Mononuclear, Dinuclear, and Trinuclear Iron Complexes Featuring a New Monoanionic SNS Thiolate Ligand Uttam K. Das Stephanie L. Daifuku Serge I. Gorelsky Ilia Korobkov Michael L. Neidig Jennifer J. Le Roy Muralee Murugesu R. Tom Baker 10.1021/acs.inorgchem.5b02833.s003 https://acs.figshare.com/articles/dataset/Mononuclear_Dinuclear_and_Trinuclear_Iron_Complexes_Featuring_a_New_Monoanionic_SNS_Thiolate_Ligand/2086738 The new tridentate ligand, S<sup><i>Me</i></sup>N<sup><i>H</i></sup>S = 2-(2-methylthiophenyl)­benzothiazolidine, prepared in a single step from commercial precursors in excellent yield, undergoes ring-opening on treatment with Fe­(OTf)<sub>2</sub> in the presence of base affording a trinuclear iron complex, [Fe<sub>3</sub>(μ<sub>2</sub>-S<sup><i>Me</i></sup>NS<sup>–</sup>)<sub>4</sub>]­(OTf)<sub>2</sub> (<b>1</b>) which is fully characterized by structural and spectroscopic methods. X-ray structural data reveal that <b>1</b> contains four S<sup><i>Me</i></sup>NS<sup>–</sup> ligands meridionally bound to two pseudooctahedral iron centers each bridged by two thiolates to a distorted tetrahedral central iron. The combined spectroscopic (UV–vis, Mössbauer, NMR), magnetic (solution and solid state), and computational (DFT) studies indicate that <b>1</b> includes a central, high-spin Fe­(II) (<i>S</i> = 2) with two low-spin (<i>S</i> = 0) peripheral Fe­(II) centers. Complex <b>1</b> reacts with excess PMePh<sub>2</sub>, CNxylyl (2,6-dimethylphenyl isocyanide), and P­(OMe)<sub>3</sub> in CH<sub>3</sub>CN to form diamagnetic, thiolate-bridged, dinuclear Fe­(II) complexes {[Fe­(μ-S<sup><i>Me</i></sup>NS<sup>–</sup>)­L<sub>2</sub>]<sub>2</sub>}­(OTf)<sub>2</sub> (<b>2</b>–<b>4</b>). These complexes are characterized by elemental analysis; <sup>1</sup>H NMR, IR, UV–vis, and Mössbauer spectroscopy; and single crystal X-ray diffraction. Interestingly, addition of excess P­(OMe)<sub>3</sub> to complex <b>1</b> in CH<sub>2</sub>Cl<sub>2</sub> produces primarily the diamagnetic, mononuclear Fe­(II) complex, {Fe­(S<sup><i>Me</i></sup>NS<sup>–</sup>)­[P­(OMe)<sub>3</sub>]<sub>3</sub>}­(OTf) (<b>5</b>). 2016-01-19 00:00:00 Trinuclear Iron Complexes Featuring New Monoanionic SNS Thiolate LigandThe 1 H NMR IR UV Complex 1 CH 2Cl DFT spectroscopic methods tridentate ligand form diamagnetic CH 3CN trinuclear iron pseudooctahedral iron centers