摘要:
A process for preparing substituted 4-methylidenecinnamic acid derivatives of Formula (I). ##STR1## The variables are defined herein. The compounds of Formula (I) can be used, for example, as UV absorbers.
摘要:
The invention relates to a process for the preparation of cinnamic acid derivatives which involves reacting chlorinated aromatic compounds and acrylic acid derivatives in the presence of palladium catalysts.
摘要:
Aldehydes containing a difluorooxymethylene bridge, of the general formula I OHC-(A11)m-Z11-(A12-Z12)n-(A13-Z13)p-A14I and the use and preparation thereof and the preparation of 1,3-dioxane compounds.
摘要:
The invention relates to an electrooptical liquid-crystal display having a realignment layer for realigning the liquid crystals, where the field thereof has a significant component parallel to the liquid-crystal layer, containing a liquid-crystalline medium having positive dielectric anisotropy, where the medium comprises at least one mesogenic compound which contains a group of the formula I and at least one compound of formula II wherein L1 is H or F; R1 R2 are H, an alkyl or alkenyl radical having 1 to 15 carbon atoms which may be substituted; Q is a radical of the formula —(O)q (CH2)r—(CF2)s— in which q is 0 or 1; r is 0 or an integer of 1 to 6, and s is an integer of 0 to 6; X is F or Cl, and in the case where s ≠0, is alternatively H, and A1 and A2 are each, independently of one another, a 1,4-cyclohexenylene or trans-1,4-cyclohexylene which may be substituted; 1,4-phenylene in which may be substituted, 1,4-bicyclo[2.2.2]octylene, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4 tetrahydronaphthalene-2,6-diyl, which may be substituted; L2 and L3 are each, independently of one another, H or F; Z1 and Z2 are each, independently of one another, —CO—O—, —O—CO—, —CH2O—, —OCH2—, —CH2CH2—, —CH═CH—, —C≡C— or a single bond, or one of the radicals Z1 and Z2 is alternatively —(CH2)4— or —CH═CH—CH2CH2—, and m is 0, 1 or 2.
摘要:
The invention relates to difluorovinyl ethers of the general formula I ##STR1## in which R, A, X and m are as defined in claim 1, and to the use of these compounds as components of liquid-crystalline media, and to liquid-crystal and electro-optical display elements which contain the novel liquid-crystalline media.
摘要:
Disclosed are trifluoromethylcyclohexane derivatives of the formula I ##STR1## whereinR is an alkyl or alkenyl radical having up to 18 C atoms which is unsubstituted or substituted by CN or by at least one halogen, and in which one or more non-adjacent CH.sub.2 groups may be replaced by a radical selected from the group comprising --O--, --S--, --CO--, --O--CO--, --CO--O-- and --C.tbd.C--,A.sup.1 and A.sup.2 are each, independently of one another,a) a 1,4-phenylene radical, in which one or two CH groups may be replaced by N,b) a 1,4-cyclohexylene radical, in which one or two non-adjacent CH.sub.2 groups may be replaced by --O-- or --S--,c) a 1,4-cyclohexenylene, piperidine-1,4-diyl, 1,4-bicyclo[2,2,2]-octylene or naphthalene-2,6-diyl radical,it being possible for the radicals a) and b) to be monosubstituted or polysubstituted by halogen atoms or cyano and/or methyl groups, ##STR2## Z.sup.1 and Z.sup.2 are each, independently of one another, --CO--O--, --O--CH--, --CH.sub.2 CH.sub.2 --, --CH(CN)--CH.sub.2 --, --CH.sub.2 --CH(CN)--, --CH.dbd.CH--, --OCH .sub.2 --, --CH.sub.2 O--, --CH.dbd.N--, --N.dbd.CH--, --NO.dbd.N--, --N.dbd.NO--, --N.dbd.N-- or a single bond, ando is 0, 1 or 2.These compounds can be used as components of liquid-crystalline media for electrooptical display elements, in particular for matrix liquid-crystal displays.
摘要:
The invention relates to fluorophenylpyridines of the formula I: ##STR1## where R.sup.1 and R.sup.2 are substituted and unsubstituted monovalent organic radicals.
摘要:
The invention relates to an electro-optical liquid-crystal display having a realignment layer for realigning the liquid crystals whose field has a significant component parallel to the liquid-crystal layer and which contains a liquid-crystalline medium of positive dielectric anisotropy, where the medium comprises at least one mesogenic compound containing a 3,4,5-trifluorophenyl group and/or comprises at least one mesogenic compound [lacuna] a structural unit of the formula 2 ##STR1## in which A is O or CH,Z is --COO-- or a single bondL.sup.1 is F or, if A is O, is alternatively H, andL.sup.2 is H or F.
摘要:
The invention relates to an electro-optical liquid-crystal display having a realignment layer for realigning the liquid crystals whose field has a significant component parallel to the liquid-crystal layer and which contains a liquid-crystalline medium of positive dielectric anisotropy, where the medium comprises at least one mesogenic compound containing a 3,4,5-trifluorophenyl group and/or comprises at least one mesogenic compound [lacuna] a structural unit of the formula 2 ##STR1## in which A is O or CH,z is --COO-- or a single bondL.sup.1 is F or, if A is O, is alternatively H, andL.sup.2 is H or F.
摘要:
The invention relates to fluorophenylpyrimidines of the formula I: ##STR1## where R.sup.1, R.sup.2, A.sup.1,A.sup.2, Q.sup.1, Q.sup.2 and n have the meaning specified in patent claim 1, and to their use as components of liquid-crystalline, in particular ferroelectric, media.