DE102005045848A1 - New chromane and chromene derivatives useful as components in liquid crystalline media and in liquid crystal display element or electrooptical display element - Google Patents

Abstract

Chromane derivatives (A) and chromene derivatives (A1) are new. Chromane derivatives (A) of formulae (I and II) and chromene derivatives (A1) of formulae (III-VI) are new. R 1>a linear or branched 1-15C alkyl, 2-15C alkenyl (both optionally chiral, unsubstituted, substituted with CN, CF 3 or halo, where one or more CH 2-groups are replaced through -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=CH-, -CH=CF-, -CF=CH-, -CF=CF-, -C?=C- or -cyclicbutane-), H or halo (F, Cl, Br or I); R 2>alkyl- or alkoxy with 1-15C atoms, alkenyl- or alkenyloxy with 2-15C atoms (all optionally substituted with F), H, F, Cl, NCS, CN or SF 5; A 1>, A 2>trans-1,4-cyclohexylene (where one or more non-adjacent CH 2-groups are replaced by -O- and/or -S-), 1,4-phenylene (where one or two CH-groups are replaced by N and one or more H atoms by F), 1,4-bicyclo(2,2,2)-octylene, piperidin-1,4-diyl, naphthalin-2,6-diyl, decahydronaphthalin-2,6-diyl, 1,2,3,4-tetrahydronaphthalin-2,6-diyl or 1,4-cyclohexenylene; Z 1>, Z 2>-O-, -CH 2O-, -OCH 2-, -CO-O-, -O-CO-, -CF 2O-, -OCF 2-, -CF 2CF 2-, -CH 2CF 2-, -CF 2CH 2-, -CH 2CF 2O-, -OCF 2CH 2-, -CH 2CH 2-, -CH=CH-, -CH=CF-, -CF=CH-, -CF=CF-, -CF=CF-CO-O-, -O-CO-CF=CF-, -C?=C- or a bond; L 1>-L 4>alkyl- or alkoxy with 1-15C, alkenyl- or alkenyloxy with 2-15C atoms (all optionally substituted with one or more F), H, F, Cl, NCS, CN, SF 5 (preferably H or F); m : 0-4 (preferably 0-2); and n : 1-4 (preferably 1-2). Provided that the sum of m and n is 1-4 (preferably 1-2). In formula (II): L 2>L 3>oxy-compounds of formula (a-f); and L 5>, L 6>H, F, Cl, CN or -(Z 2>-A 2>-) nR 2>. Provided that when L 5> and L 6> is H, F, Cl or CN, then m is 1-4 (preferably 1-2); and when L 5> and L 6> is -(Z 2>-A 2>-) nR 2>, then m and n is 0-4 and the sum of m and n is 1-4 (preferably 1-3). Independent claims are also included for: (1) liquid crystalline medium comprising at least two liquid crystalline components of (I-VI); (2) liquid crystal display element comprising liquid crystalline medium; and (3) electrooptical display element comprising liquid crystalline medium as dielectric. [Image] [Image] [Image] [Image].

Description

The The present invention relates to chroman derivatives, processes for their use Production and its use as component (s) in liquid-crystalline Media. About that In addition, the present invention relates to liquid crystal and electro-optical Display elements containing the liquid-crystalline media according to the invention.

The according to the invention, liquid-crystalline Connections can as component (s) of liquid-crystalline Media are used, especially for displays based on the principle the twisted cell, the guest-host effect, the effect of deformation more upright Phases DAP or ECB (Electrically Controlled Birefringence), the IPS effect (in plane switching) or the effect of the dynamic Scattering based.

benzofused Oxygen heterocycles are suitable components for liquid crystalline Mixtures which are in liquid crystal and electro-optical display elements can be used.

als Komponenten flüssigkristalliner Mischungen in der JP 06/256337 offenbart, wobei R¹, R², X, Y, Z, m und n die in diesem Dokument angegebenen Bedeutungen aufweisen.Thus, dihydrobenzofuran and chroman derivatives become the following formula

disclosed as components of liquid crystalline mixtures in JP 06/256337, wherein R ¹ , R ² , X, Y, Z, m and n have the meanings given in this document.

als Komponenten flüssigkristalliner Mischungen werden in der JP 06/256339 offenbart, wobei R¹, R² und X die in diesem Dokument angegebenen Bedeutungen aufweisen.Chroman derivatives of the following formula

as components of liquid-crystalline mixtures are disclosed in JP 06/256339, wherein R ¹ , R ² and X have the meanings given in this document.

