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Novel Thermotropic Liquid Crystals with Lateral Aryl Substituent

Author Affiliations

  • 1Department of Applied Chemistry; Faculty of Technology and Engineering, The M.S. University of Baroda, Vadodara -390 001, Gujarat, INDIA

Res.J.chem.sci., Volume 4, Issue (9), Pages 22-26, September,18 (2014)

Abstract

A novel mesogenic homologous series 4 - carbethoxy 2’, 4’–bis (4”-n-alkoxy benzoyloxy) azobenzenes has been synthesized by fixing a rigid 4- carbethoxy phenyl azo group to a resorcinol moiety and both the phenolic hydroxyl groups are esterified by 4-n alkoxy benzoyl groups. The lower homologues of the series exhibit monotropic smectic mesophases whereas the higher homologues exhibit enantiotropic smectic mesophases. The synthesized compounds were characterized by a combination of elemental analysis and IR and NMR spectroscopy. Their mesomorphic properties are discussed and compared with those of structurally related homologous series. The impact of the lateral aryl segment on mesomorphism is also discussed.

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