Cholesteryl benzoate derivatives: synthesis, transition property and cholesteric liquid crystal glass

Two series of cholesteryl p-(-bromoalkyloxy)benzoates and dimeric compounds of cholesteryl benzoate were synthesised, and their transition properties were studied. These compounds exhibited cholesteric phase during wide temperature range. The dimeric compounds showed the odd-even effect of the transition temperature, depending on the number of atoms in the flexible spacer. A reaction of adenine, thymine and cytosine with cholesteryl p-(-bromoalkyloxy)benzoates gave the corresponding liquid crystalline nucleic acid bases substituted with cholesteryl benzoate group. When these cholesteryl benzoate derivatives at cholesteric phase were rapidly cooled, cholesteric liquid crystal glasses were obtained. The reflection colour was affected by a combination of the cholesteryl benzoate derivatives.