Fluorinated aromatic compounds

Abstract

The present invention relates to aromatic isothiocyanates of the formula U as defined in claim 1; to liquid crystal media comprising one or more compounds of the formula U and to high-frequency components comprising these media, in particular microwave components for high-frequency devices, such as devices for shifting microwave phases, tunable filters, tunable metamaterial structures and electron beam steering antennas, such as phased array antennas.

Description

[0001] The present invention relates to fluorinated aromatic compounds, liquid crystal compounds containing the same, and to high-frequency components containing these media, especially microwave components for high-frequency devices, such as devices for shifting microwave phases, tunable filters, tunable metamaterial structures, and electronic beam steering antennas (e.g., phased array antennas), and to the devices.

[0002] Liquid-crystalline media have been used for many years in electro-optical displays (liquid crystal displays: LCD) for displaying information. Recently, however, the use of liquid-crystalline media in components for microwave technology has also been proposed, for example in DE 10 2004 029 429.1 A and JP 2005-120208 (A).

[0003] A. Gaebler, F. Goelden, S. Müller, A. Penirschke and R. Jakoby "Direct Simulation of Material Permittivites using an Eigen-Susceptibility Formulation of the Vector Variational Approach", 12MTC 2009 - International Instrumentation and Measurement Technology Conference, Singapore, 2009 (IEEE), pp. 463-467 describe the corresponding properties of the known liquid crystal mixture E7 (Merck KGaA, Germany).

[0004] DE 10 2004 029 429 A describes the use of liquid-crystalline media in microwave technology, in particular in phase shifters. The properties of the liquid-crystalline media in the corresponding frequency range are discussed and liquid-crystalline media based on mixtures of mostly aromatic nitriles and isothiocyanates are presented.

[0005] In EP 2 982 730 A1, mixtures are described which consist entirely of isothiocyanate compounds.

[0006] Fluorine atoms are often used in mesogenic compounds to introduce polarity. Especially in combination with terminal NCS groups, high dielectric anisotropy values ​​can be achieved, in particular when the NCS group at position 1 has two fluorine atoms at its ortho positions, since the total molecular dipole is the sum of all the individual dipoles of the partial structures of the molecule. A well-balanced compromise has to be found with regard to the number of fluorine atoms, since fluorine substitution often has a negative impact on the nematic properties of the compound.

[0007] Liquid crystal compositions that can be used for microwave applications still have several disadvantages. There is a need to improve these media with respect to their general physical properties, shelf life and their operational stability in devices. In view of the many different parameters that must be considered and improved in developing liquid crystal media for microwave applications, it is desirable to have a wider range of possible mixing components for developing such liquid crystal media.

[0008] It is an object of the present invention to provide compounds for liquid-crystalline media which have improved properties with regard to use in the microwave range of the electromagnetic spectrum.

[0009] In order to solve this problem, a compound of formula U shown below and a liquid crystal medium comprising the compound are provided.

[0010] The present invention relates to a compound of formula U

[0011]

[0012] in

[0013] R U represents H, alkyl or alkoxy having 1 to 12 C atoms or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, wherein one or more CH 2 - The group can be Replacement, or represents the group R P ,

[0014] R P Indicates halogen, CN, NCS, R F , R F -O- or R F -S-, where

[0015] R F represents a fluorinated alkyl or fluorinated alkenyl group having up to 9 C atoms,

[0016] Z U1 , Z U2 , Z U3 identically or differently represent -CH=CH-, -CF=CF-, -CH=CF-, -CF=CH-, -C≡C- or a single bond, preferably represent -C≡C- or a single bond,

[0017] X 1 , X 2 Identical or different representations of H, Cl, F, CH 3 or C 2 H 5 , preferably represents H or F,

[0018] Y 1 , Y 2 , Y3 , Y 4 represents, identically or differently, H, F, Cl or a linear, branched or cyclic alkyl, alkenyl, alkoxy or alkenyloxy radical, each of which has up to 12 C atoms, wherein Y 1 , Y 2 , Y 3 and Y 4 At least one of is different from F,

[0019] s is 0, 1 or 2, preferably 0 or 1,

[0020] t is 0, 1 or 2, preferably 0 or 1, and

[0021] s+t is 0, 1 or 2, preferably 0 or 1,

[0022] and

[0023] represents a group selected from the following group:

[0024] a) the group consisting of 1,4-phenylene, 1,4-naphthylene and 2,6-naphthylene, in which one or two CH groups may be replaced by N and in which one or more H atoms may be replaced by L,

[0025] b) the group consisting of: trans-1,4-cyclohexylene, 1,4-cyclohexenylene, bicyclo[1.1.1]pentane-1,3-diyl, 4,4′-bicyclohexylene, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, wherein one or more non-adjacent CH 2 The group may be replaced by -O- and / or -S- and one or more H atoms may be replaced by F,

[0026] c) the group consisting of: thiophene-2,5-diyl, thieno[3,2-b]thiophene-2,5-diyl, selenophene-2,5-diyl, each of which may also be mono- or polysubstituted by L,

[0027] L, in each occurrence, represents F, Cl, CN, SCN, SF, the same or different 5 or straight-chain or branched, in each case optionally fluorinated, alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms.

[0028] The present invention further relates to a compound of formula UN

[0029]

[0030] in which the radicals and parameters have the meanings given above for formula U.

[0031] According to another aspect of the present invention, there is provided a method for synthesizing a compound of formula U from a compound of formula UN as given below.

[0032] The present invention further relates to a liquid-crystalline medium comprising a compound of the formula U and to the use of a liquid-crystalline medium comprising a compound of the formula U in components for high-frequency technology.

[0033] According to yet another aspect of the invention, there is provided a component and a device comprising the component, both operable in the microwave region of the electromagnetic spectrum. Preferred components are phase shifters, varactor diodes, wireless and radio wave antenna arrays, matching circuits and tunable filters.

[0034] Preferred embodiments of the invention are the subject matter of the dependent claims or can be taken from the description.

[0035] Surprisingly, it has been found that liquid-crystalline media having excellent stability and at the same time high dielectric anisotropy, appropriately fast switching times, a suitable nematic phase range, high tunability and low dielectric losses can be obtained by using compounds of the formula U in liquid-crystalline media. In particular, the use of compounds of the formula U makes it possible to reduce the dielectric losses of the liquid-crystalline media while having no or only negligible negative effects on other relevant parameters such as, in particular, the nematic phase range, the dielectric anisotropy or the tunability.

[0036] The media of the present invention are characterized by a high brightness temperature, a wide nematic phase range, and excellent low temperature stability (LTS). Therefore, devices containing the media can be operated under extreme temperature conditions.

[0037] The medium is further characterized by a high dielectric anisotropy value and a low rotational viscosity. As a result, the threshold voltage is very low, i.e. the minimum voltage at which the device can be switched is very low. Low operating voltage and low threshold voltage are required to enable the device to have improved switching characteristics and high energy efficiency. Low rotational viscosity enables the device of the invention to switch quickly.

[0038] These properties overall make the medium particularly suitable for components and devices in high-frequency technology and for applications in the microwave range, in particular devices for shifting microwave phases, tunable filters, tunable metamaterial structures and electron beam steering antennas (e.g. phased array antennas).

[0039] In this context, “high-frequency technology” means the use of electromagnetic radiation with a frequency in the range of 1 MHz to 1 THz, preferably 1 GHz to 500 GHz, more preferably 2 GHz to 300 GHz, particularly preferably about 5 GHz to 150 GHz.

[0040] As used herein, halogen is F, Cl, Br or I, preferably F or Cl, and especially preferably F.

[0041] In this context, alkyl is straight-chain or branched or cyclic and has 1 to 15 C atoms, is preferably straight-chain and, unless specified otherwise, has 1, 2, 3, 4, 5, 6 or 7 C atoms, and is correspondingly preferably methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl or n-heptyl.

[0042] In this context, the branched alkyl group is preferably isopropyl, sec-butyl, isobutyl, isopentyl, 2-methylhexyl or 2-ethylhexyl.

[0043] As used herein, cyclic alkyl means a straight-chain or branched alkyl or alkenyl group having up to 12 C atoms, preferably an alkyl group having 1 to 7 C atoms, wherein the group CH 2 Replacement by a carbocyclic ring having 3 to 5 C atoms is very preferably selected from the group consisting of cyclopropylalkyl, cyclobutylalkyl, cyclopentylalkyl and cyclopentenylalkyl.

[0044] In this context, alkoxy is straight-chain or branched and contains 1 to 15 C atoms. It is preferably straight-chain and, unless otherwise specified, has 1, 2, 3, 4, 5, 6 or 7 C atoms and is correspondingly preferably methoxy, ethoxy, n-propoxy, n-butoxy, n-pentoxy, n-hexoxy or n-heptoxy.

[0045] In this article, alkenyl is preferably an alkenyl with 2 to 15 C atoms, which is straight or branched and contains at least one C-C double bond. It is preferably straight chain and has 2 to 7 C atoms. Accordingly, it is preferably vinyl; prop-1- or -2-enyl; but-1-, -2- or -3-enyl; pent-1-, -2-, -3- or -4-enyl; hex-1-, -2-, -3-, -4- or -5-enyl; hept-1-, -2-, -3-, -4-, -5- or -6-enyl. If two C atoms of the C-C double bond are substituted, the alkenyl may be in the form of E and / or Z isomers (trans / cis). In general, the corresponding E isomer is preferred. Among alkenyl, prop-2-enyl, but-2- and -3-enyl and pent-3- and -4-enyl are particularly preferred.

[0046] In this context, alkynyl is understood to mean an alkynyl radical having 2 to 15 C atoms, which is straight-chain or branched and contains at least one C—C triple bond. 1- and 2-propynyl and 1-, 2- and 3-butynyl are preferred.

[0047] If R F represents a halogenated alkyl-, alkoxy-, alkenyl or alkenyloxy radical, which may be branched or unbranched. Preferably, it is unbranched, mono-, poly- or perfluorinated, more preferably perfluorinated and has 1, 2, 3, 4, 5, 6 or 7 C atoms, in the case of alkenyl, 2, 3, 4, 5, 6 or 7 C atoms.

[0048] R P Preferably, it represents CN, NCS, Cl, F, -(CH 2 ) n -CH=CF 2 、-(CH 2 ) n -CH=CHF, -(CH 2 ) n -CH=Cl 2 , -C n F 2n+1 ,-(CF 2 ) n -CF 2 H, -(CH 2 ) n -CF 3 、-(CH 2 ) n -CHF 2 、-(CH 2 ) n CH 2 F, -CH=CF 2 、-O(CH 2 ) n -CH=CF 2 、-O(CH 2 ) n CHCl 2 、-OC n F 2n+1 、-O(CF 2 ) n -CF 2 H、-O(CH 2 ) n CF 3 、-O(CH 2 ) n -CHF 2 、-O(CF) n CH 2 F, -OCF=CF 2 , -SC n F 2n+1 、-S(CF) n -CF 3 , where n is an integer from 0 to 7.

[0049] The compounds of the general formula U are prepared by methods known per se, specifically under reaction conditions known and suitable for these reactions, as described in the literature (for example in standard works such as Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart). Variants known per se but not mentioned in greater detail here can be used.

[0050] If desired, the starting materials can also be formed in situ by not isolating them from the reaction mixture, but immediately converting them further into the compound of the general formula U.

[0051] Preferred synthetic routes to the compounds of the invention are detailed in the schemes below and are further illustrated with the aid of working examples.

[0052] A preferred intermediate is 5-bromo-1,3-difluoro-2-alkyl-benzene, which can be reacted, for example, by cross-coupling reactions commonly known as Suzuki, Stille, Sonogashira reactions and similar reactions to produce compounds of formula UN. Preferred routes are detailed in Schemes 1 and 2, wherein the radicals and parameters have the meanings defined in claim 1.

[0053]

[0054] Preferred reagents for the process of the invention for converting compounds of formula UN into compounds of formula U (Scheme 3) are carbon disulfide, thiophosgene, thiocarbonyldiimidazole, di-2-pyridylthiocarbonate, bis(dimethylthiocarbamoyl)disulfide, dimethylaminothiocarbonyl chloride and phenylchlorothioformate, very preferably thiophosgene.

[0055]

[0056] The reactions described should be regarded as illustrative only. A person skilled in the art can carry out corresponding variations of the described synthesis and also follow other suitable synthetic routes to obtain compounds of formula U.

[0057] The compound of formula U is preferably selected from the following compounds, wherein the group and

[0058] Same or different

[0059] One or both CH-groups may be replaced by N, and wherein Alternatively, and

[0060] L 1 and L 2 represents, identically or differently, F, Cl or a linear or branched or cyclic alkyl or alkenyl radical each having up to 12 C atoms, and

[0061] wherein the other radicals and parameters have the meanings given above.

[0062] In a preferred embodiment of the invention, the compound of formula U is selected from the compounds of formulae U-1 to U-20, very preferably from the compounds of formulae U-1 to U13:

[0063]

[0064]

[0065]

[0066] The radicals occurring therein have the meanings specified above for formula U and its subformulae, and preferably, R U represents an alkyl group having 1 to 7 C atoms, Y 1 , Y 2 , Y 3 and Y 4 represents H, F, Cl, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclopentenyl, identically or differently, and more preferably, Y 1 and Y 2 independently represents H or F, especially represents H, and Y 3 and Y 4 Very preferably represents H, and L 1 and L 2 Identically or differently very preferably represents H, F, methyl or ethyl, in particular represents H.

