PROPIONIC ACID DERIVATIVE AND LIQUID CRYSTAL COMPOSITION THEREOF

摘要

NEW MATERIAL:The compound of formula I (R is <=20C alkyl; X is H, F or Cl bonded to o- or m-position based on RO-; n is 0 or 1; Z is 1-12C alkyl; *represents asymmetric carbon). EXAMPLE:Optically active [4-dodecyloxyphenylcarbonyloxy]-phenyl 2- ethoxypropionate. USE:Useful as a component of a liquid crystal composition or a photo-switching element for liquid crystal display cell. It enantiotropically exhibits chiral smectic C phase (SC* phase) over a wide range and largely varies the temperature range of SC* phase. PREPARATION:The compound of formula I can be produced either by the ester-condensation reaction of a compound of formula II with a compound of formula III using N,N-dicyclohexylcarbodiimide or by the condensation reaction of the compound of formula III with a corresponding acid halide of the compound of formula II.