New mono- and diethynylsiloxysilsesquioxanes--efficient procedures for their synthesis.

Ethynyl-substituted siloxysilsesquioxanes are promising building blocks for a wide range of substances based on a POSS/DDSQ core, especially for (oligo-)polymer syntheses and modifications (the formation of hybrid materials with interesting photophysical and mechanical properties). In this study, we report on a series of new mono- and diethynylsiloxysilsesquioxanes formed via an efficient and highly selective one-pot process from silsesquioxanes with reactive Si-OH groups based on sequential condensation, hydrolysis, chlorination and substitution reactions. All newly synthesized compounds were isolated and characterized by spectroscopic methods.