[0067] According to one embodiment of the present invention, there is provided a compound of formula U, wherein R U represents H, alkyl or alkoxy having 1 to 12 C atoms or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, wherein one or more CH 2 - The group can be Instead, preference is given to alkyl having 1 to 12 C atoms.

[0068] According to another embodiment of the present invention, there is provided a compound of formula U, wherein the group R U Represents R P , where R PIndicates halogen, CN, NCS, R F , R F -O- or R F -S-, and R F represents a fluorinated alkyl or fluorinated alkenyl group having up to 9 C atoms, preferably CF 3 or OCF 3 .

[0069] In a preferred embodiment of the invention, the medium comprises one or more compounds selected from the group of compounds of formulae I, II and III,

[0070]

[0071] in

[0072] R 1 represents H; an unfluorinated alkyl or unfluorinated alkoxy radical having 1 to 17, preferably 3 to 10, C atoms; or an unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl radical having 2 to 15, preferably 3 to 10, C atoms; wherein one or more CH 2 - The group can be Instead, preferably an unfluorinated alkyl or unfluorinated alkenyl group,

[0073] n is 0, 1, or 2,

[0074] to

[0075] At each occurrence, they are expressed independently of each other

[0076]

[0077] Where R L represents, identically or differently on each occurrence, H or alkyl having 1 to 6 C atoms, preferably H, methyl or ethyl, particularly preferably H, and in which

[0078]

[0079] Alternatively,

[0080]

[0081] Best

[0082]

[0083] And when n=2, One of the preferred representations and the other preferably represents

[0084]

[0085] And preferably

[0086] to

[0087] Independently express

[0088]

[0089]

[0090] More preferred

[0091] express

[0092] express

[0093] express

[0094] R 2 represents H; an unfluorinated alkyl or unfluorinated alkoxy radical having 1 to 17, preferably 3 to 10, C atoms; or an unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl radical having 2 to 15, preferably 3 to 10, C atoms; wherein one or more CH 2 - The group can be Instead,

[0095] Preferably it is an unfluorinated alkyl group or an unfluorinated alkenyl group,

[0096] Z 21 represents trans-CH=CH-, trans-CF=CF- or -C≡C-, preferably -C≡C- or trans-CH=CH-, and

[0097] and

[0098] Independently express

[0099]

[0100] Where R L represents, identically or differently on each occurrence, H or alkyl having 1 to 6 C atoms, preferably H, methyl or ethyl, particularly preferably H, and wherein

[0101] Alternatively,

[0102] Best

[0103] and

[0104] Independently express

[0105]

[0106]

[0107] Preferred representation

[0108]

[0109] and

[0110]

[0111] Preferred representation

[0112]

[0113] More preferred

[0114]

[0115] R 3 represents H; an unfluorinated alkyl or unfluorinated alkoxy radical having 1 to 17, preferably 3 to 10, C atoms; or an unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl radical having 2 to 15, preferably 3 to 10, C atoms; wherein one or more CH 2 - The group can be Instead,

[0116] Preferably it is an unfluorinated alkyl group or an unfluorinated alkenyl group,

[0117] Z 31 and Z 32 One of them is preferably Z 32 represents trans-CH=CH-, trans-CF=CF- or -C≡C-, and the other of them independently represents -C≡C-, trans-CH=CH-, trans-CF=CF- or a single bond, preferably one of them, preferably Z 32 represents -C≡C- or trans-CH=CH- and the other represents a single bond, and

[0118] to

[0119] Independently express

[0120]

[0121] Where R L represents, identically or differently on each occurrence, H or alkyl having 1 to 6 C atoms, preferably H, methyl or ethyl, particularly preferably H, and wherein

[0122]

[0123] Alternatively,

[0124]

[0125] Alternatively,

[0126] Best

[0127] to

[0128] Independently express

[0129]

[0130]

[0131] More preferred

[0132] express

[0133]

[0134] express

[0135] in particular

[0136] express

[0137] in particular

[0138] In the compounds of formula I, II and III, R L Preferably it represents H.

[0139] In another preferred embodiment, in the compounds of the formulae I, II and III, one or two radicals R L , preferably a group R L Different from H.

[0140] In a preferred embodiment of the present invention, the compound of formula I is selected from the compounds of formula I-1 to I-5:

[0141]

[0142] in

[0143] L 1 , L 2 and L 3 In each occurrence, it may represent H or F in the same or different manner,

[0144] and the other groups have the corresponding meanings and preferences shown above for formula I

[0145] R 1 represents a non-fluorinated alkyl group having 1 to 7 C atoms or a non-fluorinated alkenyl group having 2 to 7 C atoms.

[0146] The medium preferably comprises one or more compounds of formula I-1, which are preferably selected from the compounds of formulae I-1a to I-1d, preferably compounds of formula I-1b:

[0147]

[0148]

[0149] Where R 1 has the meanings given above for formula I and preferably represents unfluorinated alkyl having 1 to 7 C atoms or unfluorinated alkenyl having 2 to 7 C atoms.

[0150] The medium preferably comprises one or more compounds of formula I-2, which are preferably selected from the compounds of formulae I-2a to I-2e, preferably compounds of formula I-2c:

[0151]

[0152]

[0153] Where R 1 has the meanings given above for formula I and preferably represents unfluorinated alkyl having 1 to 7 C atoms or unfluorinated alkenyl having 2 to 7 C atoms.

[0154] The medium preferably comprises one or more compounds of the formula I-3, which are preferably selected from the compounds of the formulae I-3a to I-3d, particularly preferably compounds of the formula I-3b:

[0155]

[0156] Where R 1has the meanings given above for formula I and preferably represents unfluorinated alkyl having 1 to 7 C atoms or unfluorinated alkenyl having 2 to 7 C atoms.

[0157] The medium preferably comprises one or more compounds of the formula I-4, which are preferably selected from the compounds of the formulae I-4a to I-4e, particularly preferably compounds of the formula I-4b:

[0158]

[0159]

[0160] Where R 1 has the meanings given above for formula I and preferably represents unfluorinated alkyl having 1 to 7 C atoms or unfluorinated alkenyl having 2 to 7 C atoms.

[0161] The medium preferably contains one or more compounds of the formula I-5, which are preferably selected from the compounds of the formulae I-5a to I-5d, particularly preferably compounds of the formula I-5b:

[0162]

[0163]

[0164] Where R 1 has the meanings given above for formula I and preferably represents unfluorinated alkyl having 1 to 7 C atoms or unfluorinated alkenyl having 2 to 7 C atoms.

[0165] The medium preferably comprises one or more compounds of formula II, which are preferably selected from compounds of formulae II-1 to II-3, preferably selected from compounds of formulae II-1 and II-2:

[0166]

[0167] The radicals occurring therein have the meanings and preferences given above under formula II

[0168] R 2 represents H, a non-fluorinated alkyl or alkoxy radical having 1 to 7 C atoms or a non-fluorinated alkenyl radical having 2 to 7 C atoms,

[0169] and

[0170] and One of them said

[0171]

[0172] and the other independently expresses

[0173]

[0174] Best

[0175]

[0176] Best choice

[0177]

[0178] and preferred

[0179] R 2 Represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0180] n represents an integer ranging from 1 to 15, preferably an integer ranging from 1 to 7 and particularly preferably an integer from 1 to 5, and

[0181] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0182] The compound of formula II-1 is preferably selected from the compounds of formula II-1a to II-1e:

[0183]

[0184]

[0185] in

[0186] R 2 Has the above meaning and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0187] n independently of one another represents an integer ranging from 1 to 15, preferably an integer ranging from 1 to 7 and particularly preferably an integer from 1 to 5, and

[0188] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0189] The compound of formula II-2 is preferably selected from compounds of formula II-2a and II-2b:

[0190]

[0191] in

[0192] R 2 Has the above meaning and preferably represents C n H 2n+1 or CH2 =CH-(CH 2 ) Z ,

[0193] n represents an integer ranging from 1 to 15, preferably an integer ranging from 1 to 7 and particularly preferably an integer from 1 to 5, and

[0194] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0195] The compound of formula II-3 is preferably selected from the compounds of formula II-3a to II-3d:

[0196]

[0197] in

[0198] R 2 Has the above meaning and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,

[0199] n represents an integer ranging from 1 to 15, preferably an integer ranging from 1 to 7 and particularly preferably an integer from 1 to 5, and

[0200] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0201] The compound of formula III is preferably selected from the compounds of formula III-1 to III-6, more preferably selected from the compounds of formula III-1, III-2, III-3 and III-4, and particularly preferably the compound of formula III-1:

[0202]

[0203]

[0204] in

[0205] Where Z 31 and Z 32 represents trans-CH=CH- or trans-CF=CF-, preferably trans-CH=CH-, and in formula III-6, Z 31 and Z 32 One of them may alternatively represent -C≡C- and the other groups have the meanings given above according to formula III,

[0206] And preferably

[0207] R 3is an unfluorinated alkyl or alkoxy radical having 1 to 7 C atoms or an unfluorinated alkenyl radical having 2 to 7 C atoms, and

[0208] to One, preferred express

[0209]

[0210] Best

[0211]

[0212] And the others are expressed independently of each other

[0213]

[0214] Best

[0215]

[0216] More preferred

[0217]

[0218] in

[0219] Alternatively,

[0220] And preferably

[0221] R 3 Represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,

[0222] n represents an integer in the range of 1 to 15, preferably in the range of 1 to 7 and particularly preferably in the range of 1 to 5, and

[0223] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0224] The compound of formula III-1 is preferably selected from the group of compounds of formula III-1a to III-11, more preferably selected from the group of compounds of formula III-1b, III-1f, III-1g and III-1i.

[0225]

[0226]

[0227] in

[0228] R 3 Has the above meaning and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,

[0229] n represents an integer ranging from 1 to 15, preferably an integer ranging from 1 to 7 and particularly preferably an integer from 1 to 5, and

[0230] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0231] The compound of formula III-2 is preferably a compound of formula III-2a to III-21, very preferably a compound of III-2b and / or III-2j:

[0232]

[0233]

[0234] Where R 3 Has the above meaning and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,

[0235] n represents an integer ranging from 1 to 15, preferably an integer ranging from 1 to 7 and particularly preferably an integer from 1 to 5, and

[0236] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0237] The compound of formula III-5 is preferably selected from the compound of formula III-5a:

[0238]

[0239] R 3 has the meanings and preferred representations shown above for formula III-5 n H 2n+1 ,in

[0240] n represents an integer in the range of 1-7, preferably an integer in the range of 1-5.

[0241] In a preferred embodiment, the medium according to the invention comprises one or more compounds selected from the compounds of the formulae IIA-1-1 to IIA-1-12, very preferably compounds of IIA-1-1 or IIA-1-2:

[0242]

[0243]

[0244] in

[0245] R 1 denotes an alkyl or alkenyl group having up to 7 C atoms, preferably ethyl, n-propyl, n-butyl or n-pentyl, n-hexyl,

[0246] R L represents, identically or differently on each occurrence, alkyl or alkenyl having 1 to 5 C atoms or cycloalkyl or cycloalkenyl having in each case 3 to 6 C atoms,

[0247] Preference is given to methyl, ethyl, n-propyl, n-butyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclopent-1-enyl, very preferably ethyl.

[0248] And the compound of formula II-1 is excluded therefrom.

[0249] Additionally, in certain embodiments, the liquid-crystalline media according to the present invention, which may be the same as or different from the previously preferred embodiments, preferably comprise one or more compounds of formula IV,

[0250]

[0251] in

[0252] express

[0253] s is 0 or 1, preferably 1, and

[0254] Preferably

[0255] express

[0256]

[0257] Particularly preferably

[0258]

[0259] L 4 represents H or an alkyl group having 1 to 6 C atoms, a cycloalkyl group having 3 to 6 C atoms or a cycloalkenyl group having 4 to 6 C atoms, preferably CH 3 , C 2 H 5 、nC 3 H 7 、iC 3 H7 , cyclopropyl, cyclobutyl, cyclohexyl, cyclopent-1-enyl or cyclohex-1-enyl, and particularly preferably CH 3 , C 2 H 5 , cyclopropyl or cyclobutyl,

[0260] X 4 represents H, alkyl having 1 to 3 C atoms or halogen, preferably H, F or Cl, more preferably H or F and very particularly preferably F,

[0261] R 41 To R 44 , independently of one another represent unfluorinated alkyl or unfluorinated alkoxy groups each having 1 to 15 C atoms, unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl groups each having 2 to 15 C atoms, or cycloalkyl, alkylcycloalkyl, cycloalkenyl, alkylcycloalkenyl, alkylcycloalkylalkyl or alkylcycloalkenylalkyl groups each having up to 15 C atoms, and alternatively R 43 and R 44 One or both also represent H,

[0262] Best

[0263] R 41 and R 42 , independently of one another represent a non-fluorinated alkyl or non-fluorinated alkoxy group each having 1 to 7 C atoms, or a non-fluorinated alkenyl, non-fluorinated alkenyloxy or non-fluorinated alkoxyalkyl group each having 2 to 7 C atoms,

[0264] Particularly preferably

[0265] R 41 represents a non-fluorinated alkyl group having 1 to 7 C atoms, a non-fluorinated alkenyl group, a non-fluorinated alkenyloxy group or a non-fluorinated alkoxyalkyl group each having 2 to 7 C atoms, and

[0266] Particularly preferably

[0267] R 42 represents a non-fluorinated alkyl or non-fluorinated alkoxy group each having 1 to 7 C atoms, and

[0268] Best

[0269] R 43 and R 44 represents H, unfluorinated alkyl having 1 to 5 C atoms, unfluorinated cycloalkyl or cycloalkenyl having 3 to 7 C atoms, unfluorinated alkylcyclohexyl or unfluorinated cyclohexylalkyl having 4 to 12 C atoms in each case, or unfluorinated alkylcyclohexylalkyl having 5 to 15 C atoms, particularly preferably cyclopropyl, cyclobutyl or cyclohexyl, and very particularly preferably R43 and R 44 At least one of represents n-alkyl, particularly preferably methyl, ethyl or n-propyl, and the other represents H or n-alkyl, particularly preferably H, methyl, ethyl or n-propyl.

