nitrosyl complexes reside in the following highly reduced Enemark-Feltham numbers: {FeNO}(8) , {FeNO}(9) , and {FeNO}(10) . These {FeNO}(8-10) compounds are each low-spin, and feature linear yet strongly activated nitric oxide ligands. Use of Mössbauer, EPR, NMR, UV/Vis, and IR spectroscopy, in conjunction with DFT calculations, provides insight into the electronic structures of this uncommon redox series of iron nitrosyl complexes. In particular, the data collectively suggest that {TPBFeNO}(8-10) are all remarkably covalent. This covalency is likely responsible for the stability of this system across three highly reduced redox states that correlate with unusually high Enemark-Feltham numbers.
authors: Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125, USA.
authors: Matthew J
authors: MJ
authors: Chalkley
authors: Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125, USA. jpeters@caltech.edu.
authors: Jonas C
authors: 0000-0002-6610-4414
authors: JC
authors: Peters
mesh_terms: D001880:Boranes / Q000737:chemistry; D004583:Electrons; D007501:Iron / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D009589:Nitrogen Oxides / Q000737:chemistry*; D010084:Oxidation-Reduction; D011789:Quantum Theory
chemical_list: D001880:Boranes; D008024:Ligands; D009589:Nitrogen Oxides; C073661:dinitrosyl iron complex; D007501:Iron
keywords: boratrane; coordination modes; iron; metal-ligand covalency; nitrogen oxides