New Schiff's bases containing 1,3,4-thiadiazole and 1,3,4-oxadiazole units: a study of the effect of the heterocyclic ring and the position of the lateral alkoxy group on liquid crystalline properties

Abstract

The synthesis of novel SchiOE's bases incorporating the ve-membered 1,3,4-thiadiazole (series 7, 9) and 1,3,4-oxadiazole (series 8, 10) rings have been prepared and their liquid crystalline properties studied. All compounds of series 7 exhibit an enantiotropic smectic C phase. No liquid crystalline properties were observed for the compounds of series 8-10. A study of the structure/mesomorphic activity relationship is also described.

Determination of Phase Transitions of <i>p</i>,<i>n</i>-Alkyloxy Benzoic Acid Mesogens Using Legendre Moments and Image Analysis

“…The homologue with a larger alkyloxy chain (12 carbon atoms) is the unique derivative which displays Smectic C phase with an extra broad range mesomorphic behaviour of 20˚C relative to the same compound in planar alignment. Perhaps, the length of the terminal chain might increase of the complex flexibility which in turn influences the interactions are an influence on mesophase arrangement to favour the formation of smectic phase [22]. [21].…”

Synthesis, Characterization and Mesomorphic Properties of New Rod-like Thiophene Based Liquid Crystals

“…Their applications as ferroelectric materials as well as potential materials for molecular electronic devices, such as organic field effect transistors, are of special interest. Heterocyclic compounds such as five-membered thiadiazole or thiophene rings can be incorporated into the principal structure of calamitic mesogens [35][36][37][38][39]. Sulfur containing heterocycles are important synthetic intermediates and have found a variety of applications in medicinal, agricultural, and materials chemistry [40][41].…”

Mesogenic quinazolone derivatives: synthesis and characterisation

“…Many mesogenic compounds containing heterocyclic rings such as pyridine, pyrimidine, furyl, thiazole, thiadiazole and oxadiazole have been reported in the literature [1][2][3][4][5][6][7]. Significant interest in mesomorphic heterocyclic compounds [2] has dramatically increased due to their more diversified structural figures and distinct mesomorphic properties.…”