Fluorine-containing pyrimidine derivatives

摘要

Liquid crystalline fluorine-containing pyrimidine compounds have the formula I <IMAGE> wherein R1 and R2 are H, R, OR or OCOR, and one of them can also be CN or F, or, if A is a covalent bond, also one or both of R1 and R2 can be 4-R4-phenyl or 4-R-cyclohexyl, wherein R4 is R, OR, cyano, f or OCOR; wherein R is an alkyl group of 1 to 12 C atoms; R3 is F or, if one of the radicals R1 or R2 is F or 4-fluorophenyl, also H; Z is 1,3-pyrimidin-2,5-diyl; and A is 1,4-phenylene, 1,4-cyclohexylene or a covalent bond. Fluorine-containing pyrimidine compounds are useful components of liquid crystal dielectrics for electro-optical display devices.