Der Pharma Chemica
Journal for Medicinal Chemistry, Pharmaceutical Chemistry, Pharmaceutical Sciences and Computational Chemistry


Study of Azo Ester Mesogens: 4-(4’-n-Alkoxy benzoyloxy)-3- Methoxy- phenyl azo-4”-Nitrobenzenes

Author(s): V.R. Patel and A.V.Doshi

New mesogenic homologous series having azo-ester central linkages was synthesized. All the homologues of the homologous series exhibit mesomorphism. Mesomorphism commences from the very first members of the series. Smectic mesophase commences from tenth homologue in addition to nematic mesophase. Sixteenth homologue is only smectogenic. The usual odd-even effect is observed in nematic-isotropic transition curve with alternation of transition temperature. Nematic-isotropic and smectic-isotropic (or Sm-N) transition curve behaves in a normal manner. Smectic-isotropic or smectic-nematic transition curve is extrapolated and merged to eighth homologue suggesting absence of smectic mesophase or showing up of only nematic mesophase. Thermal stability and mesomorphic characteristics are compared with other structurally similar known homologous series. Transition temperatures are observed through hot stage polarizing microscope. Analytical data support the structure of molecules.