Thiophene derived rod-shaped organic molecules: Synthesis and characterization of liquid crystal properties

Abstract

A new set of thiophene-derived organic rod-shaped molecules was synthesized, characterized, studied for their mesomorphic and optical behavior, as well as their thermal behaviors. In all the molecules, 5-bromothiophene-2-carboxylic acid is connected to the other part of the molecule via an ester bond. Chemical structures were confirmed by various analytical instrumentation methods. The mesomorphic properties were evaluated using differential scanning calorimetry (DSC) and polarized optical microscope (POM). Thermal stability was studied using thermogravimetric analysis (TGA). Five molecules were favored to exhibit liquid crystalline nematic mesophase; the remaining four molecules did not show liquid crystal properties. Two molecules are favored to grow as a single crystal, and the same property has been used to evaluate single-crystal X-ray studies.