A higher yielding route for T8 silsesquioxane cages and X-ray crystal structures of some novel spherosilicates

The synthesis of T8 silsesquioxane cages from trialkoxysilanes using tetra n-butylammonium fluoride is described. The yields are in the range 20-95%, which is a great improvement on other literature routes. This methodology enables a wide range of functionalised T8 cages to be prepared. The X-ray crystal structures of three new T8 cages, octacyclopentylsilsesquioxane, octaisobutylsilsesquioxane and octa(4-carboxymethyl-3,3-dimethylbutyl)silsesquioxane are also reported.