Liquid crystal displays and liquid crystalline media with homeotropic alignment

A compound of formula I

• R1-A1-(Z2-A2)m1-R2 (I)
• in which:
• R2 denotes a group of the formula (A2)
• in which
• Sp denotes a spacer group or a single bond,
• X1 denotes a group —NH2, —NHR11, —NR112, —OH, —(CO)OH or a group of the formula
• R0 denotes H or alkyl having 1 to 12 C atoms,
• X2 in each case independently denotes —NH—, —NR11—, —O— or a single bond,
• R11 in each case independently denotes a halogenated or unsubstituted alkyl radical having 1 to 15 C atoms, where, in addition, one or more CH2 groups in this radical may each be replaced, independently of one another, by —C≡C—, —CH═CH—, —(CO)O—, —O(CO)—, —(CO)— or —O— in such a way that O atoms are not linked directly to one another, and where two radicals R11 may be linked to one another to form a ring,
• R12 denotes H, F, Cl, CN, —OH, —NH2, or a halogenated or unsubstituted alkyl radical having 1 to 15 C atoms, where, in addition, one or more CH2 groups in this radical may each be replaced, independently of one another, by —C≡C—, —CH═CH—, —(CO)O—, —O(CO)—, —(CO)—, —O—, —NH— or —NR1— in such a way that O and N atoms are not linked directly to one another, and
• n denotes 2 or 3,
• A1 and A2 each, independently of one another, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group, which may also contain fused rings, and which may also be mono- or polysubstituted by a group L,
• L in each case, independently of one another, denotes —OH, —(CH2)n1—OH, F, Cl, Br, I, —CN, —NO2, —NCO, —NCS, —OCN, —SCN, —C(═O)N(R0)2, —C(═O)R0, —N(R0)2, —(CH2)n1—N(R0)2, optionally substituted silyl, optionally substituted aryl or alicyclyl having 6 to 20 C atoms, or straight-chain or branched optionally unsaturated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which, in addition, one or more H atoms may be replaced by F or Cl,
• Z2 in each case, independently of one another, denotes a single bond, —O—, —S—, —CO—, —CO—O—, —OCO—, —O—CO—O—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CF2O—, —OCF2—, —CF2S—, —SCF2—, —(CH2)n1—, —CF2CH2—, —CH2CF2—, —(CF2)n1—, —CH═CH—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or CR0R00,
• R0 and R00 each, independently of one another, denote H or alkyl having 1 to 12 C atoms,
• R1 denotes H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH2 groups may be replaced by —NR2, —NR—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F or Cl,
• m1 denotes 0, 1, 2, 3 or 4, and
• n1 denotes 1, 2, 3 or 4,
• and the compound of formula I contains one or more polymerizable acrylate or methacrylate groups.

A compound of formula I

• R1-A1-(Z2-A2)m1-R2 (I)
• in which:
• R2 denotes a group of the formula (A1)
• -Sp-[X2—Z3—]kX1 (A1)
• in which
• Sp denotes a spacer group,
• X1 denotes a group —NH2, —NHR11, —NR112, —OH, —(CO)OH or a group of the formula
• R0 denotes H or alkyl having 1 to 12 C atoms,
• X2 in each case independently denotes —NH—, —NR11—, —O— or a single bond,
• Z3 in each case independently denotes an alkylene group having 1-15 C atoms, carbocyclic rings having 5 or 6 C atoms, or combinations of one or more rings and alkylene groups, in each of which hydrogen may be replaced by —OH, —OR11, —(CO)OH, —NH2, —NHR11, —NR112 or halogen,
• R11 in each case independently denotes a halogenated or unsubstituted alkyl radical having 1 to 15 C atoms, where, in addition, one or more CH2 groups in this radical may each be replaced, independently of one another, by —C≡C—, —CH═CH—, —(CO)O—, —O(CO)—, —(CO)— or —O— in such a way that O atoms are not linked directly to one another, and where two radicals R11 may be linked to one another to form a ring,
• k denotes 1, 2 or 3,
• A1 and A2 each, independently of one another, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group, which may also contain fused rings, and which may also be mono- or polysubstituted by a group L,
• L in each case, independently of one another, denotes —OH, —(CH2)n1—OH, F, Cl, Br, I, —CN, —NO2, —NCO, —NCS, —OCN, —SCN, —C(═O)N(R0)2, —C(═O)R0, —N(R0)2, —(CH2)n1—N(R0)2, optionally substituted silyl, optionally substituted aryl or alicyclyl having 6 to 20 C atoms, or straight-chain or branched optionally unsaturated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which, in addition, one or more H atoms may be replaced by F or Cl,
• Z2 in each case, independently of one another, denotes a single bond, —O—, —S—, —CO—, —CO—O—, —OCO—, —O—CO—O—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CF2O—, —OCF2—, —CF2S—, —SCF2—, —(CH2)n1—, —CF2CH2—, —CH2CF2—, —(CF2)n1—, —CH═CH—, —CF═CF—, —C≡C—, —CH═CH—COO—, —OCO—CH═CH— or CR0R00,
• R0 and R00 each, independently of one another, denote H or alkyl having 1 to 12 C atoms,
• R1 denotes H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH2 groups may be replaced by —NR2, —NR—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F or Cl,
• m1 denotes 0, 1, 2, 3 or 4
• n1 denotes 1, 2, 3 or 4,
• and the compound of formula I contains one or more polymerizable acrylate or methacrylate groups.

A LC medium with negative dielectric anisotropy, said medium comprising a low-molecular-weight liquid-crystalline component and one or more organic compounds, where the organic compound contains at least one polar anchor group and at least one ring group, wherein the polar anchor group of the organic compound contains at least one OH structure or an N atom in a primary or secondary or tertiary amino group, and wherein the anchor group is not comprised of a OH group which is a screened OH group as in 2,6-di-tert-butylphenol wherein the organic compound encompasses a compound of the formula I:

• R1-A1-(Z2-A2)m1-R2 (I)
• in which
• A1 and A2 each, independently of one another, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group, which may also contain fused rings, and which may also be mono- or polysubstituted by a group L,
• L in each case, independently of one another, denotes —OH, —(CH2)n1—OH, F, Cl, Br, I, —CN, —NO2, —NCO, —NCS, —OCN, —SCN, —C(═O)N(R0)2, —C(═O)R0, —N(R0)2, —(CH2)n1—N(R0)2, optionally substituted silyl, optionally substituted aryl or cycloalkyl having 6 to 20 C atoms, or straight-chain or branched alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 25 C atoms, in which, in addition, one or more H atoms may be replaced by F or Cl,
• Z2 is a single bond,
• R0 and R00 each, independently of one another, denote H or alkyl having 1 to 12 C atoms,
• R1, R2, independently of one another, denote H, halogen, straight-chain, branched or cyclic alkyl having 1 to 25 C atoms, in which, in addition, one or more non-adjacent CH2 groups may be replaced by —NR0—, —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O— in such a way that N, O and/or S atoms are not linked directly to one another, and in which, in addition, one or more tertiary carbon atoms (CH groups) may be replaced by N, and in which, in addition, one or more H atoms may be replaced by F or Cl,
• with the proviso that at least the radical R2 contains one or more heteroatoms selected from N, S and/or O,
• m1 denotes 0, 1, 2, 3, 4 or 5, and
• n1 denotes 1, 2, 3 or 4.