SYNTHESIS OF CYCLOTRIPHOSPHAZENES CONTAINING CYANOSTILBENES WITH DIFFERENT TERMINAL SUBSTITUENTS

The synthesis and mesomorphic properties of a class of cyclotriphosphazenes containing cyanostilbene groups with different terminal substituents (-H, -CH3, -OCH3, -CN) are described. All the resulting compounds are characterized by H-1, C-13, and P-31 NMR, matrix-assisted laser desorption/ionization time of flight, and elemental analysis. The thermal behaviors of cyclotriphosphazene derivatives are studied by the means of differential scanning calorimetry and polarizing optical microscopy. Nematic phases are observed in cyclotriphosphazenes with terminal substituents (-CH3, -OCH3, CN).