Abstract
In continuation with our work on liquid crystals with unconventional molecular structures, two homologous series that have 1,4-disubstitution and 1,3,4-trisubstitution in the central phenyl ring, such as 2[(4-n-alkoxy-benzyloxy) phenyl azomethine]-5-methyl thiazole and 2-[(4-n-alkoxy-benzyloxy)-2-hydroxy salicyladimine]-5-methyl thiazole, have been synthesized. They have been characterized by elemental analysis, FT-IR, 1HNMR, 13CNMR, and mass spectrometry. The liquid-crystalline behavior of these compounds was observed by differential scanning calorimetry (DSC) and polarizing microscopy. All the compounds of the 1,4-disubstituted series show an enantiotropic nematic phase only, whereas the compounds of the 1,3,4-trisubstituted series show smectic and nematic phases. Some mesogens with a lateral hydroxy group were also synthesized to evaluate the effect of this group on melting point, transition temperatures, and mesophase morphology.
ACKNOWLEDGMENT
We are thankful to I. I. T. Bombay, CDRI Lucknow, and Garda Chemicals Ltd., Ankleshwar, Gujarat, for providing elemental analysis, FT-IR, 1H NMR, mass, and thermal studies.
Notes
Note. Cr, crystal; SmC, smectic C; N, nematic; I, isotropic.
Note. SmC, smectic C; N, nematic; I, isotropic.
Note. Sm, smectic; N, nematic; I, isotropic.