Germanium Compounds Containing GeE Double Bonds (E = S, Se, Te) as Single-Source Precursors for Germanium Chalcogenide Materials

New germanium chalcogenide precursors, SGe­(dmamp)₂ (3), SGe­(dmampS)₂ (4), SeGe­(dmamp)₂ (5), SeGe­(dmampS)₂ (6), TeGe­(dmamp)₂ (7), and TeGe­(dmampS)₂ (8), were synthesized from Ge­(dmamp)₂ (1) and Ge­(dmampS)₂ (2) using sulfur, selenium, and tellurium powders (dmamp = 1-dimethylamino-2-methyl-2-propanolate, dmampS = 1-dimethylamino-2-methylpropane-2-thiolate). Complexes 1 and 2 were synthesized from metathesis reactions of GeCl₂·dioxane with 2 equiv of aminoalkoxide or aminothiolate ligands. Thermogravimetric analysis of complex 1 displayed good thermal stability and volatility. The molecular structures of complexes 2–8 from X-ray single crystallography showed distorted trigonal bipyramidal geometry at the germanium centers. Germanium chalcogenide materials (GeSe and GeTe) were obtained from the thermal decomposition of complexes 5, 6, and 8 in hexadecane. X-ray diffraction patterns exhibited that GeSe and GeTe had orthorhombic and rhombohedral phases, respectively. This study affords a facile method to easily prepare germanium chalcogenide materials using well-designed and stable complexes by thermal decomposition of single-source precursors in solution.