Synthesis of 'butterfly cage' based on double-decker silsesquioxane.

Novel polyhedral structures were prepared with a butterfly-shape comprised of oligosiloxane wings and a double- decker silsesquioxane (DDSQ) body. The compounds were synthesized in two steps from commercially available alkoxysilanes, and their structures were confirmed using spectroscopic methods and X-ray crystallography. Not like other phenyl-substituted cage silsesquioxanes, these butterfly cages show very good solubility in common organic solvents. The crystal structures clearly showed their unique features: a larger space with longer siloxane chains, and very flexible framework. Moreover, these compounds are thermally stable with a Td 5 (5% weight loss temperature) over 320 °C.