Synthesis and characterization of cyclopentadienyl thiolato complexes of magnesium

Abstract

Treatment of Cp 2Mg with 2-methyl-2-propanethiol, cyclohexanethiol, and 2-propanethiol in toluene at ambient temperature afforded the tetrameric cyclopentadienyl thiolato complexes [(η 5-Cp)Mg(μ 3-S t Bu)] 4 (97%), [(η 5-Cp)Mg(μ 3-S(C 6H 11))] 4 (92%), and [(η 5-Cp)Mg(μ 3-S i Pr)] 4 (83%) as colorless crystalline solids. Treatment of [(η 5-Cp)Mg(μ 3-S t Bu)] 4 with tetrahydrofuran or tert-butylpyridine in dichloromethane/hexane afforded the dimeric solvated complexes [(η 5-Cp)Mg(μ 2-S t Bu)(THF)] 2 (78%) or [(η 5-Cp)Mg(μ 2-S t Bu)( t Bupy)] 2 (60%) as colorless crystals. The crystal structures of [(η 5-Cp)Mg(μ 3-S t Bu)] 4, [(η 5-Cp)Mg(μ 2-S t Bu)(THF)] 2, and [(η 5-Cp)Mg(μ 2-S t Bu)( t Bupy)] 2 were determined by X-ray diffraction methods. In the solid-state structure, [(η 5-Cp)Mg(μ 3-S t Bu)] 4 contains one η 5-cyclopentadienyl ligand per magnesium and one cubic core of Mg 4S 4 that features a mirror plane of symmetry along one diagonal Mg 2S 2 plane. [(η 5-Cp)Mg(μ 2-S t Bu)(THF)] 2 contains one η 5-cyclopentadienyl ligand per magnesium and one bent Mg 2S 2 core with a mirror plane along thiolato bridges. [(η 5-Cp)Mg(μ 2-S t Bu)( t Bupy)] 2 contains one η 5-cyclopentadienyl ligand per magnesium and a planar Mg 2S 2 core with a center of symmetry.