New antiferroelectric compounds containing partially fluorinated terminal chains. Synthesis and mesomorphic properties

Methods for preparing optically active hydroxyesters: 1-hydroxy-4-(1-methyl heptyloxycarbonyl)benzene and 4-hydroxy-4'-(1-methylheptyloxy-carbonyl)biph enyl, 4-(1-methylheptyloxycarbonyl)phenyl 4'-hydroxybiphenyl-4-carboxylate and 4'-(1-methylheptyloxy carbonyl)biphenyl-4-yl 4-hydroxybenzoate have bee n elaborated. These compounds were used as intermediates for preparing liqu id crystalline homologous series of di- and triesters exhibiting tilted sme ctic phases C-A* and C*. The phase transitions have been measured by DSC an d thermomicroscopic methods and the smectic phases have been identified by microscopic textures and miscibility studies.