Synthesis of Cyclotetragermanes of the Type of [R(Ph)Ge]<sub>4</sub>and Conversion to [R(Cl)Ge]<sub>4</sub>. The First Functionalized Cyclotetragermanes
Condensations of R(Ph)GeCl2 (R = t-Bu and R = CEt2Me) with Mg/MgBr2 in THF produced cyclotetragermanes [R(Ph)Ge]4, which were converted to [R(Cl)Ge]4 by treatment with HCl/AlCl3 or with CF3SO3H followed by CH3COCl. The crystal structure of [t-Bu(Cl)Ge]4 was established by X-ray diffraction. Unusual configurational behavior of cyclotetragermanes is also described.