Optically active compounds, and a liquid-crystalline phase

Abstract

The invention relates to optically active compounds of the formula I ##STR1## in which R is an alkyl or alkenyl radical having up to 15 carbon atoms which is unsubstituted, monosubstituted by --CN or at least monosubstituted by fluorine or chlorine, it also being possible for a CH.sub.2 group in these radicals to be replaced by --O--, --CO--, --O--CO--, --CO--O-- or --O--CO--O--, A.sup.1 and A.sup.2 are each, independently of one another, a 1,4-phenylene radical, pyridine-2,5-diyl radical, pyrimidine-2,5-diyl radical, pyrazine-2,5-diyl radical, pyridazine-3,6-diyl radical, 1,3,4-thiadiazole-2,5-diyl radical, 1,2,4-thiadiazole-3,5-diyl radical or trans-1,4-cyclohexylene radical, each of which is unsubstituted or substituted by one or two fluorine atoms, and in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O-- and/or --S--, and/or a CH group, Z.sup.1, Z.sup.2 and Z.sup.3 are each, independently of one another, --CO--O--, --O--CO--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C-- or a single bond, Q.sup.1 is --CH.sub.2 CH.sub.2 --, --CH.sub.2 CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 OCH.sub.2 --, --OCH.sub.2 CH.sub.2 --, --O--CO-- or --CO--OCH.sub.2 --, Q.sup.2 is --O--, --O--CO--, --(CH.sub.2).sub.3 --)-- or a single bond, m is 0, 1, 2 or 3, n is 0 or 1, and o is 1 to 9, and the use thereof as components of liquid-crystalline phases.

Dependencies are inferred from the claim text.