Cyclic and high molecular weight chiral binaphthoxy-phosphazene polymers carrying Br or trimethylsilyl-acetylene groups

The new chiral and functionalized cyclic binaphthoxyphosphazenes R,R,R-[N3P3(O2C20H10Br2)3] (R-1), R,R,R-[N3P3(O2C20H10(Ctriple bond; length of mdashCSiMe3)2)3] (R-2), and the high molecular weight linear polymers R/S-[NP(O2C20H10Br2)]n (R/S-3), R-[NP(O2C20H10Br2)]n (R-3), and R-{NP[O2C20H10(Ctriple bond; length of mdashCSiMe3)2]}n, (R-4), with Mw on the order of 106 and very high Tg, have been synthesized and characterized by IR and NMR spectroscopy. The optically active polymer (R-3) was configurationally stable below 300 °C, but at higher temperatures an atropisomerization process took place that became faster near the glass transition temperature (ca. 350 °C).