[0270] In a preferred embodiment of the present invention, the liquid-crystalline medium additionally comprises one or more compounds selected from the group consisting of compounds of the formulae V, VI, VII, VIII and IX:

[0271]

[0272] in

[0273] L 51 Represents R 51 or X 51 ,

[0274] L 52 Represents R 52 or X 52 ,

[0275] R 51 and R 52 , independently of one another represent H, non-fluorinated alkyl or non-fluorinated alkoxy having 1-17, preferably 3-10 C atoms, or non-fluorinated alkenyl, non-fluorinated alkenyloxy or non-fluorinated alkoxyalkyl having 2-15, preferably 3-10 C atoms, preferably alkyl or non-fluorinated alkenyl,

[0276] X 51 and X 52 , independently represent H, F, Cl, -CN, SF 5 , fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms or fluorinated alkenyl, fluorinated alkenyloxy or fluorinated alkoxyalkyl having 2 to 7 C atoms, preferably fluorinated alkoxy, fluorinated alkenyloxy, F or Cl, and

[0277] to

[0278] Independently express

[0279]

[0280] Preferably

[0281]

[0282] L 61 Represents R 61 and in Z 61 and / or Z 62When trans-CH=CH- or trans-CF=CF- is represented, X is also represented alternatively. 61 ,

[0283] L 62 Represents R 62 and in Z 61 and / or Z 62 When trans-CH=CH- or trans-CF=CF- is represented, X is also represented alternatively. 62 ,

[0284] R 61 and R 62 , independently of one another represent H, non-fluorinated alkyl or non-fluorinated alkoxy having 1-17, preferably 3-10 C atoms, or non-fluorinated alkenyl, non-fluorinated alkenyloxy or non-fluorinated alkoxyalkyl having 2-15, preferably 3-10 C atoms, preferably alkyl or non-fluorinated alkenyl,

[0285] X 61 and X 62 , independently represent F or Cl, -CN, SF 5 , a fluorinated alkyl or alkoxy radical having 1 to 7 C atoms or a fluorinated alkenyl, alkenyloxy or alkoxyalkyl radical having 2 to 7 C atoms,

[0286] Z 61 and Z 62 one of them represents trans-CH=CH-, trans-CF=CF- or -C≡C- and the other independently thereof represents trans-CH=CH-, trans-CF=CF- or a single bond, preferably one of them represents -C≡C- or trans-CH=CH- and the other represents a single bond, and

[0287] to

[0288] Independently express

[0289]

[0290] Preferably

[0291]

[0292] and

[0293] x represents 0 or 1;

[0294] L 71 Represents R 71 or X 71 ,

[0295] L 72 Represents R72 or X 72 ,

[0296] R 71 and R 72 , independently of one another represent H, non-fluorinated alkyl or non-fluorinated alkoxy having 1-17, preferably 3-10 C atoms, or non-fluorinated alkenyl, non-fluorinated alkenyloxy or non-fluorinated alkoxyalkyl having 2-15, preferably 3-10 C atoms, preferably alkyl or non-fluorinated alkenyl,

[0297] X 71 and X 72 , independently represent H, F, Cl, -CN, -NCS, -SF 5 , fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms or fluorinated alkenyl, unfluorinated or fluorinated alkenyloxy or unfluorinated or fluorinated alkoxyalkyl having 2 to 7 C atoms, preferably fluorinated alkoxy, fluorinated alkenyloxy, F or Cl, and

[0298] Z 71 To Z 73 , independently represent trans-CH=CH-, trans-CF=CF-, -C≡C- or a single bond, preferably one or more of them represent a single bond, and particularly preferably all of them represent a single bond and

[0299] to

[0300] Independently express

[0301]

[0302] Preferably

[0303]

[0304] R 81 and R 82 , independently of one another represent H, non-fluorinated alkyl or alkoxy having 1-15, preferably 3-10 C atoms, or non-fluorinated alkenyl, alkenyloxy or alkoxyalkyl having 2-15, preferably 3-10 C atoms, preferably non-fluorinated alkyl or alkenyl,

[0305] Z 81 and Z 82 one of them represents trans-CH=CH-, trans-CF=CF- or -C≡C- and the other independently thereof represents trans-CH=CH-, trans-CF=CF- or a single bond, preferably one of them represents -C≡C- or trans-CH=CH- and the other represents a single bond, and

[0306] express

[0307]

[0308] Independently express

[0309]

[0310] L 91 Represents R 91 or X 91 ,

[0311] L 92 Represents R 92 or X 92 ,

[0312] R 91 and R 92 , independently of one another represent H, non-fluorinated alkyl or alkoxy having 1-15, preferably 3-10 C atoms, or non-fluorinated alkenyl, alkenyloxy or alkoxyalkyl having 2-15, preferably 3-10 C atoms, preferably non-fluorinated alkyl or alkenyl,

[0313] X 91 and X 92 , independently represent H, F, Cl, -CN, -NCS, -SF 5 , fluorinated alkyl or fluorinated alkoxy having 1 to 7 C atoms or fluorinated alkenyl, unfluorinated or fluorinated alkenyloxy or unfluorinated or fluorinated alkoxyalkyl having 2 to 7 C atoms, preferably fluorinated alkoxy, fluorinated alkenyloxy, F or Cl, and

[0314] Z 91 To Z 93 , independently of one another represent trans-CH=CH-, trans-CF=CF-, -C≡C- or a single bond, preferably one or more of them represent a single bond, and particularly preferably all represent a single bond,

[0315] express

[0316] to

[0317] Independently express

[0318]

[0319] In a preferred embodiment of the present invention, the liquid-crystalline medium comprises one or more compounds of the formula V, preferably selected from the compounds of the formulae V-1 to V-3, preferably compounds of the formulae V-1 and / or V-2 and / or V-3, preferably compounds of the formulae V-1 and V-2:

[0320]

[0321]

[0322] The radicals occurring therein have the corresponding meanings indicated above for formula V and are preferably

[0323] R 51 represents a non-fluorinated alkyl group having 1 to 7 C atoms or a non-fluorinated alkenyl group having 2 to 7 C atoms,

[0324] R 52 represents a non-fluorinated alkyl group having 1 to 7 C atoms or a non-fluorinated alkenyl group having 2 to 7 C atoms or a non-fluorinated alkoxy group having 1 to 7 C atoms,

[0325] X 51 and X 52 , independently represent F, Cl, -OCF 3 , -CF 3 , -CN or -SF 5 , preferably F, Cl, -OCF 3 or -CN.

[0326] The compound of formula V-1 is preferably selected from the compounds of formulae V-1a to V-1d, preferably V-1c and V-1d:

[0327]

[0328] wherein the parameters have the corresponding meanings indicated above for formula V-1 and wherein Y 51 and Y 52 , independently of each other in each case represent H or F, and preferably R 51 represents an alkyl or alkenyl group, and

[0329] X 51 Indicates F, Cl or -OCF 3 .

[0330] The compound of formula V-2 is preferably selected from the compounds of formulae V-2a to V-2e and / or from the compounds of formulae V-2f and V-2g:

[0331]

[0332] wherein in each case the compound of formula V-2a is not included in the compounds of formulae V-2b and V-2c, the compound of formula V-2b is not included in the compounds of formula V-2c and the compound of formula V-2f is not included in the compounds of formula V-2g, and

[0333] wherein the parameters have the corresponding meanings indicated above for formula V-1 and wherein

[0334] Y 51 and Y 52 , independently of one another in each case represent H or F, and preferably

[0335] Y 51 and Y 52 represents H and the other represents H or F, preferably both represent H.

[0336] The compound of formula V-3 is preferably a compound of formula V-3a:

[0337]

[0338] wherein the parameters have the corresponding meanings indicated above for formula V-1 and wherein preferably

[0339] X 51 represents F, Cl, preferably F,

[0340] X 52 Indicates F, Cl or -OCF 3 , preferably -OCF 3 .

[0341] The compound of formula V-1a is preferably selected from the compounds of formula V-1a-1 and V-1a-2

[0342]

[0343] in

[0344] R 51 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0345] n represents an integer in the range of 1-7, preferably an integer in the range of 1-5 and particularly preferably 3 or 4.

[0346] The compound of formula V-1b is preferably a compound of formula V-1b-1:

[0347]

[0348] in

[0349] R 51has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0350] n represents an integer in the range of 1-15, preferably an integer in the range of 1-7 and particularly preferably an integer in the range of 1-5.

[0351] The compound of formula V-1c is preferably selected from the compounds of formula V-1c-1 to V-1c-4, particularly preferably selected from the compounds of formula V-1c-1 and V-1c-2:

[0352]

[0353] in

[0354] R 51 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0355] n represents an integer in the range of 1-15, preferably an integer in the range of 1-7 and particularly preferably an integer in the range of 1-5.

[0356] The compound of formula V-1d is preferably selected from the compounds of formula V-1d-1 and V-1d-2, and the compound of formula V-1d-2 is particularly preferred:

[0357]

[0358] in

[0359] R 51 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0360] n represents an integer in the range of 1-15, preferably an integer in the range of 1-7 and particularly preferably an integer in the range of 1-5.

[0361] The compound of formula V-2a is preferably selected from the compounds of formula V-2a-1 and V-2a-2, particularly preferably the compound of formula V-2a-1:

[0362]

[0363] in

[0364] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0365] R52 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0366] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0367] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0368] Preferred (R 51 and R 52 ), particularly in the case of formula V-2a-1, is (C n H 2n+1 and C m H 2m+1 )、(C n H 2n+1 and OC m H 2m+1 )、(CH 2 =CH-(CH 2 ) Z and C m H 2m+1 )、(CH 2 =CH-(CH 2 ) Z and OC m H 2m+1 ) and (C n H 2n+1 and (CH 2 ) Z -CH=CH 2 ).

[0369] Preferred compounds of formula V-2b are compounds of formula V-2b-1:

[0370]

[0371] in

[0372] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0373] R 52has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0374] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0375] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0376] Here (R 51 and R 52 ) is particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0377] Preferred compounds of formula V-2c are compounds of formula V-2c-1:

[0378]

[0379] in

[0380] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0381] R 52 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0382] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0383] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0384] Here (R 51 and R 52 ) is particularly preferably (C n H 2n+1and C m H 2m+1 ).

[0385] Preferred compounds of formula V-2d are compounds of formula V-2d-1:

[0386]

[0387] in

[0388] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,

[0389] and

[0390] R 52 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0391] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0392] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0393] Here (R 51 and R 52 ) is particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0394] Preferred compounds of formula V-2e are compounds of formula V-2e-1:

[0395]

[0396] in

[0397] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0398] R52 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0399] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0400] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0401] Here (R 51 and R 52 ) is particularly preferably (C n H 2n+1 and OC m H 2m+1 ).

[0402] Preferred compounds of formula V-2f are compounds of formula V-2f-1:

[0403]

[0404] in

[0405] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0406] R 52 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0407] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0408] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0409] Here (R 51 and R 52 ) Preferred combinations are especially (C nH 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0410] Preferred compounds of formula V-2g are compounds of formula V-2g-1:

[0411]

[0412] in

[0413] R 51 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0414] R 52 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0415] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0416] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0417] Here (R 51 and R 52 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and OC m H 2m+1 ).

[0418] The compound of formula VI is preferably selected from the compounds of formula VI-1 to VI-5:

[0419]

[0420]

[0421] in

[0422] Z 61 and Z 62 represents -C≡C-, trans-CH=CH- or trans-CF=CF-, preferably -C≡C- or trans-CH=CH-, and the other groups and parameters occurring have the meanings given above under formula VI,

[0423] And preferably

[0424] R 61 and R 62 , independently of one another represent H, a non-fluorinated alkyl or alkoxy group having 1 to 7 C atoms or a non-fluorinated alkenyl group having 2 to 7 C atoms,

[0425] X 62 Indicates F, Cl, -OCF 3 or -CN,

[0426] The compound of formula VI-1 is preferably selected from the compounds of formula VI-1a and VI-1b, more preferably selected from the compounds of formula VI-1a:

[0427]

[0428] in

[0429] R 61 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0430] R 62 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0431] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0432] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0433] Here (R 61 and R 62 ) is particularly preferably (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), and in the case of Formula VI-1a, (C n H 2n+1 and C m H 2m+1 ) and in the case of formula VI-1b, particularly preferably (C n H 2n+1 and OC m H 2m+1 ).

