A Mononuclear Iron(II) Bis(guanidinate) Complex: Synthesis, Structure, and Reactivity

Abstract

A mononuclear, 14-electron iron(II) bis(guanidinate) complex, [Fe(HGua)2] [HGua– = (2,6-Me2C6H3N)C(NHiPr)(NiPr)–] (3), was easily prepared by treatment of anhydrous FeCl2 with 2 equiv. of [Li(HGua)(tmeda)] (2, tmeda = Me2NCH2CH2NMe2). Complex 3 reacts readily with AgCl, Br2, and I2, respectively, leading to the formation of the corresponding iron(III) bis(guanidinate) halide complexes [Fe(HGua)2X] {X = Cl (4), Br (5), I (6)}. Addition of 3 to elemental selenium gives a di-iron(III) µ-selenido complex [{Fe(HGua)2}2(µ-Se)] (9). Complex 3 also reacts readily with PhEEPh (E = S, Se), affording the respective iron(III) bis(guanidinate) chalcogenolate complexes [Fe(HGua)2(EPh)] {E = S (7), Se (8)}. A subsequent reaction of the iron(III) phenylselenolate complex [Fe(HGua)2(SePh)] (8) with I2 yields a mixture of [Fe(HGua)2I] (6) and an interesting selenium compound [(HGua)2SeI2] (10).