Synthesis and mesomorphic properties of novel [1,2,3]-triazole mesogenic based compounds

A series of five-membered heterocyclic 1,2,3-triazole derivatives with different substituents in N1 position was synthesized. The heterocyclic moiety was connected through an ester function to a p-decyloxyphenyl or p-decyloxybiphenyl tails Polarized microscopy studies, X-ray scattering and differential scanning calorimetry (DSC) analysis revealed that the target compounds exhibit enantiotropic liquid crystalline properties. Their mesomorphic behavior is closely related to the nature of the substituent X present in N1 position of the heterocycle.

► Novel [1,2,3]-triazole based mesogenic derivatives were synthesized and characterized.
► The smectic A phase appeared to be the dominant phase in these structures.
► The incorporation of an ester function within the triazole unit could generate enough dipole which promotes the arrangement of molecules in smectic layer structures.
► The mesomorphic behavior is closely related to the nature of the substituent X present in N1 position of the heterocycle.
► The increase of the mesogenic length causes a decrease in the existence range of the smectic A mesophase in favor of a new nematic mesophase.