In In addition, the above-mentioned documents also provide methods for Preparation of benzofuran and chroman derivatives disclosed.

Of the Invention was based on the object new stable, liquid crystalline or mesogenic compounds which, as component (s), are liquid-crystalline Media, especially for TN, STN, IPS, TFT and VA displays.

Furthermore It was an object of the present invention, liquid-crystalline compounds to provide, which have a high dielectric anisotropy Δε, depending on the substitution either positive or negative. Furthermore should the compounds of the invention be thermally, chemically and photochemically stable. Furthermore, should the compounds of the invention one possible have broad nematic phase and excellent with nematic Base mixtures, especially at low temperatures, miscible be.

Surprisingly, it has been found that the chroman derivatives according to the invention are particularly suitable as component (s) of liquid-crystalline media. With their help, it is possible to obtain stable, liquid-crystalline media, in particular suitable for TFT or STN displays. The compounds of the invention are both thermal and UV stable. Also, they are characterized by high dielectric anisotropies Δε, due to which lower threshold voltages are required in the application. In addition, the compounds according to the invention have a broad nematic phase range as well as a high voltage holding ratio. Also advantageous is the good solubility of the compounds according to the invention, on account of which they are particularly suitable for increasing the low-temperature stability of polar liquid-crystal mixtures.

By suitable choice of the ring members and / or the terminal substituents can be the physical properties of the liquid crystals of the invention vary widely.

There the chroman unit in its length between the usual six-membered 1- and 2-Kerner, the derivatives of the invention are characterized In addition, by positive elastic properties.

liquid crystalline Media with very small values of optical anisotropy are in particular for reflective and transflective applications of importance, i. such applications, where the respective LCD no or only supportive backlight experiences.

With the provision of chroman derivatives of the invention is quite in general, the range of liquid crystalline Substances that differ in different, application-related Aspects are suitable for the preparation of liquid-crystalline mixtures, considerably widened.

The Chroman derivatives according to the invention have a wide range of applications. Depending on the selection of the Substituents can these compounds serve as base materials from which liquid crystalline Media for the most part Part are composed. It can but also the compounds of the invention liquid crystalline Base materials from other classes of compounds are added, for example, the dielectric and / or optical anisotropy to influence such a dielectric and / or its threshold voltage and / or its viscosity to optimize.

The Chroman derivatives according to the invention are colorless in the pure state and form liquid-crystalline mesophases in a for the electro-optical application favorable located temperature range. Chemical, thermal and against light they are stable.

worin
R¹ H, Halogen (F, Cl, Br, I), einen linearen oder verzweigten, gegebenenfalls chiralen, unsubstituierten, einen einfach durch CN oder CF₃ oder einen mindestens einfach durch Halogen substituierten Alkylrest mit 1 bis 15 C-Atomen oder Alkenylrest mit 2 bis 15 C-Atomen, worin auch eine oder mehrere CH₂-Gruppen jeweils unabhängig voneinander durch -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=CH-, -CH=CF-, -CF=CH-, -CF=CF-, -C≡C- oder

so ersetzt sein können, dass Heteroatome nicht direkt miteinander verknüpft sind,
R² H, F, Cl, NCS, CN, SF₅, einen Alkyl- oder Alkoxyrest mit 1 bis 15 C-Atomen, einen Alkenyl- oder Alkenyloxyrest mit 2 bis 15 C-Atomen, einen durch ein oder mehrere Fluoratome substituierten Alkyl- oder Alkoxyrest mit 1 bis 15 C-Atomen oder einen durch ein oder mehrere Fluoratome substituierten Alkenyl- oder Alkenyloxyrest mit 2 bis 15 C-Atomen,
A¹, A² jeweils unabhängig voneinander, gleich oder verschieden

• a) trans-1,4-Cyclohexylen, worin auch eine oder mehrere nicht benachbarte CH₂-Gruppen durch -O- und/oder -S- ersetzt sein können,
• b) 1,4-Phenylen, worin eine oder zwei CH-Gruppen durch N ersetzt sein können und worin auch ein oder mehrere H-Atome durch F ersetzt sein können,
• c) einen Rest aus der Gruppe 1,4-Bicyclo(2,2,2)-octylen, Piperidin-1,4-diyl, Naphthalin-2,6-diyl, Decahydronaphthalin-2,6-diyl und 1,2,3,4-Tetrahydronaphthalin-2,6-diyl, oder
• d) 1,4-Cyclohexenylen,

