Nonacyclic Ladder Silsesquioxanes and Spectral Features of Ladder Polysilsesquioxanes

Laddersiloxanes, that is, ladder silsesquioxanes with defined structures, could be obtained by stepwise synthesis starting from cyclic silanols. These compounds were shown to have high thermal stability. As an extension of the previous work, the first nonacyclic ladder silsesquioxanes were synthesized by the reaction of bicyclic silanol with tricyclic tetrachloride, which were obtained from cyclic silanols. The structure was confirmed by spectral measurements, and the spectral features of a series of ladder polysilsesquioxanes with determined structures were analyzed