[0434] The compound of formula VI-3 is preferably selected from the compounds of formula VI-3a to VI-3e:

[0435]

[0436] wherein the parameters have the meanings given above under formula VI-3 and are preferably

[0437] R 61 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0438] n represents an integer in the range of 1 to 7, preferably an integer in the range of 1 to 5, and

[0439] X 62 Indicates -F, -Cl, -OCF 3 or -CN.

[0440] The compound of formula VI-4 is preferably selected from the compounds of formulae VI-4a to VI-4e:

[0441]

[0442]

[0443] wherein the parameters have the meanings given above under formula VI-4 and preferably

[0444] R 61 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0445] n represents an integer in the range of 1 to 7, preferably an integer in the range of 1 to 5, and

[0446] X 62 Indicates F, Cl, OCF 3 or -CN.

[0447] The compound of formula VI-5 is preferably selected from the compounds of formula VI-5a to VI-5d, preferably VI-5b

[0448]

[0449]

[0450] wherein the parameters have the meanings given above under formula VI-5 and preferably

[0451] R 61 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0452] n represents an integer in the range of 1 to 7, preferably an integer in the range of 1 to 5, and

[0453] X 62 Indicates -F, -Cl, -OCF 3 or -CN, particularly preferably -OCF 3 .

[0454] The compound of formula VII is preferably selected from the compounds of formula VII-1 to VII-6:

[0455]

[0456]

[0457] wherein the compound of formula VII-5 is not included in the compound of formula VII-6, and

[0458] wherein the parameters have the corresponding meanings indicated above for formula VII,

[0459] Y 71 , Y 72 , Y 73 independently of each other represent H or F,

[0460] and preferred

[0461] R 71 represents a non-fluorinated alkyl or alkoxy group each having 1 to 7 C atoms, or a non-fluorinated alkenyl group having 2 to 7 C atoms,

[0462] R 72represents a non-fluorinated alkyl or alkoxy group each having 1 to 7 C atoms, or a non-fluorinated alkenyl group having 2 to 7 C atoms,

[0463] X 72 Indicates F, Cl, NCS or -OCF 3 , preferably F or NCS, and

[0464] Especially preferred

[0465] R 71 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0466] R 72 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0467] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0468] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0469] The compound of formula VII-1 is preferably selected from the compounds of formula VII-1a to VII-1d:

[0470]

[0471]

[0472] Where X 72 has the meaning given above for Formula VII-2 and

[0473] R 71 has the meaning indicated above and preferably represents C n H 2n+1 ,in

[0474] n represents 1 to 7, preferably 2 to 6, particularly preferably 2, 3 or 5, and

[0475] z represents 0, 1, 2, 3 or 4, preferably 0 or 2, and

[0476] X 72 Preferably it represents F.

[0477] The compound of formula VII-2 is preferably selected from the compounds of formula VII-2a and VII-2b, and the compound of formula VII-2a is particularly preferred:

[0478]

[0479] in

[0480] R 71 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0481] R 72 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0482] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0483] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0484] Here (R 71 and R 72 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0485] The compound of formula VII-3 is preferably a compound of formula VII-3a:

[0486]

[0487] in

[0488] R 71 has the meaning indicated above and preferably represents C n H2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0489] R 72 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0490] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0491] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0492] Here (R 71 and R 72 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0493] The compound of formula VII-4 is preferably a compound of formula VII-4a:

[0494]

[0495] in

[0496] R 71 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0497] R 72 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z-CH=CH 2 , and among them

[0498] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0499] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0500] Here (R 71 and R 72 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0501] The compound of formula VII-5 is preferably selected from the compounds of formula VII-5a and VII-5b, more preferably the compound of formula VII-5a:

[0502]

[0503] in

[0504] R 71 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0505] R 72 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0506] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0507] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0508] Here (R 71 and R72 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0509] The compound of formula VII-6 is preferably selected from the compounds of formula VII-6a and VII-6b:

[0510]

[0511] in

[0512] R 71 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0513] R 72 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0514] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0515] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0516] Here (R 71 and R 72 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1).

[0517] The compound of formula VII-7 is preferably selected from the compounds of formula VII-7a to VII-7d:

[0518]

[0519] in

[0520] R 71 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,

[0521] X 72 Indicates F, -OCF 3 or -NCS,

[0522] n independently represents an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0523] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0524] The compound of formula VIII is preferably selected from the compounds of formulae VIII-1 to VIII-3, more preferably these compounds of formula VIII consist essentially of them, even more preferably consist essentially of them and very particularly preferably consist entirely of them:

[0525]

[0526] in

[0527] Y 81 and Y 82 one of them represents H and the other represents H or F, and

[0528] R 81 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0529] R 82 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0530] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0531] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0532] Here (R 81 and R 82 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0533] The compound of formula VIII-1 is preferably selected from the compounds of formula VIII-1a to VIII-1c:

[0534]

[0535]

[0536] in

[0537] R 81 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0538] R 82 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0539] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0540] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0541] Here (R 81 and R 82) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0542] The compound of formula VIII-2 is preferably a compound of formula VIII-2a:

[0543]

[0544] in

[0545] R 81 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0546] R 82 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0547] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0548] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0549] Here (R 81 and R 82 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 )、(C n H 2n+1 and OC m H 2m+1 ) and (CH 2 =CH-(CH 2 ) Z and C m H 2m+1), particularly preferably (C n H 2n+1 and C m H 2m+1 ).

[0550] The compound of formula VIII-3 is preferably a compound of formula VIII-3a:

[0551]

[0552] in

[0553] R 81 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0554] R 82 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0555] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0556] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0557] Here (R 81 and R 82 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ).

[0558] The compound of formula IX is preferably selected from the compounds of formula IX-1 to IX-3:

[0559]

[0560] wherein the parameters have the corresponding meanings indicated above under formula IX and are preferably

[0561] to One of them said

[0562]

[0563] and

[0564] in

[0565] R 91 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0566] R 92 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0567] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0568] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0569] Here (R 91 and R 92 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ).

[0570] The compound of formula IX-1 is preferably selected from the compounds of formula IX-1a to IX-1e:

[0571]

[0572]

[0573] wherein the parameters have the meanings given above and are preferably

[0574] R 91 has the meaning indicated above and preferably represents C n H 2n+1 ,and

[0575] n represents an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0576] X 92 Preferably it represents F or Cl.

[0577] The compound of formula IX-2 is preferably selected from the compounds of formula IX-2a and IX-2b:

[0578]

[0579] in

[0580] R 91 has the meaning indicated above and preferably represents C n H 2n+1 or CH 2 =CH-(CH 2 ) Z ,and

[0581] R 92 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0582] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0583] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0584] Here (R 91 and R 92 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ).

[0585] The compound of formula IX-3 is preferably a compound of formula IX-3a and IX-3b:

[0586]

[0587]

[0588] in

[0589] R 91 has the meaning indicated above and preferably represents C n H 2n+1 or CH2 =CH-(CH 2 ) Z ,and

[0590] R 92 has the meaning indicated above and preferably represents C m H 2m+1 or OC m H 2m+1 or (CH 2 ) Z -CH=CH 2 , and among them

[0591] n and m, independently of each other, represent an integer in the range of 1 to 15, preferably an integer in the range of 1 to 7 and particularly preferably an integer in the range of 1 to 5, and

[0592] z represents 0, 1, 2, 3 or 4, preferably 0 or 2.

[0593] Here (R 91 and R 92 ) Preferred combinations are especially (C n H 2n+1 and C m H 2m+1 ) and (C n H 2n+1 and OC m H 2m+1 ), particularly preferably (C n H 2n+1 and OC m H 2m+1 ).

[0594] In a preferred embodiment of the invention, the medium comprises one or more compounds of formula X

[0595]

[0596] in

[0597] R 101 represents H, alkyl or alkoxy having 1-15, preferably 3-10 C atoms, or non-fluorinated alkenyl, non-fluorinated alkenyloxy or non-fluorinated alkoxyalkyl having 2-15, preferably 3-10 C atoms, preferably alkyl or alkenyl,

[0598] X 101 Indicates H, F, Cl, -CN, SF 5 , NCS, a fluorinated alkyl or fluorinated alkoxy group having 1 to 7 C atoms or a fluorinated alkenyl, fluorinated alkenyloxy or fluorinated alkoxyalkyl group having 2 to 7 C atoms, preferably a fluorinated alkoxy group, a fluorinated alkenyloxy group, F, Cl or NCS, particularly preferably NCS,

[0599] Y 101 represents methyl, ethyl or Cl,

[0600] Y 102 represents H, methyl, ethyl, F or Cl, preferably H or F,

[0601] Z 101 ,Z 102 represents, identically or differently, a single bond, -CH=CH-, -CF=CF- or -C≡C-,

[0602] Independently express

[0603]

[0604] Preferably

[0605] and which alternatively represents and

[0606] n is 0 or 1.

[0607] Preferably, the compound of formula X is selected from sub-formulas X-1 and X-2

[0608]

[0609] The radicals and parameters occurring therein have the meanings given above for formula X.

[0610] Particularly preferably, the medium according to the invention comprises one or more compounds selected from the group consisting of compounds of the formulae X-1-1 to X-1-9

[0611]

[0612] In a preferred embodiment, the medium according to the invention comprises one or more compounds of the formula XI

[0613]

[0614] in

[0615] R S represents H, alkyl or alkoxy having 1 to 12 C atoms, or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, in which one or more CH 2 - Groups can be substitution, and one or more H atoms may be replaced by F,

[0616] In each occurrence, they are expressed independently of each other

[0617]

[0618] Where R L , identically or differently on each occurrence, represents H, Cl or linear, branched or cyclic alkyl having 1 to 6 C atoms,

[0619] L S1 , L S2 Identically or differently, H, Cl or F,

[0620] R S1 , R S2 , identically or differently, denote H, alkyl or alkenyl having up to 6 C atoms, or cyclopropyl, cyclobutyl, cyclopentenyl or cyclopentyl,

[0621] R Th1 , R Th2 identically or differently, denotes H, alkyl or alkenyl or alkoxy having up to 6 C atoms, or cyclopropyl, cyclobutyl, cyclopentenyl or cyclopentyl,

[0622] Z S1 , Z S2 , Z S3 Identically or differently, represents -CH=CH-, -CH=CF-, -CF=CH-, -CF=CF-, -C≡C-, or a single bond,

[0623] a, b are identical or different and are 0 or 1.

[0624] Preferably, the compound of formula XI is selected from the compounds of formula XI-1 to XI-24:

[0625]

[0626]

[0627]

[0628]

[0629] The radicals occurring therein have the meanings given above for formula XI, and preferably

[0630] R S represents an alkyl or alkenyl group having 2 to 6 carbon atoms, wherein one or more CH 2 - Groups can be Alternative,

[0631] R S1 and R S2 Identically or differently, denotes H or an alkyl radical having 1 to 6 C atoms, preferably H,

[0632] R S3 represents H, F or alkyl with up to 6 C atoms, or cyclopropyl, preferably H, F or ethyl, very preferably H,

[0633] L S1 and L S2 Identically or differently, represents H or F, preferably F.

[0634] In a preferred embodiment, the medium comprises one or more compounds of formula XII

[0635]

[0636] in

[0637] R 12 represents H, alkyl or alkoxy having 1 to 12 C atoms or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, wherein one or more CH 2 - The group can be Replacement, or represents the group R P ,

[0638] R P Indicates halogen, CN, NCS, R F , R F -O- or R F -S-, where

[0639] R F represents a fluorinated alkyl or fluorinated alkenyl group having up to 9 C atoms,

[0640] Z 11 , Z 12 identically or differently represent -CH=CH-, -CF=CF-, -CH=CF-, -CF=CH-, -C≡C- or a single bond, preferably represent -C≡C- or a single bond,

[0641] X1 1 、X1 2 、X1 3 and X1 4 Identically or differently represent Cl or F, preferably represent F, t is 0 or 1, and and a) the group consisting of 1,4-phenylene, 1,4-naphthylene and 2,6-naphthylene, in which one or two CH groups may be replaced by N and in which one or more H atoms may be replaced by L, excluding tetrafluoro-1,4-phenylene,

[0642] b) the group consisting of: trans-1,4-cyclohexylene, 1,4-cyclohexenylene, bicyclo[1.1.1]pentane-1,3-diyl, 4,4′-bicyclohexylene, bicyclo[2.2.2]octane-1,4-diyl, spiro[3.3]heptane-2,6-diyl, wherein one or more non-adjacent CH 2 The group may be replaced by -O- and / or -S- and one or more H atoms may be replaced by F,

[0643] c) the group consisting of: thiophene-2,5-diyl, thieno[3,2-b]thiophene-2,5-diyl, selenophene-2,5-diyl, each of which may also be mono- or polysubstituted by L,

[0644] L, in each occurrence, represents F, Cl, CN, SCN, SF, either identically or differently 5 or straight-chain or branched, in each case optionally fluorinated, alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy having 1 to 12 C atoms.

[0645] The compound of formula XII is preferably selected from the group consisting of compounds of sub-formulae XII-1 to XII-11.

[0646]

[0647]

[0648] in

[0649] L 1 , L 2 and L 3 represents, identically or differently, H, F, Cl, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclopentenyl, and

[0650] R T , X 11 , X 12 , X 13 and X 14 has the meaning given above, R T Very preferably represents an alkyl radical having 1 to 7 C atoms, and X 11 , X 12 , X 13 and X 14 Indicates F.

