Synthesis and mesomorphic properties of azoester mesogens 4-( 4' -n-alkoxy benzoyloxy)-2-methyl phenylazo-4"-methoxy benzenes

Chemistry Department, Smt. D. J. Shah Parivar Science College, Dholka-387 810, Gujarar, India E-mail : ngmakwana@yahoo.com Chemistry Depmtment, Matushri Virbaima Mahila Science and Home Science College, Rajkot-360 007, Gujarat, India Manuscript received 26 September 2006, revised 23 November 2007, accepted 26 November 2007 A new homologous series of azomesogens, 4-(4'-n-alkoxy benzoyloxy)-2-methyl phenylazo-4"-methoxy benzenes is synthesized. Mesomorphism commences from the very first homologue of the series and continues upto tetradecyl derivative. Last hexadecyl derivative is nonmesomorpbic. All mesomorphic homologues are enantiotropic nematic. Thus, present homologous series is purely nematogenic. The usual odd-even effect is observed in nematic-isotropic transition curve. Transition curve behaves in a normal manner. The average thermal stability and mesomorphic characteristics arc compared with structurally similar homologous series. Series is of middle ordered melting type without display of smectic character even in the last member of the series