| 摘要 |
NEW MATERIAL:A 2,3-dicyano-4-alkoxyphenyl 4-halogenobenzoate of formula I (R is 1-10C alkyl; X is F or Cl). USE:A liquid crystal composition, having a negative dielectric anisotropy value (DELTAepsilon) as large as about -15 and not so high viscosity, and capable of accelerating the reaction rate of a color liquid crystal display device made from the liquid crystal composition utilizing the above-mentioned compound with good stability to moisture, heat, light, etc. PREPARATION:A 4-halogenobezoyl chloride of formula II is reacted with a 2,3- dicyano-4-alkoxyphenol of formula III in the presence of pyridine to afford the aimed compound of formula I .
|
