title: Oxidative group transfer to a triiron complex to form a nucleophilic μ(3)-nitride, [Fe3(μ(3)-N)]-.
abstract: Utilizing a hexadentate ligand platform, a high-spin trinuclear iron complex of the type ((tbs)L)Fe(3)(thf) was synthesized and characterized ([(tbs)L](6-) = [1,3,5-C(6)H(9)(NPh-o-NSi(t)BuMe(2))(3)](6-)). The silyl-amide groups only permit ligation of one solvent molecule to the tri-iron core, resulting in an asymmetric core wherein each iron ion exhibits a distinct local coordination environment. The triiron complex ((tbs)L)Fe(3)(thf) rapidly consumes inorganic azide ([N(3)]NBu(4)) to afford an anionic, trinuclear nitride complex [((tbs)L)Fe(3)(μ(3)-N)]NBu(4). The nearly C(3)-symmetric complex exhibits a highly pyramidalized nitride ligand that resides 1.205(3) Å above the mean triiron plane with short Fe-N (1.871(3) Å) distances and Fe-Fe separation (2.480(1) Å). The nucleophilic nitride can be readily alkylated via reaction with methyl iodide to afford the neutral, trinuclear methylimide complex ((tbs)L)Fe(3)(μ(3)-NCH(3)). Alkylation of the nitride maintains the approximate C(3)-symmetry in the imide complex, where the imide ligand resides 1.265(9) Å above the mean triiron plane featuring lengthened Fe-N(imide) bond distances (1.892(3) Å) with nearly equal Fe-Fe separation (2.483(1) Å).
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors.forename: Tamara M
authors.initials: TM
authors.lastname: Powers
authors.forename: Alison R
authors.initials: AR
authors.lastname: Fout
authors.forename: Shao-Liang
authors.initials: SL
authors.lastname: Zheng
authors.forename: Theodore A
authors.initials: TA
authors.lastname: Betley
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D005290:Ferric Compounds; D007501:Iron