Silsesquioxane chemistry, 6 : The first beryllium silsesquioxane: synthesis and structure of [Cy7Si7O12BeLi]2·2THF

The compound [Cy7Si7O12BeLi]2·2THF (3) was prepared in high yield by reacting in situ prepared Cy7Si7O9(OLi)3 (2) with anhydrous BeCl2 in THF at 20°C. The molecular structure of 3 has been determined by X-ray diffraction and is the first structurally characterized silsesquioxane derivative of beryllium. In the solid state, self-assembly leads to the formation of a dimeric molecule.