[0651] In a preferred embodiment, the medium according to the invention comprises one or more compounds of the formula T

[0652]

[0653] in

[0654] R T Indicates halogen, CN, NCS, R F , R F -O- or R F -S-, where

[0655] R F represents a fluorinated alkyl or fluorinated alkenyl group having up to 12 C atoms,

[0656] and

[0657] At each occurrence, they are expressed independently of each other

[0658] L 4 and L 5 represents, identically or differently, F, Cl or a straight-chain, branched or cyclic alkyl or alkenyl group each having up to 12 C atoms;

[0659] Z T3 , Z T4 represent, identically or differently, -CH=CH-, -CF=CF-, -CH=CF-, -CF=CH-, -C≡C- or a single bond, and

[0660] t is either 0 or 1.

[0661] In a preferred embodiment, the liquid-crystalline media according to the invention comprise one or more compounds selected from the group of compounds of the following formulae T-1a to T-3b:

[0662]

[0663]

[0664] in

[0665] and has the meaning given to it above, and

[0666] n is 1, 2, 3, 4, 5, 6 or 7, preferably 1, 2, 3 or 4, particularly preferably 1.

[0667] In a particularly preferred embodiment of the invention, the medium comprises one or more compounds selected from the compounds of the formulae T-1a and T-2a.

[0668] Preferably, the compound of formula T-1a is selected from the group of compounds of the following sub-formulae:

[0669]

[0670]

[0671] wherein n is 1, 2, 3 or 4, preferably 1.

[0672] Preferably, the compound of formula T-2a is selected from the group of compounds of the following sub-formulae:

[0673]

[0674]

[0675] wherein n is 1, 2, 3 or 4, preferably 1.

[0676] Very preferably, the medium according to the invention comprises one or more compounds of the formula T-1a-5.

[0677] In one embodiment, the medium according to the invention comprises one or more compounds of the formula I, II, III, IV, V, VI, VII, VIII, IX, X, in which the radical R 1 , R 2 , R 3 , R 41 , R 42 , R 51 , R 52 , R 61 , R 62 , R 71 , R 72 , R 81 , R 82 , R 91 , R 92 , R 101 , R 102 and R S are cyclic alkyl groups respectively.

[0678] Very preferred compounds containing cyclic alkyl groups are selected from compounds of formula Cy-1 to Cy-14

[0679]

[0680]

[0681]

[0682] The medium according to the invention comprises one or more chiral dopants. Preferably, the absolute value of the helical twisting power (HTP) of these chiral dopants is between 1 μm -1 Up to 150μm -1 In the range of 10 μm, preferably -1 Up to 100 μm -1In the case where the medium contains two or more chiral dopants, these may have opposite signs of their HTP values. For some specific embodiments, this condition is preferred because it allows to compensate the chirality of the corresponding compounds to a certain extent and can therefore be used to compensate for various temperature-dependent properties of the resulting medium in the device. However, in general, it is preferred that most of the chiral compounds, preferably all of the chiral compounds present in the medium according to the invention have the same sign of their HTP values.

[0683] Preferably, the chiral dopants present in the medium according to the present application are mesogenic compounds and most preferably they themselves exhibit a mesogenic phase.

[0684] In a preferred embodiment of the invention, the medium comprises two or more chiral compounds which all have the same algebraic sign of HTP.

[0685] The temperature dependence of the HTP of the individual compounds may be high or low. The temperature dependence of the pitch of the medium may be compensated by mixing compounds with different temperature dependencies of the HTP in corresponding ratios.

[0686] For the optically active component, a variety of chiral dopants are available to the person skilled in the art, some of which are commercially available, for example cholesteryl nonanoate, R- and S-811, R- and S-1011, R- and S-2011, R- and S-3011, R- and S-4011 or CB15 (all from Merck KGaA, Darmstadt).

[0687] Particularly suitable dopants are compounds which contain one or more chiral groups and one or more mesogenic groups, or one or more aromatic or alicyclic groups which form mesogenic groups with chiral groups.

[0688] Suitable chiral groups are, for example, chiral branched hydrocarbon groups, chiral ethylene glycol, binaphthol or dioxolane, furthermore mono- or polyvalent chiral groups selected from the group consisting of sugar derivatives, sugar alcohols, sugar acids, lactic acid, chiral substituted diols, steroid derivatives, terpenoid derivatives, amino acids or sequences of several (preferably 1 to 5) amino acids.

[0689] Preferred chiral groups are sugar derivatives, such as glucose, mannose, galactose, fructose, arabinose and dextrose; sugar alcohols, such as sorbitol, mannitol, iditol, galactitol or their dehydrated derivatives, in particular dianhydrohexitols, such as dianhydrosorbitol (1,4:3,6-dianhydro-D-sorbitol, isosorbide), dianhydromannitol (isosorbide) or dianhydroiditol (isoiditol); sugar acids, such as gluconic acid, gulonic acid and ketogulonic acid; chiral substituted diol groups, such as mono- or oligoethylene glycol or propylene glycol, in which one or more CH 2 The group is substituted by an alkyl or alkoxy group; an amino acid, for example, alanine, valine, phenylglycine or phenylalanine or a sequence of 1 to 5 of these amino acids; a steroid derivative, for example, a cholesteryl or cholic acid group; a terpene derivative, for example, menthyl, neomenthyl, campheyl, pineyl, terpineyl, isolongifolyl, fenchyl, carreyl, myrthenyl, nopyl, geraniyl, linaloyl, neryl, citronellyl or dihydrocitronellyl.

[0690] The medium according to the invention preferably comprises a chiral dopant which is selected from the group of known chiral dopants. Suitable chiral groups and mesogenic chiral compounds are described, for example, in DE 34 25 503, DE 35 34 777, DE 35 34 778, DE 35 34779 and DE 35 34 780, DE 43 42 280, EP 01 038 941 and DE 195 41 820. Examples are also the compounds listed in Table F below.

[0691] The chiral compounds preferably used according to the present invention are selected from the formulae shown below.

[0692] Particularly preferred are chiral dopants selected from the compounds of the following formulae AI to A-III and A-Ch:

[0693]

[0694]

[0695] in

[0696] R a11 , R a12 and R b12 independently of one another represent an alkyl radical having 1 to 15 C atoms, wherein, in addition, one or more non-adjacent CH2 The groups may each be independently replaced by -C(R z )=C(R z )-, -C≡C-, -O-, -S-, -CO-, -CO-O-, -O-CO- or -O-CO-O-, with the O and / or S atoms not being directly attached to one another, and wherein, in addition, one or more H atoms may each be replaced by F, Cl, Br, I or CN, preferably alkyl, more preferably n-alkyl, with the proviso that R a12 With R b12 different

[0697] R a21 and R a22 independently of one another represent an alkyl radical having 1 to 15 C atoms, wherein, in addition, one or more non-adjacent CH 2 The groups may each be independently replaced by -C(R z )=C(R z )-, -C≡C-, -O-, -S-, -CO-, -CO-O-, -O-CO- or -O-CO-O-, in such a way that the O and / or S atoms are not directly connected to one another, and wherein, in addition, one or more H atoms may be replaced by F, Cl, Br, I or CN, preferably both of which are alkyl, more preferably n-alkyl,

[0698] R a31 , R a32 and R b32 independently of one another represent straight-chain and branched alkyl radicals having 1 to 15 C atoms, wherein, in addition, one or more non-adjacent CH 2 The groups may each be independently replaced by -C(R z )=C(R z )-, -C≡C-, -O-, -S-, -CO-, -CO-O-, -O-CO- or -O-CO-O- are replaced in such a way that the O and / or S atoms are not directly connected to one another, and wherein, in addition, one or more H atoms may be replaced by F, Cl, Br, I or CN,

[0699] Preferably it is alkyl, more preferably n-alkyl, provided that R a32 With R b32 different,

[0700] R z Indicates H, CH 3 , F, Cl or CN, preferably H or F,

[0701] R 8 With the R given above a11 one of the meanings of , preferably alkyl, more preferably n-alkyl having 1 to 15 C atoms,

[0702] Z 8 Indicates -C(O)O-, CH 2 O, CF 2 O or a single bond, preferably -C(O)O-,

[0703] A 11 As shown below A 12 defined, or alternatively

[0704]

[0705] A 12 express

[0706]

[0707] Preferably

[0708]

[0709] in

[0710] L 12 represents, independently of one another, halogen, CN or alkyl, alkenyl, alkoxy or alkenyloxy having up to 12 C atoms and in which one or more H atoms are optionally replaced by halogen, preferably methyl, ethyl, Cl or F, particularly preferably F,

[0711] A 21 express

[0712]

[0713] A 22 With A 12 The meaning given

[0714] A 31 With A 11 The meaning given,

[0715] or alternatively

[0716]

[0717] A 32 With A 12 The meaning given.

[0718] n2 is 0, 1, or 2, identically or differently, at each occurrence, and

[0719] n3 is 1, 2, or 3, and

[0720] r is 0, 1, 2, 3 or 4.

[0721] Particularly preferred are dopants selected from the group consisting of compounds of the following formula:

[0722]

[0723]

[0724] in

[0725] m is an integer from 1 to 9, the same or different at each occurrence, and

[0726] n is an integer from 2 to 9, identically or differently at each occurrence.

[0727] Particularly preferred compounds of formula A are compounds of formula A-III.

[0728] Further preferred dopants are derivatives of isosorbide, isomannide or isoidide of the following formula A-IV:

[0729]

[0730] Among them for

[0731] (Dianhydrosorbitol),

[0732] (dianhydromannitol), or

[0733] (Iditol dianhydrogenate),

[0734] Preferably it is dianhydrosorbitol,

[0735] and chiral glycols, for example, diphenyl glycol (hydrogenated benzoin), in particular mesogenic hydrogenated benzoin derivatives of the following formula AV:

[0736]

[0737] including the (S,S) enantiomer not shown,

[0738] in

[0739] are each independently 1,4-phenylene (which may also be mono-, di- or trisubstituted by L) or 1,4-cyclohexylene,

[0740] L is H, F, Cl, CN or an optionally halogenated alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl or alkoxycarbonyloxy group having 1 to 7 carbon atoms,

[0741] c is 0 or 1,

[0742] X is CH 2 or -C(O)-,

[0743] Z 0 It is -COO-, -OCO-, -CH 2 CH 2 - or a single key, and

[0744] R 0 It is an alkyl group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group or an alkylcarbonyloxy group having 1 to 12 carbon atoms.

[0745] Examples of compounds of formula IV are:

[0746]

[0747]

[0748] Compounds of formula A-IV are described in WO 98 / 00428. Compounds of formula AV are described in GB-A-2,328,207.

[0749] Very particularly preferred dopants are chiral binaphthyl derivatives as described in WO 02 / 94805, chiral binaphthol acetal derivatives as described in WO 02 / 34739, chiral TADDOL derivatives as described in WO 02 / 06265 and chiral dopants having at least one fluorinated bridging group and a terminal or central chiral group as described in WO 02 / 06196 and WO 02 / 06195.

[0750] Particularly preferred are chiral compounds of formula A-VI

[0751]

[0752] in

[0753] X 1 , X 2 , Y 1 and Y 2 Each is independently F, Cl, Br, I, CN, SCN, SF 5 , straight-chain or branched alkyl with 1 to 25 C atoms, which is unsubstituted or mono- or polysubstituted by F, Cl, Br, I or CN and in which, in addition, one or more non-adjacent CH 2 The groups can be independently replaced by -O-, -S-, -NH-, NR x-, -CO-, -COO-, -OCO-, -OCOO-, -S-CO-, -CO-S-, -CH=CH- or -C≡C- in such a way that the O and / or S atoms are not directly bonded to one another, polymerizable radicals with up to 20 C atoms or cycloalkyl or aryl radicals, which may optionally be mono- or polysubstituted by halogen, preferably F, or by polymerizable radicals,

[0754] x 1 and x 2 are each independently 0, 1 or 2,

[0755] y 1 and 2 are each independently 0, 1, 2, 3 or 4,

[0756] B 1 and B 2 Each independently of one another is an aromatic or partially or fully saturated aliphatic six-membered ring, in which one or more CH groups may each be replaced by an N atom and one or more non-adjacent CH 2 The groups can be replaced by O or S individually,

[0757] W 1 and W 2 Each independently of the other is -Z 1 -A 1 -(Z 2 -A 2 ) m -R, and either alternatively R 1 or A 3 , but they are not both H, or

[0758] yes

[0759] or

[0760]

[0761] U 1 and U 2 Each independently is CH 2 , O, S, CO or CS,

[0762] V 1 and V 2 Each independently of each other is (CH 2 ) n , where one to four non-adjacent CH 2 The groups may be replaced by O or S, and V 1 and V 2 one of them

[0763] yes In the case of both are single bonds,

[0764] n is 1, 2, or 3

[0765] Z 1 and Z 2 Each is independently -O-, -S-, -CO-, -COO-, -OCO-, -O-COO-, -CO-NR x -,-NR x -CO-, -O-CH 2 -,-CH 2 -O-, -S-CH 2 -,-CH 2 -S-, -CF 2 -O-, -O-CF 2 -, -CF 2 -S-, -S-CF 2 -,-CH 2 -CH 2 -, -CF 2 -CH 2 -,-CH 2 -CF 2 -, -CF 2 -CF 2 -, -CH=N-, -N=CH-, -N=N-, -CH=CH-, -CF=CH-, -CH=CF-, -CF=CF-, -C≡C-, a combination of two of these radicals, wherein no two O and / or S and / or N atoms are directly bonded to one another, preferably -CH=CH-COO- or -COO-CH=CH- or a single bond,

[0766] R x represents an alkyl group having 1 to 6 C atoms,

[0767] A 1 , A 2 and A 3 are each independently 1,4-phenylene, in which one or two non-adjacent CH groups may each be replaced by N, 1,4-cyclohexylene, in which one or two non-adjacent CH 2 The radicals may each be replaced by O or S, 1,3-dioxolane-4,5-diyl, 1,4-cyclohexenylene, 1,4-bicyclo[2.2.2]octylene, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl or 1,2,3,4-tetrahydronaphthalene-2,6-diyl, wherein each of these radicals may be mono- or polysubstituted by L, and in addition A 1 Can be a single key,

[0768] L is a halogen atom, preferably F, CN, NO 2 , alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl or alkoxycarbonyloxy having 1 to 7 C atoms, wherein one or more H atoms may each be replaced by F or Cl,

[0769] m is independently at each occurrence 0, 1, 2 or 3, and

[0770] R and R 1 Each independently is H, F, Cl, Br, I, CN, SCN, SF 5 , straight-chain or branched alkyl radicals having 1 or 3 to 25 C atoms, which may optionally be mono- or polysubstituted by F, Cl, Br, I or CN and one or more non-adjacent CH 2 The groups can be each replaced by -O-, -S-, -NH-, -NR 0 -, -CO-, -COO-, -OCO-, -O-COO-, -S-CO-, -CO-S-, -CH=CH- or -C≡C-, wherein no two O and / or S atoms are directly bonded to each other, or a polymerizable group.

