Synthesis and transition temperatures of novel fluorinated chiral liquid crystals containing 1,4-tetrafluorophenylene units

To continue the search for novel series of fluorinated ferroelectric liquid crystals, an additional two series of 4-(S)-2-methylbutoxy]phenyl 4-(4-n-alkoxy-2,3,5,6-tetrafluorophenyl)ethynyl] benzoates (C) and 4-(n-alkoxy)phenyl 4-(4-(S)-2'-methylbutoxy-2,3,5,6-tetrafluorophenyl)] benzoates (D) have been synthesized. Polarizing microscopic textural observations and DSC measurements of the phase transitions of these novel compounds showed that compounds C were liquid crystals with a chiral nematic (N) phase and a monotropic chiral smectic C phase (S_c), and compounds D exhibited a chiral nematic (N) phase.