A New Route to Heterosilsesquioxane Frameworks.

The substitution of an O atom in the Cy Si O framework by a heteroatom or a heteroatom-containing group (Z) provides a simple route to discrete heterosilsesquioxane frameworks 1. In this reaction the Cy Si O framework is initially opened with triflic acid and then treated with different nucleophiles (Cy=cyclohexyl; Z=NPh, SO , nBuBO , CrO ).