[0771] Particularly preferred are chiral binaphthyl derivatives of formula A-VI-1

[0772]

[0773] Among them, ring B, R 0 and Z 0 As defined for Formulas A-IV and AV, and b is 0, 1 or 2.

[0774] In particular those selected from the following formulae A-VI-1a to A-VI-1c:

[0775]

[0776] Among them, ring B, R 0 , and Z 0 As defined for Formula A-VI-1, and

[0777] R 0 As defined in formula A-IV, or H or an alkyl group having 1 to 4 carbon atoms, and b is 0, 1 or 2,

[0778] and Z 0 In particular -OC(O)- or a single bond.

[0779] The concentration of the one or more chiral dopants in the LC medium is preferably 0.001% to 20%, preferably 0.05% to 5%, more preferably 0.1% to 2%, and most preferably 0.5% to 1.5%. These preferred concentration ranges apply in particular to the chiral dopants S-4011 or R-4011 (both from Merck KGaA) and chiral dopants with the same or similar HTP. For chiral dopants with higher or lower absolute HTP values ​​compared to S-4011, these preferred concentrations must be proportionally reduced, or proportionally increased, according to their HTP value relative to S-4011.

[0780] The pitch p of the LC medium or host mixture according to the invention is preferably in the range from 5 to 50 μm, more preferably in the range from 8 to 30 μm and particularly preferably in the range from 10 to 20 μm.

[0781] Preferably, the medium according to the invention comprises a stabilizer chosen from compounds of formulae ST-1 to ST-18.

[0782]

[0783]

[0784]

[0785]

[0786] in

[0787] R ST represents H, alkyl or alkoxy radicals having 1 to 15 C atoms, wherein in addition one or more of these radicals CH 2 The groups can be independently replaced by -C≡C-, -CF 2 O-, -OCF 2 -, -CH=CH-, -O-, -CO-O-, -O-CO- are substituted in such a way that the O atoms are not directly connected to one another, and wherein, in addition, one or more H atoms may be substituted by halogen,

[0788] express

[0789]

[0790]

[0791] Z ST Each independently represents -CO-O-, -O-CO-, -CF 2 O-, -OCF 2 -,-CH2 O-, -OCH 2 -,-CH 2 -,-CH 2 CH 2 -,-(CH 2 ) 4 -, -CH=CH-CH 2 O-, -C 2 F 4 -,-CH 2 CF 2 -, -CF 2 CH 2 -, -CF=CF-, -CH=CF-, -CF=CH-, -CH=CH-, -C≡C- or a single bond,

[0792] L 1 and L 2 Each independently represents F, Cl, CF 3 or CHF 2 ,

[0793] p means 1 or 2,

[0794] q represents 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10.

[0795] Among the compounds of formula ST, the compounds of formula

[0796]

[0797] Where n = 1, 2, 3, 4, 5, 6 or 7, preferably n

[0798] =1 or 7

[0799]

[0800] Where n = 1, 2, 3, 4, 5, 6 or 7, preferably n

[0801] =3

[0802]

[0803] Where n = 1, 2, 3, 4, 5, 6 or 7, preferably n

[0804] =3

[0805]

[0806]

[0807] In the compounds of formulae ST-3a and ST-3b, n preferably represents 3. In the compounds of formula ST-2a, n preferably represents 7.

[0808] Very particularly preferred mixtures according to the invention comprise one or more stabilizers selected from the group consisting of compounds of the formulae ST-2a-1, ST-3a-1, ST-3b-1, ST-8-1, ST-9-1 and ST-12:

[0809]

[0810]

[0811] The compounds of the formulae ST-1 to ST-18 are preferably each present in the liquid-crystal mixture according to the invention in an amount of 0.005 to 0.5%, based on the mixture.

[0812] If the mixtures according to the invention comprise two or more compounds of the formulae ST-1 to ST-18, the concentration is increased accordingly in the case of two compounds to 0.01 to 1%, based on the mixture.

[0813] However, the total proportion of compounds of the formulae ST-1 to ST-18, based on the mixture according to the invention, should not exceed 2%.

[0814] The compounds according to the present invention can be synthesized by or similar to known methods described in the literature (e.g. in standard works, such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart) under reaction conditions known and suitable for the reaction. Variants known per se can also be used here, but are not mentioned here again. In particular, they can be prepared as described in the following reaction scheme or similar to the following reaction scheme. Other methods for preparing the compounds of the present invention can be obtained from the examples.

[0815] Other mesogenic compounds not explicitly mentioned above can optionally and advantageously also be used in the media according to the invention. Such compounds are known to those skilled in the art.

[0816] In a preferred embodiment of the present invention, the total concentration of the compounds of the formula U in the liquid-crystalline medium is 1% or more, preferably 4% or more, more preferably 7% or more and especially preferably 9% or more.

[0817] In a preferred embodiment of the present invention, the liquid-crystalline media preferably comprise in total 2% to 30%, preferably 5% to 25% and particularly preferably 10% to 20% of compounds of the formula U.

[0818] In a preferred embodiment of the present invention, the liquid-crystalline medium comprises a total of 10% to 45%, preferably 15% to 40% and particularly preferably 20% to 35% of a compound of the formula T, the compound of the formula T being preferably selected from the formulae T-1a, T-2a and T-3a, very preferably selected from T-1a-5 and T-2a-4.

[0819] In a preferred embodiment of the present invention, the liquid-crystalline medium comprises in total 15% to 35%, preferably 18% to 32% and particularly preferably 20% to 30% of compounds of the formula T-1a.

[0820] In a preferred embodiment, the medium comprises one or more compounds of the formula I, preferably compounds of the formula I-2 or formula I-3, in a total concentration ranging from 2% to 50%, more preferably from 5% to 30% and especially preferably from 10% to 25%.

[0821] In a preferred embodiment, the medium comprises one or more compounds of formula I-2, preferably compounds of formula I-2c and / or formula I-2d, in a total concentration ranging from 1% to 30%, more preferably from 5% to 25% and especially preferably from 10% to 20%.

[0822] In a preferred embodiment, the medium comprises one or more compounds of the formula I-3, preferably compounds of the formula I-3b and / or formula I-3d, in a total concentration ranging from 1% to 35%, more preferably from 10% to 30% and especially preferably from 15% to 25%.

[0823] In a preferred embodiment of the invention, the medium comprises one or more compounds of the formula II, preferably compounds of the formula II-1, in a total concentration of 5% to 30%, more preferably 10% to 25%, particularly preferably 12% to 20%.

[0824] In a preferred embodiment of the invention, the medium comprises one or more compounds of the formula IIA-1 in a total concentration of 5% to 25%, more preferably 8% to 20%, particularly preferably 10% to 15%.

[0825] In a preferred embodiment of the present invention, the medium comprises one or more compounds of the formula II-1 in a total concentration of 30% or less, more preferably 25% or less, particularly preferably 20% or less.

[0826] In a preferred embodiment of the present invention, the medium contains one or more compounds of formula III, preferably compounds of formula III-1 and / or III-2, more preferably compounds III-1i and / or III-1b, in a total concentration of 15% to 70%, more preferably 25% to 60%, and particularly preferably 35% to 50%.

[0827] Further preferred embodiments of the present invention are as follows, alone or in combination with one another, wherein some of the compounds are abbreviated using the acronyms given in Table C below:

[0828] - the medium comprises one, two, three, four or more compounds of the formula III-1, preferably selected from the compounds of the formula III-1b, III-1f and III-1i; more preferably III-1b and III-1i;

[0829] - the medium preferably contains the compound of formula III-1b in a total concentration ranging from 2% to 30%, more preferably from 5% to 25%, in particular from 10% to 20%;

[0830] - the medium contains the compound of formula III-1b at a total concentration of 10% or more;

[0831] - the medium preferably contains the compound of formula III-1i in a total concentration ranging from 10% to 40%, more preferably from 15% to 38%, in particular from 20% to 35%,

[0832] - the medium contains the compounds PPU-TO-S and / or PPTU-TO-S and / or PTPU-TO-S and / or PP(1)-TO-S;

[0833] - the medium preferably comprises one or more compounds of the formula U and one or more compounds of the formula T in a total concentration ranging from 25% to 55%, in particular from 30% to 50%;

[0834] - the medium contains one or more compounds of formula I-2d, preferably PGU-2-S and / or PGU-3-S and / or PGU-4-S;

[0835] - the medium comprises one or more compounds of formula I-2d and II-1b, preferably PGU-3-S and / or PGU-4-S and PTU-3-S and / or PTU-4-S and / or PTU-5-S;

[0836] - the medium contains one or more compounds of the formula PPTU-nS and / or PTPU-nS, the total concentration of which is in the range of 10 to 20%;

[0837] - the medium contains one or more compounds of the formula PPTU-nS and / or PTPU-nS and / or PGTU-nS, in a total concentration ranging from 15 to 30%, wherein n is 2, 3, 4, 5 or 6;

[0838] - the medium comprises compounds of the formula CPTU-nS and PPTU-nS, wherein n is 2, 3, 4, 5 or 6;

[0839] - the medium comprises a compound of formula XII-3, preferably formula CPU(F,F)-nS, wherein n is 2, 3, 4 or 5;

[0840] The medium comprises one or more compounds of the formula ST-3, preferably ST-3a and / or ST-3b, particularly preferably ST-3b-1, in a total concentration in the range from 0.01 to 1%, preferably from 0.05 to 0.5%, in particular from 0.10 to 0.15%.

[0841] The liquid-crystalline media according to the invention preferably have a clearing point of 90° C. or higher, more preferably 100° C. or higher, more preferably 110° C. or higher, more preferably 120° C. or higher, more preferably 130° C. or higher, particularly preferably 140° C. or higher and very particularly preferably 150° C. or higher.

[0842] The liquid-crystalline media according to the invention preferably have a clearing point of 160° C. or less, more preferably 140° C. or less, particularly preferably 120° C. or less and very particularly preferably 100° C. or less.

[0843] The nematic phase of the medium according to the invention preferably extends at least from 0° C. or lower to 90° C. or higher. Advantageously, the medium according to the invention exhibits an even broader nematic phase range, preferably at least from -10° C. or lower to 120° C. or higher, very preferably at least from -20° C. or lower to 140° C. or higher, and in particular, at least from -30° C. or lower to 150° C. or higher, very particularly preferably at least from -40° C. or lower to 170° C. or higher.

[0844] At 1 kHz and 20° C., the Δ∈ of the liquid-crystal media according to the invention is preferably 1 or more, more preferably 2 or more and very preferably 3 or more.

[0845] At 589nm (Na D ) and 20° C., the birefringence (Δn) of the liquid-crystalline medium according to the invention is preferably 0.280 or more, more preferably 0.300 or more, even more preferably 0.320 or more, very preferably 0.330 or more and in particular 0.350 or more.

[0846] At 589nm (Na D ) and 20° C., the Δn of the liquid-crystal media according to the invention is preferably in the range from 0.200 to 0.900, more preferably in the range from 0.250 to 0.800, even more preferably in the range from 0.300 to 0.700 and very particularly preferably in the range from 0.350 to 0.600.

[0847] In a preferred embodiment of the present application, the Δn of the liquid-crystal medium according to the invention is preferably 0.50 or more, more preferably 0.55 or more.

[0848] The compounds of the formulae I to III include in each case dielectrically positive compounds having a dielectric anisotropy greater than 3, dielectrically neutral compounds having a dielectric anisotropy less than 3 and greater than −1.5 and dielectrically negative compounds having a dielectric anisotropy of −1.5 or less.

