Synthesis and liquid crystalline properties of a series of cholesterol-based dimesogenic compounds

The synthesis and mesomorphic properties of a series of novel dimesogenic compounds containing the cholesteryl ester unit and a phenyl benzoate group are reported. The two mesogenic units of these compounds are linked through dicarboxylic ester bonds, with alkylene spacer lengths of 2, 4, 6 and 8 methylene units. The chemical structures and liquid crystalline properties of this series of compounds were characterized by FTIR, ¹H NMR, hot stage-coupled polarizing microscopy and DSC. The results show that this series of compounds are cholesteric liquid crystals over a wide range, both during heating and cooling, and they exhibit iridescent colours in the liquid crystalline state.