Mesomorphic behavior of new benzothiazole liquid crystals having Schiff base linker and terminal methyl group

A homologous series of heterocycles, 6-methyl-2-(4-alkoxybenzylidenamino)benzothiazoles, were synthesized and characterized using FT-IR, 1H and 13C NMR and mass spectrometric analysis. Enantiotropic nematic phase was observed for shorter members. Smectic A phase only emerged from octyloxy derivative onwards. The terminal methyl group at the benzothiazole fragment and the Schiff base linkage influenced the mesomorphic behavior of the present series.