[0849] The compounds of the formulae I, II and III are preferably dielectrically positive.

[0850] In the present application, the expression dielectric positivity describes compounds or components where Δε>3.0, dielectric neutrality describes those where -1.5≤Δε≤3.0, and dielectric negativity describes those where Δε<-1.5. Δε is measured at a frequency of 1 kHz and at 20°C. The dielectric anisotropy of each compound is determined by the results of a 10% solution of each individual compound in a nematic host mixture. If the solubility of each compound in the host mixture is less than 10%, the concentration is reduced to 5%. The capacitance of the test mixture is measured in both a box with a homeotropic orientation and a box with a planar orientation. The box thickness of both types of boxes is about 20 μm. The applied voltage is a rectangular wave with a frequency of 1 kHz and an effective value of typically 0.5 V to 1.0 V, but it is always selected to be lower than the capacitance threshold of each test mixture.

[0851] Δε is defined as (ε||-ε ⊥ ), and ε ave . is (ε||+2ε ⊥ ) / 3.

[0852] The host compound used for the determination of the physical constants of the pure compounds by extrapolation was ZLI-4792 from Merck KGaA, Germany. The absolute values ​​of the dielectric constant, birefringence (Δn) and rotational viscosity (γ 1 ) is measured from the change in the respective value of the bulk mixture after addition of the compound. The concentration in the bulk is 10%, or 5% in case of insufficient solubility. The value is extrapolated to 100% concentration of the added compound.

[0853] In the examples, the phase sequence of pure compounds is given using the following abbreviations:

[0854] Tg: glass transition, K: crystalline, N: nematic, SmA: smectic A, SmB: smectic B, I: isotropic.

[0855] The component having a nematic phase was measured as it was at a measuring temperature of 20° C., and all other components were treated like compounds.

[0856] In both cases, unless explicitly stated otherwise, the expression "threshold voltage" in this application refers to the optical threshold and is for a 10% relative contrast ratio (V 10) and the expression "saturation voltage" refers to optical saturation and is for 90% relative contrast (V 90 ). Capacitive threshold voltage (V 0 ), also known as the Freedericks threshold (V Fr ).

[0857] Unless expressly stated otherwise, the parameter ranges indicated in this application include the limit values.

[0858] The different upper and lower value limits indicated for the different property ranges combine with one another to give further preferred ranges.

[0859] Throughout the application, the following conditions and definitions apply, unless otherwise stated. All concentrations are given in weight percent and relate to the respective overall mixture, all temperature values ​​are given in degrees Celsius and all temperature differences are given in differential degrees. All physical properties are determined according to "Merck Liquid Crystals, Physical Properties of Liquid Crystals", Status November 1997, Merck KGaA (Germany) and are given for a temperature of 20°C, unless explicitly stated otherwise. The optical anisotropy (Δn) is determined at a wavelength of 589.3 nm. The dielectric anisotropy (Δε) is determined at a frequency of 1 kHz. The threshold voltage and all other electro-optical properties are determined using a test cell produced by Merck KGaA, Germany. The cell thickness of the test cell used to determine Δε is approximately 20 μm. The electrodes are 1.13 cm 2 The circular ITO electrode with a 200 mm area and a guard ring. For the homeotropic orientation (ε||), the alignment layer is SE-1211 from Nissan Chemicals, Japan, and for the planar orientation (ε||), the alignment layer is SE-1211 from Nissan Chemicals, Japan. ⊥ ), the orientation layer is polyimide AL-1054 from Japan SyntheticRubber. Using a Solatron 1260 frequency response analyzer, a sine wave and 0.3V rms The capacitance is determined by the voltage at which the capacitance is measured. The light used in the electro-optical measurement is white light. An apparatus using a commercially available DMS instrument from Autronic-Melchers, Germany, is used here. The characteristic voltage is determined under perpendicular observation. The threshold voltage (V 10 )、Mid-gray voltage (V 50 ) and saturation voltage (V 90 ).

[0860] As in A.Penirschke et al. "Cavity Perturbation Method for Characterization of Liquid Crystals up to 35GHz", 34 th The liquid crystal media described in the European Microwave Conference—Amsterdam, pp. 545-548, were investigated in the microwave frequency range with regard to their properties. In this respect, A. Gaebler et al., “Direct Simulation of Material Permittivities…”, 12 MTC 2009—International Instrumentation and Measurement Technology Conference, Singapore, 2009 (IEEE), pp. 463-467 and DE 10 2004 029 429 A, in which the measurement methods are likewise described in detail, are also compared.

[0861] Liquid crystals are introduced into polytetrafluoroethylene (PTFE) or quartz capillaries. The inner diameter of the capillary is 0.5 mm and the outer diameter is 0.78 mm. The effective length is 2.0 cm. The filled capillary is introduced into the center of a cylindrical cavity with a resonant frequency of 19 GHz. The length of the cavity is 11.5 mm and the radius is 6 mm. An input signal (source) is then applied and the frequency-dependent response of the cavity is recorded using a commercial vector network analyzer (N5227APNA microwave network analyzer, Keysight Technologies Inc. USA). For other frequencies, the dimensions of the cavity are adapted accordingly.

[0862] The change in resonance frequency and Q factor between the measurement using a capillary filled with liquid crystal and the measurement using a capillary not filled with liquid crystal is used to determine the dielectric constant and loss angle at the corresponding target frequency, which is obtained by the above-mentioned publication A. Penirschke et al., 34 th Equations 10 and 11 are determined as described in European Microwave Conference—Amsterdam, pp. 545-548.

[0863] The values ​​of the components of the properties perpendicular and parallel to the director of the liquid crystal are obtained by the alignment of the liquid crystal in a magnetic field. For this purpose, the magnetic field of a permanent magnet is used. The magnetic field strength is 0.35 Tesla.

[0864] Preferred components are phase shifters, varactor diodes, wireless and radio wave antenna arrays, matching circuits, adaptive filters and others.

[0865] In this application, the term "compound" means one compound as well as a plurality of compounds, unless specifically stated otherwise.

[0866] All mixtures according to the present invention are nematic. The liquid crystal medium according to the present invention preferably has a nematic phase within the preferred range given above. Here, the statement that there is a nematic phase means that on the one hand, no smectic phase is observed at low temperatures at the corresponding temperature and no crystallization is observed, and on the other hand, no clearing occurs when heating from the nematic phase. At high temperatures, the clearing point is measured in a capillary by conventional methods. The study at low temperature is carried out in a flow viscometer at the corresponding temperature and is checked by the storage of bulk samples: at a given temperature T, the storage stability (LTS) in the bulk of the medium according to the present invention is determined by visual inspection. 2g of the medium of interest is filled into a closed glass container (bottle) of a suitable size placed in a refrigerator at a predetermined temperature. Check the bottle at a defined time interval whether a smectic phase or crystallization occurs. For each material and each temperature, two bottles are stored. If the appearance of crystallization or smectic phase is observed in at least one of the two corresponding bottles, the test is terminated, and the time of the last inspection before the appearance of a higher ordered phase is observed is recorded as the corresponding storage stability. Finally the test was terminated after 1000 hours, ie an LTS value of 1000 hours means that the mixture was stable at a given temperature for at least 1000 hours.

[0867] The liquid crystals used preferably have a positive dielectric anisotropy, which is preferably 2 or more, preferably 4 or more, particularly preferably 6 or more and very particularly preferably 10 or more.

[0868] Furthermore, the liquid crystal media according to the invention are characterized by high anisotropy values ​​in the microwave range. The birefringence at about 19 GHz is, for example, preferably 0.14 or more, particularly preferably 0.15 or more, particularly preferably 0.20 or more, particularly preferably 0.25 or more and very particularly preferably 0.30 or more. In addition, the birefringence is preferably 0.80 or less.

[0869] In the above and below:

[0870] V o Indicates the threshold voltage at 20°C, capacitance [V]

[0871] n e It represents the extraordinary refractive index at 20°C and 589nm.

[0872] n o It represents the ordinary refractive index at 20℃ and 589nm.

[0873] Δn represents the optical anisotropy at 20°C and 589 nm.

[0874] ε ⊥ represents the dielectric permittivity perpendicular to the director at 20°C and 1kHz,

[0875] ε || represents the dielectric permittivity parallel to the director at 20°C and 1kHz,

[0876] Δε represents the dielectric anisotropy at 20°C and 1kHz,

[0877] cl.p.,T(N,I) represents the clearing point [℃],

[0878] γ 1 Indicates the rotational viscosity measured at 20°C

[0879] K 1 Indicates the elastic constant and "bending" deformation at 20°C [pN],

[0880] K 2 Indicates the elastic constant and "twist" deformation at 20°C [pN],

[0881] K 3 Indicates the elastic constant and "bending" deformation at 20°C [pN],

[0882] K avg. It means that at 20℃ it is defined as The average elastic constant [pN], and

[0883] LTS stands for Low Temperature Stability (Nematic Phase) determined as detailed in test cells or in bulk.

[0884] The dielectric anisotropy in the microwave range is defined as

[0885] Δε r ≡(ε r,|| -ε r,⊥ ).

[0886] The tunability (τ) is defined as

[0887] τ≡(Δε r / ε r,|| ).

[0888] Material quality (η) is defined as

[0889] η≡(τ / tanδ εr,max. ),in

[0890] The maximum dielectric loss is

[0891] tanδε r,max≡max.{tanδε r,⊥ ,;tanδε r,||}.

[0892] The tunability τ of the medium according to the invention measured at 20° C. and 19 GHz is 0.250 or more, preferably 0.300 or more, 0.310 or more, 0.320 or more, 0.330 or more, or 0.340 or more, very preferably 0.345 or more and in particular 0.350 or more.

[0893] Preferably, the material quality (η) of the liquid crystal material is 6 or more, preferably 8 or more, preferably 10 or more, preferably 15 or more, preferably 17 or more, preferably 20 or more, particularly preferably 25 or more and very particularly preferably 30 or more.

[0894] In the corresponding components, the phase shifter quality of the preferred liquid crystal material is 15° / dB or greater, preferably 20° / dB or greater, preferably 30° / dB or greater, preferably 40° / dB or greater, preferably 50° / dB or greater, particularly preferably 80° / dB or greater and very particularly preferably 100° / dB or greater.

[0895] However, in some embodiments, liquid crystals having negative values ​​of dielectric anisotropy may also be advantageously used.

[0896] The liquid crystals used are either a single substance or a mixture and preferably have a nematic phase.

[0897] The liquid crystal medium according to the invention may contain other additives and chiral dopants in the usual concentrations. The total concentration of these other components is 0% to 10%, preferably 0.1% to 6%, based on the entire mixture. The concentration of the individual compounds used is preferably 0.1% to 3% each. When the values ​​and concentration ranges of the liquid crystal components and liquid crystal compounds of the liquid crystal medium are quoted in this application, the concentrations of these and similar additives are not taken into account.

[0898] Preferably, the media according to the invention contain one or more chiral compounds as chiral dopants to adjust their cholesteric pitch. Their total concentration in the media according to the invention is preferably in the range of 0.05% to 15%, more preferably 1% to 10% and most preferably 2% to 6%.

[0899] Optionally, the media according to the invention may contain other liquid crystal compounds to adjust the physical properties. Such compounds are known to the expert. Their concentration in the media according to the invention is preferably 0% to 30%, more preferably 0.1% to 20% and most preferably 1% to 15%.

[0900] Respectively, for relative tuning or relative contrast ratio of photoelectric response varying from 0% to 90% (t90 –t 0 ) time, the response time is based on the rise time (τ on ) is given, that is, including the delay time (t 10 –t 0 ); for relative tuning or relative contrast ratio of photoelectric response changing from 100% back to 10% (t 100 –t 10 ) time, the response time is the decay time (τ off ) is given, and the total response time (τ 总计 =τ on +τ off ).

[0901] The liquid crystal medium according to the present invention consists of a plurality of compounds, preferably 3 to 30, more preferably 4 to 20 and very preferably 4 to 16 compounds. These compounds are mixed in a conventional manner. Usually, the desired amount of compound used in a smaller amount is dissolved in the compound used in a larger amount. If the temperature is above the clearing point of the compound used in a higher concentration, it is particularly easy to observe that the dissolution process is complete. However, the medium can also be prepared in other conventional ways, for example using a so-called premix, which can, for example, be a homogeneous mixture or a eutectic mixture of compounds, or using a so-called "multi-bottle" system, the components of which are themselves ready-to-use mixtures.

[0902] All temperatures, such as melting points T(C, N) or T(C, S), the transition from the smectic (S) phase to the nematic (N) phase T(S, N) and the clearing point of the liquid crystal T(N, I), are expressed in degrees Celsius. All temperature differences are expressed as a difference in degrees.

[0903] In the present invention and in particular in the following examples, the structures of the mesogenic compounds are indicated by abbreviations (also called acronyms). In these acronyms, the chemical formulae are simplified using the following Tables A to D. All groups C n H 2n+1 , C m H 2m+1 and C l H 2l+1 or C n H 2n-1 , C m H 2m-1 and C l H 2l-1 =Respectively represent straight-chain alkyl or alkenyl groups with n, m or 1 C atoms in each case, preferably 1-E-alkenyl. Table A lists the codes used for the ring elements of the core structure of the compounds, while Table B lists the connecting groups. Table C gives the meaning of the codes for the left-hand or right-hand end groups. Table D shows exemplary structures of compounds and their respective abbreviations.

