Liquid Crystalline Cyclotriphosphazenes: Full Substitute Trimeric Derivative with 12-carbon-chain Mesogen Moiety

Full substituted p-(dodecyloxy)-phenol derivative of cyclotriphosphazene (trimer) was synthesized in order to investigate its mesogenic properties. Firstly, p-(dodecyloxy)-phenol (1) was synthesized from the reaction of hydroquinone and 1-bromododecane. Hexachlorocyclotriphosphazene (trimer) was reacted in a 1:8 molar ratio in tetrahydrofurane (THF) presence of sodium hyride (NaH) as base at room temperature for 24 hours and then under the reflux for a day. Full substituted derivative (2) was obtained and its structure was determined by mass analysis, and by FT-IR, 1H and 31P {1H} NMR spectroscopic techniques. Additionally thermal and mesomorphic behaviours were examined by differential scanning calorimetry (DSC), polarising optical microscopy (POM) and X-ray diffraction (XRD) techniques. By contrast with literature, results showed that compound 2 has liquid crystal behavior.

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