Z¹, Z² jeweils unabhängig voneinander, gleich oder verschieden -O-, -CH₂O-, -OCH₂-, -CO-O-, -O-CO-, -CF₂O-, -OCF₂-, -CF₂CF₂-, -CH₂CF₂-, -CF₂CH₂-, -CH₂CF₂O-, -OCF₂CH₂-, -CH₂CH₂-, -CH=CH-, -CH=CF-, -CF=CH-, -CF=CF-, -CF=CF-CO-O-, -O-CO-CF=CF-, -C≡C- oder eine Einfachbindung,
L¹, L², L³ jeweils unabhängig voneinander, gleich oder verschieden H, F, Cl, NCS, CN, SF₅, einen durch ein oder mehrere Fluoratome substituierten Alkyl- oder Alkoxyrest mit 1 bis 15 C-Atomen oder einen durch ein oder mehrere Fluoratome substituierten Alkenyl- oder Alkenyloxyrest mit 2 bis 15 C-Atomen, vorzugsweise H, F, Cl oder CN, und besonders bevorzugt H oder F,
m 0, 1, 2, 3 oder 4, vorzugsweise 0, 1, 2 oder 3 und besonders bevorzugt 0, 1 oder 2, bedeutet, und
n 1, 2, 3 oder 4, vorzugsweise 1, 2 oder 3 und besonders bevorzugt 1 oder 2, bedeutet,
jedoch mit der Maßgabe, dass die Summe (m + n) = 1, 2, 3 oder 4, vorzugsweise 1, 2 oder 3 und besonders bevorzugt 1 oder 2, ist,
und der allgemeinen Formel (II)

worin R¹, A¹ und Z¹ die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen,
L¹, L², L³ und L⁴ jeweils unabhängig voneinander, gleich oder verschieden H, F, Cl, NCS, CN, SF₅, einen durch ein oder mehrere Fluoratome substituierten Alkyl- oder Alkoxyrest mit 1 bis 15 C-Atomen oder einen durch ein oder mehrere Fluoratome substituierten Alkenyl- oder Alkenyloxyrest mit 2 bis 15 C-Atomen, vorzugsweise H, F, Cl oder CN, und besonders bevorzugt H oder F, bedeuten, wobei
einer der beiden Reste L² und L³ zusätzlich auch die Bedeutung von R² in bezug auf Formel (I) annehmen kann und
L² und L³ zusammen auch

L⁵ und L⁶ jeweils unabhängig voneinander, gleich oder verschieden H, F, Cl oder CN sowie einer der beiden Reste zusätzlich auch -(Z²-A²-)_nR², bedeuten,
jedoch mit der Maßgabe, dass wenn L⁵ und L⁶ jeweils unabhängig voneinander, gleich oder verschieden H, F, Cl oder CN bedeuten, m = 1, 2, 3 oder 4, vorzugsweise 1, 2 oder 3 und besonders bevorzugt 1 oder 2, ist und dass wenn einer der beiden Reste -(Z²-A²-)_nR² bedeutet, m und n jeweils unabhängig voneinander, gleich oder verschieden 0, 1, 2, 3 oder 4 sind, wobei die Summe (m + n) = 1, 2, 3 oder 4, vorzugsweise 1, 2 oder 3, ist,
sowie Chromen-Derivate der allgemeinen Formeln (III) und (IV)

worin R¹, R², A¹, A², Z¹, Z², L¹, L², L³, m und n die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen,
und Chromen-Derivate der allgemeinen Formeln (V) und (VI)

worin R¹, A¹, Z¹, L¹, L², L³, L⁴ und m die in bezug auf Formel (II) angegebenen Bedeutungen aufweisen.The present invention thus provides chroman derivatives of the general formula (I)

wherein
R ¹ H, halogen (F, Cl, Br, I), a linear or branched, optionally chiral, unsubstituted, a simply by CN or CF ₃ or at least one halogen-substituted alkyl radical having 1 to 15 carbon atoms or alkenyl radical 2 to 15 C atoms, wherein also one or more CH ₂ groups are each independently of one another by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O -, -CH = CH-, -CH = CF-, -CF = CH-, -CF = CF-, -C≡C- or