[0904] Table A: Ring elements

[0905]

[0906]

[0907]

[0908]

[0909]

[0910] Table B: Linking Groups

[0911]

[0912] Table B: End Groups

[0913]

[0914]

[0915] Use in combination with other

[0916]

[0917] where n and m each represent an integer, and the three dots "..." are placeholders for other abbreviations from this table.

[0918] The following table shows exemplary structures and their respective abbreviations. These are shown to illustrate the meaning of the abbreviation rules. They also represent compounds that are preferably used.

[0919] Table C: Exemplary Structure

[0920] The following exemplary structures are compounds which are preferably additionally used in the medium:

[0921]

[0922]

[0923]

[0924]

[0925]

[0926]

[0927]

[0928]

[0929]

[0930]

[0931]

[0932]

[0933]

[0934] wherein m and n are the same or different and are 1, 2, 3, 4, 5, 6 or 7.

[0935] Preferably, the medium according to the invention comprises one or more compounds chosen from the compounds of Table C.

[0936] The following table, Table D, shows exemplary compounds that can be used as alternative stabilizers in the mesogenic medium according to the invention. The total concentration of these and similar compounds in the medium is preferably 5% or less.

[0937] Table D

[0938]

[0939]

[0940] In a preferred embodiment of the present invention, the mesogenic medium comprises one or more compounds selected from the compounds from Table D.

[0941] The following table, Table E, shows exemplary compounds which can preferably be used as chiral dopants in the mesogenic medium according to the present invention.

[0942] Table E

[0943]

[0944]

[0945]

[0946] In a preferred embodiment of the present invention, the mesogenic medium comprises one or more compounds selected from the compounds from Table E.

[0947] The mesogenic medium according to the present application preferably comprises two or more, preferably four or more compounds selected from the compounds from the above table. Example

[0948] The following examples illustrate the invention without limiting it in any way.

[0949] It is clear to the person skilled in the art what properties can be achieved from the physical properties and to what extent they can be modified. In particular, the combinations of various properties which can preferably be achieved are therefore well defined to the person skilled in the art.

[0950] Synthesis Example

[0951] Abbreviation: RT Room temperature (usually 20℃±1℃)

[0952] THF Tetrahydrofuran

[0953] MTB ether methyl tert-butyl ether

[0954] DCM Dichloromethane

[0955] dist. Distillation

[0956] Example 1: 2-butyl-5-[2-[4-(3,5-difluoro-4-isothiocyanato-phenyl)phenyl]ethynyl]-1,3-difluoro-benzene

[0957] Step 1.1: 2-(4-Butyl-3,5-difluoro-phenyl)ethynyl-trimethyl-silane

[0958] 5-Bromo-2-butyl-1,3-difluoro-benzene (CAS-no. 160976-00-1, 15.1 g, 61 mmol), trimethylsilyl acetylene (17.6 ml, 124 mmol), diisopropylamine (70 ml), copper (I) iodide (277 mg, 1.5 mmol) and bis (triphenylphosphine) -palladium (II) chloride (1.7 g, 2.4 mmol) were heated at reflux temperature overnight. The reaction mixture was then cooled to RT, and MTB ether and distilled water were added. The aqueous phase was separated and extracted with MTB ether. The combined organic phases were washed with brine, dried (sodium sulfate) and concentrated in vacuo. The residue was purified by silica gel chromatography (n-heptane) to give 2- (4-butyl-3,5-difluoro-phenyl) ethynyl -trimethyl-silane as a yellow oil.

[0959] Step 1.2: 2-Butyl-5-ethynyl-1,3-difluoro-benzene

[0960]

[0961] Tetra-n-butylammonium fluoride (1M in THF, 60 ml) is added dropwise to a solution of 2-(4-butyl-3,5-difluoro-phenyl)ethynyl-trimethyl-silane (15.9 g, 60 mmol) in THF (350 ml) at RT, and the reaction mixture is stirred overnight. It is then hydrolyzed by adding HCl (1 N) and distilled water, and MBT ether is added. The aqueous phase is separated and extracted with MTB ether. The combined organic phases are washed with brine, dried (sodium sulfate) and concentrated in vacuo. The residue is purified by silica gel chromatography (heptane) to give 2-butyl-5-ethynyl-1,3-difluoro-benzene as a pale yellow oil.

[0962] Step 1.3: 4-[4-[2-(4-Butyl-3,5-difluoro-phenyl)ethynyl]phenyl]-2,6-difluoro-aniline

[0963]

[0964] A solution of 2-butyl-5-ethynyl-1,3-difluoro-benzene (4.6 g, 24 mmol), 4-(4-bromophenyl)-2,6-difluoro-aniline (CAS-no. 2244281-20-5, 7.0 g, 23 mmol) and diisopropylamine (55 ml) in THF (60 ml) was heated at reflux temperature. Copper (I) iodide (4.4 mg), 2-biscyclohexylphosphino-2'4'6'-triisopropyl-1,1'-biphenyl (22 mg) and chloro(2-biscyclohexylphosphino-2'4'6'-triisopropyl-1,1'-biphenyl)(2'-amino-1,1'-biphenyl-2-yl)palladium (II) (37 mg) were added and the reaction mixture was stirred at reflux temperature overnight. It was then cooled to RT, filtered and concentrated in vacuo. The residue was purified by chromatography on silica gel (heptane / MTB ether 5 / 1) and crystallization (heptane) to give 4-[4-[2-(4-butyl-3,5-difluoro-phenyl)ethynyl]phenyl]-2,6-difluoro-aniline as brown crystals.

[0965] Step 1.4: 2-Butyl-5-[2-[4-(3,5-difluoro-4-isothiocyanato-phenyl)phenyl]ethynyl]-1,3-difluoro-benzene

[0966]

[0967] A solution of 4-[4-[2-(4-butyl-3,5-difluoro-phenyl)ethynyl]phenyl]-2,6-difluoro-aniline (7.4 g, 19 mmol) and 1,4-diazabicyclo[2.2.2]octane (5.2 g, 47 mmol) in DCM (70 ml) was cooled to 0 ° C and treated dropwise with thiophosgene (1.6 ml, 20 mmol). The reaction mixture was stirred at RT for 60 minutes. Subsequently, it was hydrolyzed with brine, and the aqueous phase was separated and extracted with DCM. The combined organic phases were washed with brine, dried (sodium sulfate) and concentrated in vacuo. The residue was purified by silica gel chromatography (heptane) and crystallization (heptane) to give 2-butyl-5-[2-[4-(3,5-difluoro-4-isothiocyanato-phenyl)phenyl]ethynyl]-1,3-difluoro-benzene as light orange crystals.

[0968] Phase sequence: K 84 N 174 IK 84 N 174.0 I

[0969] Δε=7.40

[0970] Δn=0.4180

[0971] γ 1 =735mPas

[0972] Similar to Synthesis Example 1, the following compound was obtained:

[0973]

[0974]

[0975]

[0976]

[0977]

[0978] Mixture Examples

[0979] Liquid crystal mixtures N1 to N19 and comparative mixture C1 were prepared having the compositions and properties indicated in the following table and characterized according to their general physical properties at 19 GHz and 20° C. and their suitability for use in microwave devices.

[0980] Comparative mixture C1

[0981]

[0982]

[0983] Example N1

[0984]

[0985]

[0986] Example N1 corresponds to comparative mixture C1 and additionally comprises the inventive compound of the formula U. An improvement in the material quality η from 34.5 to 39.7 was observed.

[0987] Example N2

[0988]

[0989] Example N3

[0990]

[0991]

[0992] Example N4

[0993]

[0994] Embodiment N5

[0995]

[0996]

[0997] Example N6

[0998]

[0999] Embodiment N7

[1000]

[1001]

[1002] Embodiment N8

[1003]

[1004] Embodiment N9

[1005]

[1006]

[1007] Embodiment N10

[1008]

[1009] Example N11

[1010]

[1011]

[1012] Example N12

[1013]

[1014] Example N13

[1015]

[1016]

[1017] Example N14

[1018]

[1019] Embodiment N15

[1020]

[1021] Example N16

[1022]

[1023] Example N17

[1024]

[1025] Example N18

[1026]

[1027]

[1028] Example N19

[1029]

[1030] Example N20

[1031]

[1032]

[1033] Example N21

[1034]

[1035] Example N22

[1036]

[1037]

[1038] Example N23

[1039]

[1040] Example N24

[1041]

[1042] Example N25

[1043]

[1044]

[1045] Example N26

[1046]

[1047] Example N27

[1048]

[1049] Example N28

[1050]

[1051]

[1052] Example N29

[1053]

Claims

1. A compound selected from the group consisting of compounds of formula U-2, U-11 and U-12 in L 1 represents H, F, Cl, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl or cyclopentenyl, and R U represents H, alkyl or alkoxy having 1 to 12 C atoms or alkenyl, alkenyloxy or alkoxyalkyl having 2 to 12 C atoms, wherein one or more CH2- groups may be replaced by Replacement, or represents the group R P , R P Indicates halogen, CN, NCS, R F , R F -O- or R F -S-, where R F represents a fluorinated alkyl or fluorinated alkenyl group having up to 9 C atoms, X 1 and X 2 represent, identically or differently, H, Cl, F, CH3 or C2H5, Y 1 and Y 2 independently represents H or F, Y 3 and Y 4 Indicates H.

2. A compound according to claim 1, wherein the group X 1 and X 2 Indicates H or F.

3. A compound according to claim 1 or 2, wherein R U represents an alkyl group having 1 to 12 C atoms.

4. A compound according to claim 1 or 2, wherein the group R U represents R as defined in claim 1 P .

5. A liquid-crystalline medium comprising one or more compounds according to any one of claims 1 to 4.

6. A liquid-crystalline medium according to claim 5, wherein the medium comprises one or more compounds selected from the group of compounds of the formulae I, II and III in R 1 represents H, unfluorinated alkyl or unfluorinated alkoxy having 1 to 17 C atoms or unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl having 2 to 15 C atoms, wherein one or more CH2- groups may be replaced by Instead, n is 0, 1, or 2, to In each occurrence, they are expressed independently of each other Where R L In each occurrence, the same or different representation of H or Alkyl with 1 to 6 C atoms, and wherein Alternatively, R 2 represents H, unfluorinated alkyl or unfluorinated alkoxy having 1 to 17 C atoms or unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl having 2 to 15 C atoms, wherein one or more CH2- groups may be replaced by Instead, Z 21 represents trans-CH=CH-, trans-CF=CF- or -C≡C-, and and Independently express Where R L In each occurrence, the same or different representation of H or Alkyl having 1 to 6 C atoms; R 3 represents H, unfluorinated alkyl or unfluorinated alkoxy having 1 to 17 C atoms or unfluorinated alkenyl, unfluorinated alkenyloxy or unfluorinated alkoxyalkyl having 2 to 15 C atoms, wherein one or more CH2- groups may be replaced by Instead, Z 31 and Z 32 One of them represents trans-CH=CH-, trans-CF=CF- or -C≡C-, and the other of them independently represents -C≡C-, trans-CH=CH-, trans-CF=CF- or a single bond, and to Independently express Where R L In each occurrence, the same or different representation of H or Alkyl having 1 to 6 C atoms, and wherein Alternatively, and Alternatively, 7. A liquid-crystalline medium according to claim 5 or 6, wherein the medium comprises one or more compounds selected from the group of compounds of the formulae I-1 to I-5 in L 1 , L 2 and L 3 In each occurrence, it represents H or F, either identically or differently, and R 1 , and has the meaning given for formula I in claim 6.

8. A liquid-crystalline medium according to claim 5 or 6, wherein the medium comprises one or more compounds selected from the group of compounds of the formulae II-1 to II-3 in R 2 , and has the meaning given in claim 6 for formula II.

9. A liquid-crystalline medium according to claim 5 or 6, wherein the medium comprises one or more compounds selected from the group of compounds of the formulae III-1 to III-6 in R 3 , and has the meaning given for formula III in claim 6, and Z 31 and Z 32 represents trans-CH=CH- or trans-CF=CF- independently of each other, and in Formula III-6, Z 31 and Z 32 One of them may alternatively represent -C≡C-.

10. A liquid-crystalline medium according to claim 5 or 6, wherein the medium comprises one or more compounds of the formula T in R T Indicates halogen, CN, NCS, R F , R F -O- or R F -S-, where R F represents a fluorinated alkyl or fluorinated alkenyl group having up to 12 C atoms, and In each occurrence, they are expressed independently of each other L 4 and L 5 represents, identically or differently, F, Cl or a straight-chain, branched or cyclic alkyl or alkenyl group each having up to 12 C atoms; Z T3 , Z T4 represent, identically or differently, -CH=CH-, -CF=CF-, -CH=CF-, -CF=CH-, -C≡C- or a single bond, and t is 0 or 1.

11. A component for high frequency technology, characterized in that It comprises a liquid-crystalline medium according to any one of claims 5 to 10.

12. The component of claim 11, wherein the component is a liquid crystal based antenna element, a phase shifter, a tunable filter, a tunable metamaterial structure, a matching network or a varactor diode.

13. A microwave antenna array, characterized in that It comprises one or more components according to claim 11 or 12.

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