Activation of Dichloromethane by an Iron(III) Methoxide Complex Binding with a Tris(thiolato)phosphine Ligand

Abstract

The iron centers ligated by S-donors are present in the actives sites of many metalloproteins In order to understand basic coordination chemistry of iron sulfur complexes we focus on the chemistry of iron species reacting with multidentate thiolato ligand PS3” (PS3” = [P(C6H3-3-Me3Si-2-S)3]3-) As a result an iron(III) methoxide complex [FeIII(PS3”)OCH3][PPh4] (1) was obtained by the reaction of iron(II) species with dioxygen in methanol Furthermore complex 1 was found to react with dichloromethane giving [FeIII(PS3”)Cl][PPh4] (2) The reactivity was monitored by UV-vis-NIR spectrum ESI-MS spectrum and NMR spectrum The formation of complex 2 demonstrates that C-Cl bond in dichloromethane was activated by complex 1 Complexes 1 and 2 were all well characterized by X-ray crystallography as well as other physical methods such as UV-vis-NIR spectrum ESI-MS spectrum NMR spectrum and SQUID The structures of both complexes adopt a trigonal bipyramidal geometry by binding to a tetradentate PS3” ligand and an axial co-ligand trans to the phosphine donor The magnetic studies indicate that both complexes have S=3/2 spin states consistent with d5 intermediate spin in trigonal bipyramidal geometry

Date of Award	2014 Aug 5
Original language	English
Supervisor	Konopka Richard L. (Supervisor)