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.