may be replaced so that heteroatoms are not directly linked,
R ^{2 is} H, F, Cl, NCS, CN, SF ₅ , an alkyl or alkoxy radical having 1 to 15 C atoms, an alkenyl or alkenyloxy radical having 2 to 15 C atoms, an alkyl radical which is substituted by one or more fluorine atoms or alkoxy radical having 1 to 15 C atoms or an alkenyl or alkenyloxy radical having 2 to 15 C atoms substituted by one or more fluorine atoms,
A ¹ , A ^{2 are} each independently, the same or different

• a) trans-1,4-cyclohexylene, in which also one or more non-adjacent CH ₂ groups can be replaced by -O- and / or -S-,
• b) 1,4-phenylene, wherein one or two CH groups may be replaced by N and wherein also one or several H atoms can be replaced by F,
• c) a radical from the group consisting of 1,4-bicyclo (2,2,2) octyl, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2, 3,4-tetrahydronaphthalene-2,6-diyl, or
• d) 1,4-cyclohexenylene,

Each of Z ¹ , Z ² is independently, identically or differently -O-, -CH ₂ O-, -OCH ₂ -, -CO-O-, -O-CO-, -CF ₂ O-, -OCF ₂ -, -CF ₂ CF ₂ -, -CH ₂ CF ₂ -, -CF ₂ CH ₂ -, -CH ₂ CF ₂ O-, -OCF ₂ CH ₂ -, -CH ₂ CH ₂ -, -CH = CH-, - CH = CF-, -CF = CH-, -CF = CF-, -CF = CF-CO-O-, -O-CO-CF = CF-, -C≡C- or a single bond,
L ¹ , L ² , L ³ each independently, identically or differently H, F, Cl, NCS, CN, SF ₅ , a substituted by one or more fluorine atoms alkyl or alkoxy radical having 1 to 15 carbon atoms or one by a or a plurality of fluorine atoms substituted alkenyl or alkenyloxy having 2 to 15 carbon atoms, preferably H, F, Cl or CN, and particularly preferably H or F,
m is 0, 1, 2, 3 or 4, preferably 0, 1, 2 or 3 and particularly preferably 0, 1 or 2, and
n is 1, 2, 3 or 4, preferably 1, 2 or 3 and more preferably 1 or 2,
but with the proviso that the sum (m + n) = 1, 2, 3 or 4, preferably 1, 2 or 3 and more preferably 1 or 2,
and the general formula (II)

wherein R ¹ , A ¹ and Z ^{1 have} the meanings given in relation to formula (I),
L ¹ , L ² , L ³ and L ^{4 are} each independently, identically or differently H, F, Cl, NCS, CN, SF ₅ , a substituted by one or more fluorine atoms alkyl or alkoxy radical having 1 to 15 carbon atoms or a substituted by one or more fluorine atoms alkenyl or Alkenyloxyrest having 2 to 15 carbon atoms, preferably H, F, Cl or CN, and particularly preferably H or F, wherein
one of the two radicals L ² and L ³ additionally can also assume the meaning of R ² with respect to formula (I) and
L ² and L ³ together too

L ⁵ and L ⁶ each independently, identically or differently H, F, Cl or CN and one of the two radicals additionally also - (Z ² -A ² -) _n R ² , mean
but with the proviso that when L ⁵ and L ^{6 are} each independently, identically or differently H, F, Cl or CN, m = 1, 2, 3 or 4, preferably 1, 2 or 3 and most preferably 1 or 2 is, and that when one of the two radicals - (Z ² -A ² -) _n R ² , m and n are each independently, identically or differently 0, 1, 2, 3 or 4, wherein the sum (m + n) = 1, 2, 3 or 4, preferably 1, 2 or 3,
and chromene derivatives of the general formulas (III) and (IV)

in which R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² , L ³ , m and n have the meanings given in relation to formula (I),
and chromene derivatives of the general formulas (V) and (VI)

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² , L ³ , L ⁴ and m have the meanings given in relation to formula (II).

Prefers are the chroman derivatives of the general formulas (I) and (II).

One Another object of the present invention is the use of chroman derivatives of the formulas (I) and (II) and chromene derivatives of the formulas (III) to (VI) as component (s) in liquid-crystalline media.

