Synthesis and Mesomorphic Behavior of Novel Liquid-Crystalline Thiophene Derivatives

A new class of thiophene-based cholesteryl and ferrocenyl derivatives was synthesized and characterized by common analytical techniques. Liquid-crystalline properties were investigated by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). Thiophene-based cholesteryl derivatives show homeotropic liquid-crystalline phase sequence crystalsmectic Acholestericisotropic, whereas the ferrocenyl derivative is nonmesomorphic. The effects of thiophene ring, terminal group, and length of the polymethylene spacers on the mesomorphic behavior are discussed.