申请人:Hoffmann-La Roche Inc.
公开号:US04925278A1
公开(公告)日:1990-05-15
Compounds of the formula ##STR1## wherein m represents is the number 0 or 1; A is a single covalent bond, --CH.sub.2 --CH.sub.2 --, --OCH.sub.2 --, --COO-- or --OOC--; rings B, C and D are 1,4-phenylene optionally substituted with cyano, halogen or lower alkyl; Y.sup.1 and Y.sup.2 are hydrogen or one of them also is cyano; and R.sup.1 and R.sup.2 each represents C.sub.1 -C.sub.18 -alkyl or C.sub.2 -C.sub.18 alkenyl, either of which is optionally halogen-substituted, in which one CH.sub.2 group or two non-adjacent CH.sub.2 groups is/are optionally replaced by oxygen; with the provisos that at least one of R.sup.1 and R.sup.2 has a chiral carbon atom or a C-C double bond or both when A is --COO-- and at least one of R.sup.1 and R.sup.2 has a C-C double bond when A is a single covalent bond, their preparation, liquid crystalline mixtures containing these compounds and their use for electro-optical purposes are described.
化合物的公式为## STR1 ##,其中m表示数字0或1; A是单个共价键,-CH.sub.2 -CH.sub.2 -,-OCH.sub.2 -,-COO-或-OOC-;环B,C和D是1,4-苯撑基,可选择用氰基,卤素或低碳基取代; Y.sup.1和Y.sup.2是氢或其中之一也是氰基; R.sup.1和R.sup.2分别表示C.sub.1-C.sub.18-烷基或C.sub.2-C.sub.18烯基,其中任意一个可以选择用卤素取代,其中一个CH.sub.2基团或两个非相邻的CH.sub.2基团可以被氧取代; 前提是当A是-COO-时,R.sup.1和R.sup.2中至少有一个具有手性碳原子或C-C双键或两者,当A是单个共价键时,R.sup.1和R.sup.2中至少有一个具有C-C双键。 描述了它们的制备,含有这些化合物的液晶混合物以及它们用于电光目的的用途。