Synthesis, Structures, and Multinuclear NMR Spectra of Tin(II) and Lead(II) Complexes of Tellurium-Containing Imidodiphosphinate Ligands: Preparation of Two Morphologies of Phase-Pure PbTe from a Single-Source Precursor

Group 14 metal complexes of heavy chalcogen-centered anions, M[(TePiPr2)2N]2 (5, M = Sn; 6, M = Pb) and M(TePiPr2NPiPr2Se)2 (7, M = Sn; 8, M = Pb), were synthesized in 64−89% yields by metathesis of alkali-metal salts of the ligands with group 14 metal dihalides. Crystallographic characterization of the complexes revealed that 5, 6, and 8 engage in metal···chalcogen secondary bonds to generate dimers, whereas 7 is monomeric in the solid state. Multinuclear (1H, 31P, 77Se, and 125Te) solution NMR data for these homoleptic complexes evinced dynamic behavior leading to the equivalence of the two ligand environments. The PbII complex 6 was utilized as a single-source precursor to micrometer-scale lead telluride particles via two divergent techniques: aerosol-assisted chemical vapor deposition of the complex in THF/CH2Cl2 solution onto glass substrates yielded rectangular prisms, while solution injection of 6 in tri-n-octylphosphine onto Si/SiO2(100) substrates heated to 200−220 °C resulted in the formation of wires. PXRD and EDX analysis of the products confirmed the phase purity of the PbTe materials.

通过配体的碱金属盐与第14族金属二卤化物发生复分解反应，以64%~89%的产率合成了一系列以重硫族元素为中心阴离子的第14族金属配合物：M[(TePiPr₂)₂N]₂（5，M=Sn；6，M=Pb）以及M(TePiPr₂NPiPr₂Se)₂（7，M=Sn；8，M=Pb）。对上述配合物的晶体结构表征结果显示，5、6和8通过金属…硫族次级键形成二聚体，而7在固态下为单体结构。对这些同配体配合物的多核（¹H、³¹P、⁷⁷Se、¹²⁵Te）溶液核磁共振谱数据的分析表明，体系存在动态行为，使得两种配体环境等价。铅(II)配合物6被用作单源前驱体，通过两种不同途径制备微米级碲化铅颗粒：将配合物溶解于四氢呋喃/二氯甲烷（THF/CH₂Cl₂）溶液中，经气溶胶辅助化学气相沉积至玻璃基底上，得到矩形棱柱体形产物；而将6溶解于三正辛基膦中后注入加热至200~220℃的Si/SiO₂(100)基底，则得到线状产物。对所得产物的X射线粉末衍射（Powder X-ray Diffraction，PXRD）与能量色散X射线光谱（Energy Dispersive X-ray Spectroscopy，EDX）分析证实了该碲化铅材料的相纯度。