Abstract
Precision design of structure and function of silicon-containing oligomers and polymers is described based on the precise control of the reactivity and stereochemistry of silicon compounds. Firstly, conversion of oxy anion to carbanion was achieved by the aid of the ring-opening of silacy-clobutane derivatives by oxy anion, which was used to synthesize multi-block copolymers from epoxide and vinyl monomers. Secondly, synthesis of polycarbosiloxane was described based on newly found dehydrogenation reactions to give siloxane bonds from silane and silanol in the presence of various catalysts. Thirdly, stereo-chemical aspect of reactions of silicon compounds, and control of stereoregularity and optical activity of silicon-containing polymeric systems were described. Syndiotactic polysiloxanes was synthesized for the first time. Finally, structural control of polyhedral oligomeric silsesquioxanes was described. Cis sym cyclic tetrasiloxane was proved to be an important intermediate to form polyhedral oligomeric silsesquioxanes with various structures. A possible reaction mechanism was proposed for the formation of oligosilsesquioxane with controlled structure. Some applications of these compounds were also described.
