CYCLOHEXYL- AND CYCLOHEXENYL-SUBSTITUTED LIQUID CRYSTALS WITH LOW BIREFRINGENCE

摘要

This invention provides compounds of formula R1-Ar-R2 wherein R1 and R2, independently of one another, are selected from the group consisting of alkyl, cycloalkyl, alkenyl, cycloalkenyl, alkynyl, alkoxy, thioalkyl, thioether and ether groups having from 1 to about 20 carbon atoms, wherein one or more -CH2- groups in R1 and R2 may be independently replaced with a member of the group consisting of O, S, -CH2O-, -OCH2-, -COO-, -OOC-, -CH2S-, -SCH2-, -COS-, -SCO-, a double bond, a triple bond, and an alkyl silyl group, Si(Re)(Rf), in which Re and Rf, independently of one another, are small akyl or alkenyl groups having from about 1 to about 8 carbon atoms, said R1 or R2, independently of one another, can be partially or fully halogenated, and said R1 or R2, independently of one another , can be internally or terminally branched; Ar is a ring core moiety of general formula (I) wherein Cyc is a cyclohexyl ring or a cyclohexenyl ring, which may be optionally substituted with members selected from the group consisting of halogen atoms, methyl groups, trifluoromethyl groups, cyano groups, methoxy groups, and trifluoromethoxy groups; RX, RY and RZ, independently of one another, are aromatic or non-aromatic rings which are selected from the group consisting of 1,4-phenyl, 2,5-pyridinyl, 2,5-pyrimidinyl, 2,5-pyrazinyl, 3,6-pyridazinyl, 2,5-dithiazolyl, 1,4-cyclohexyl, 1-4-cyclohex-2-enyl, and 1,4-cyclohexenyl rings, wherein any hydrogen in RX, RY and RZ may optionally be substituted with a halogen atom; wherein x, y, z are, independently of one another, 0, 1, or 2 such that x+y+z=1, 2, or 3; wherein A, B and D, independently of one another, are linkers selected from the group -(CH2)w-, wherein w is 0 to about 8, and wherein one or more -CH2- groups in A, B or D may be independently replaced with a member selected from the group consisting of O, S, -CH2O-, -OCH2-, -COO-, -OOC-, -CH2S-, -SCH2-, -COS-, -SCO-, a double bond, a triple bond, and an alkyl silyl group, Si(Re)(Rf), in which Re and Rf, independently of one another, are small alkyl or alkenyl groups having from about 1 to about 8 carbon atoms; wherein a, b, d, independently of one another, are 0 or 1, such that a+b+d=1,2,or 3.