(Lithioaryloxy)phosphazenes have been used as reaction intermediates for the synthesis of phosphazenes that bear organosilicon side groups. The synthetic pathways were developed at two levels, first with the use of small-molecule cyclic phosphazenes as reaction models and second with high polymeric phosphazenes. The cyclic small molecule N3P3(OPh)5OC6H4Br-p was first lithiated to N3P3(OPh)5OC6H4Li-p, and this compound was allowed to react with a range of organochlorosilanes or with hexamethylcyclotrisiloxane to yield the species N3P3(OPh)5OC6H4R-p, where R is SiMe3, SiMe2Ph, SiMePh2, SiMe2CH=CH2, SiMe2-(OSiMe2)2OSiMe2Bu, and SiMe2(OSiMe2)2OSiMe3. At the high polymer level, the macromolecule [NP-(OC6H4Br)2]nwas subjected to partial lithiation followed by coupling to chlorosilanes or to ring-opening addition of (OSiMe2)3to generate polymers with OC6H5and OC6H4Br-p side groups as well as OC6H4R-p units, where R’ is SiMe3, SiMe2Ph, SiMePh2, or SiMe2(OSiMe2)2OSiMe3. Molecular structural characterization was obtained by NMR, IR, microanalytical, and mass spectrometric methods. Glass transition temperatures for the high polymers were in the range +45 to -68 °C.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Inorganic Chemistry
- Materials Chemistry