Synthesis and Mesomorphic Behavior of Azo-Cinnamate Containing Highly Polar Pyridine Derivatives

A new azo-based liquid crystalline compound, 4-(4’-n-alkoxy-3’-methoxy cinnamyloxy) phenyl azo-5’’-(2’’-cyano-3’’-trifluoromethyl) pyridine, was synthesized and characterized. The structure was confirmed by elemental analysis, FT-IR, and NMR spectroscopy. The molecular design, incorporating azo and ester linkages along with polar –CN and –CF₃ substituents on the pyridine ring, enhances molecular anisotropy and intermolecular interactions. Mesomorphic properties studied by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) revealed the presence of stable nematic and smectic phases. The results indicate that these compounds exhibit good thermal stability and are promising for applications in liquid crystal and photonic devices.