Alternating polystannanes: synthesis, preparation, characterization and a computational study

Polystannanes have been synthesized by a number of useful routes. Generally, these polymers have been limited to homopolymers containing a single type of substituent. We now demonstrated a novel condensation polymerization utilizing dialkyl or diaryl tin dihydrides and dialkyl tin diamides to prepare alternating polymers with neighbouring tin centers possessing different group functionalities. Three new alternating polystannanes containing both organically solubilizing (n-Bu, Me) and less solubilizing (Ph) side groups as well as the homopolymer dibutylpolystannane have been prepared. A variety of closely related model tristannanes using the same synthetic methodology was also completed. We have also carried out a computational study of a number of model stannanes in order to optimize structures of the oligo- and polystannanes synthetically prepared and predict their spectral properties by using time dependent density functional theory (TD-DFT). This study has yielded results that can be influential in predicting chemical orientation, bonding properties and electronics.