Synthesis and study of new ester homologous series of Mesomorphs:4-Ethoxy phenyl-4â-n-alkoxy benzoates

The titled homologous series was synthesized by condensing n-alkoxy benzoyl chloride with 4- Hydroxy phenol in pyridine and studied with a view to understand effect of molecular structure on mesomorphic properties. All the nine members of the series except ethoxy derivative, are mesomorphic monotropically or enatiotropically with or without smectogenic property, in addition to nematic property. Odd-even effect is missing in a phase diagram plotted for number of carbon atoms in left n-alkyl chain of alkoxy terminal versus transition temperatures as observed from hot stage polarizing microscope. Series is predominantly nematogenic and partly smectogenic with mesophase length 100C to 380C. Mesomorphic properties are compared with structurally similar homologous series.