Aminotroponiminatogermaacid Halides with a Ge(E)X Moiety (E = S, Se; X = F, Cl)

Fluorination of aminotroponiminate (ATI) ligand-stabilized germylene monochloride [(t-Bu)2ATI]­GeCl (1) with CsF gave the aminotroponiminatogermylene monofluoride [(t-Bu)2ATI]­GeF (2). Oxidative addition reaction of compound 2 with elemental sulfur and selenium led to isolation of the corresponding germathioacid fluoride [(t-Bu)2ATI]­Ge­(S)F (3) and germaselenoacid fluoride [(t-Bu)2ATI]­Ge­(Se)F (4), respectively. Similarly, reaction of aminotroponiminatogermylene monochloride [(i-Bu)2ATI]­GeCl (9) with elemental sulfur and selenium gave the aminotroponiminatogermathioacid chloride [(i-Bu)2ATI]­Ge­(S)Cl (11) and aminotroponiminatogermaselenoacid chloride [(i-Bu)2ATI]­Ge­(Se)Cl (12), respectively. Compound 9 has been prepared through a multistep synthetic route starting from 2-(tosyloxy)­tropone 5. All compounds (2–4 and 6–12) were characterized through the multinuclear NMR spectroscopy, and single-crystal X-ray diffraction studies were performed on compounds 2, 4, and 8–12. The germaselenoacid halide complexes 4 and 12 showed doublet (−142.37 ppm) and singlet (−213.13 ppm) resonances in their 77Se NMR spectra, respectively. Germylene monohalide complexes 2 and 9 have a germanium center in distorted trigonal pyramidal geometry, whereas a distorted tetrahedral geometry is seen around the germanium center in germaacid halide complexes 4, 11, and 12. The length of the GeE bond in germathioacid chloride (11) and germaselenoacid halide (4 and 12) complexes is 2.065(1) and 2.194av Å, respectively. Theoretical studies (based on the DFT methods) on complexes 4, 11, and 12 reveal the nature of the GeE multiple bond in these germaacid halide complexes with computed Wiberg bond indices (WBI) being 1.480, 1.508, and 1.541, respectively.以二(叔丁基)氨基卓亚胺基（aminotroponiminate, ATI）配体稳定的一氯化锗烯[(t-Bu)₂ATI]GeCl（1）与氟化铯（CsF）发生氟化反应，得到二(叔丁基)氨基卓亚胺基一氟锗烯[(t-Bu)₂ATI]GeF（2）。化合物2与单质硫、单质硒分别发生氧化加成反应，可分离得到相应的二(叔丁基)氨基卓亚胺基硫代锗酰氟[(t-Bu)₂ATI]Ge(S)F（3）与二(叔丁基)氨基卓亚胺基硒代锗酰氟[(t-Bu)₂ATI]Ge(Se)F（4）。类似地，二(异丁基)氨基卓亚胺基一氯化锗烯[(i-Bu)₂ATI]GeCl（9）与单质硫、单质硒反应，分别得到二(异丁基)氨基卓亚胺基氯化硫代锗酰[(i-Bu)₂ATI]Ge(S)Cl（11）与二(异丁基)氨基卓亚胺基氯化硒代锗酰[(i-Bu)₂ATI]Ge(Se)Cl（12）。化合物9是以2-(对甲苯磺酰氧基)卓酮（2-(tosyloxy)tropone）5为起始原料，通过多步合成路线制备得到。所有化合物（2~4及6~12）均通过多核核磁共振波谱法完成表征，且对化合物2、4以及8~12开展了单晶X射线衍射分析。硒代锗酰卤化物配合物4和12分别在其⁷⁷Se核磁共振谱中呈现出二重峰（δ -142.37 ppm）与单峰（δ -213.13 ppm）的共振信号。一卤化锗烯配合物2和9的锗中心处于畸变三角锥几何构型，而硫代/硒代锗酰卤化物配合物4、11和12的锗中心则呈现畸变四面体几何构型。氯化硫代锗酰配合物（11）以及硒代锗酰卤化物配合物（4和12）中的Ge=E键长分别为2.065(1) Å与2.194（平均）Å。针对配合物4、11和12开展的理论研究（基于密度泛函理论（DFT）方法）揭示了此类锗酰卤化物配合物中Ge=E多重键的本质，其计算得到的威伯格键级（Wiberg Bond Index, WBI）分别为1.480、1.508和1.541。