| Abstract: | Coordinatively Unsaturated Iron Chalcogenolate Complexes with Trigonal Planar Ligand Spheres – Synthesis, Properties, and Reactions with Nitrogen and Oxygen Donor Molecules The new bulky organo-selenium compound 2,4,6-triphenylbenzeneselenole ( 1 A ) was synthesized by a multistep-reaction from 1,3,5-triphenylbenzene. 1 A was converted by oxidation into the air-stable bis(2,4,6-triphenylphenyl)diselenide ( 1 B ), which was characterized by X-ray diffraction. The stepwise reaction of Fe2{N(SiMe3)2}4] with 1 A leads to the complexes Fe2(SeC6H2-2,4,6-Ph3)2{N(SiMe3)2}2] ( 2 ) and Fe2(SeC6H2-2,4,6-Ph3)4] ( 3 ), controlled by their molar ratios. The conversion of 2 to 3 is also described. In addition, the coordinatively unsaturated thiolate complexes Fe2{SC6H3-2,6-(SiMe3)2}2{N(SiMe3)2}2] ( 4 ) and Fe2{SC6H3-2,6-(SiMe3)2}4] ( 5 ) were synthesized by stepwise reaction of Fe2{N(SiMe3)2}4] with 2,6-bis(trimethylsilyl)benzenethiole. It is also possible to convert the heteroleptic compound 4 into the homoleptic thiolate complex 5 . During our investigations of the reactivity of 5 towards small electroneutral molecules, the compounds Fe2{SC6H3-2,6-(SiMe3)2}4 · (MeCN)2] ( 6 ) and Fe{SC6H3-2,6-(SiMe3)2}2(OPEt3)] ( 7 ) were obtained. 6 is the product of the addition of two molecules of acetonitrile to 5 . The iron atoms of 6 are coordinated by three sulfur and one nitrogen atom in a distorted tetrahedral manner. When 5 is treated with triethylphosphine oxide instead of acetonitrile, the mononuclear complex 7 with the coordination number three is formed. The iron atom is surrounded by two sulfur and one oxygen donor functions. |
