Tolane liquid crystals with piperidine, 3,3,4,4,5,5-hexafluoropiperidine as end group: Synthesis and properties

A series of new tolane liquid crystals with piperidine and 3,3,4,4,5,5-hexafluoropiperidine as their terminal groups were synthesized. Most of these new compounds exhibit SmB or SmG mesophase, good thermal stabilities and high clearing points. Fluorinated liquid crystals have a higher oxidation potential, dipole moment and broader HOMO-LUMO energy gap than the corresponding piperidine compounds.