Also The present invention relates to liquid-crystalline media with at least two liquid-crystalline ones Components containing at least one chroman and / or chromene derivative of the formulas (I) to (VI).

object The present invention also relates to liquid crystal display elements, in particular electro-optical display elements, which serve as a dielectric an inventive, liquid crystalline Medium included.

In a preferred embodiment have the compounds of the invention of the formula (I) to (VI) has a negative Δε. Due to the negative Δε these are suitable Compounds especially for a use in VA displays.

The present invention thus also relates in particular to VA TFT displays with dielectrics which contain at least one chroman and / or chromene derivative of the formulas (I) to (VI) with negative Δε contain.

In a further preferred embodiment have the compounds of the invention of the formula (I) to (VI) on a positive Δε. Due to the positive Δε these are suitable Compounds especially for a use in highly polar mixtures.

The present invention thus also relates in particular to TFT displays with a low threshold voltage (so-called "low-V _th -TFT displays") and IPS displays (so-called "in plane switching displays"), with dielectrics having at least one chroman - And / or chromene derivative of the formulas (I) to (VI) with positive Δε included.

Provided the compounds of the invention of the formulas (I) to (VI) additionally have a low birefringence Δn in addition to a positive Δε, These compounds are particularly suitable for use in reflective and transflective liquid crystal display elements as well as other liquid crystal displays with low birefringence Δn, so-called "low Δn mode displays", such as reflective and transflective TN displays.

object The present invention thus also includes reflective ones and transflective TN displays, with dielectrics containing at least a chroman and / or chromene derivative of the formulas (I) to (VI) with contain positive Δε.

Furthermore find the chroman and chromene derivatives of the formulas (I) to (VI) with positive Δε use as polar clarifiers in displays, which are operated at a temperature at which the control media in the isotropic phase or in an optically isotropic phase. Such displays are e.g. in DE-A-102 17 273, DE-A-102nd 53 325, DE-A-102 53 606 and DE-A-103 13 979 described.

The Meaning of the formulas (I) to (VI) includes all isotopes of the Compounds of formulas (I) to (VI) bonded chemical elements one. In enantiomerically pure or enriched form, the compounds are suitable of the formulas (I) to (VI) as chiral dopants and in general to achieve chiral mesophases.

Above and below, R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² , L ³ , L ⁴ , L ⁵ , L ⁶ , m and n have the meanings indicated, if not expressly stated otherwise. If the radicals A ¹ and Z ¹ and also A ² and Z ^{2 occur more} than once, they may independently of one another take on the same or different meanings.

For the sake of simplicity, Cyc denotes a 1,4-cyclohexylene radical, Che denotes a 1,4-cyclohexenylene radical, Dio denotes a 1,3-dioxane-2,5-diyl radical, Thp denotes a tetrahydropyran-2,5-diyl radical, Dit denotes a 1, 3-dithiane-2,5-diyl, Phe a 1,4-phenylene, Pyd a pyridine-2,5-diyl, Pyr a pyrimidine-2,5-diyl, Bco a bicyclo- (2,2,2) - octylene radical and Dec a Decahydronaphthalinrest, wherein Cyc and / or Phe can be unsubstituted or mono- or polysubstituted by -CH ₃ , -Cl, -F and / or -CN.

Preference is given to compounds of the formulas (I) to (VI) in which R ^{1 is} H, a linear alkyl or alkoxy radical having 1 to 10 C atoms or a linear alkenyl or alkenyloxy radical having 2 to 10 C atoms.

If R ^{1 is} halogen, it preferably means F or Cl, more preferably F.

Preference is given to compounds of the formulas (I) to (VI) in which R ^{2 is} F, Cl, CN, SF ₅ , CF ₃ , OCF ₃ or OCHF ₂ , particularly preferably F, CN, CF ₃ or OCF ₃ and in particular F ,

A ¹ and A ^{2 are} preferably Phe, Cyc, Che, Pyd, Pyr or Dio, and particularly preferably Phe or Cyc. Further preferred compounds of the formulas (I) to (VI) which contain no more than one of the radicals Dio, Dit, Pyd, Pyr or Bco.

Phe is preferable

Phe is particularly preferred

The terms 1,3-dioxane-2,5-diyl and Dio each include the two positional isomers

Z¹ und Z² bedeuten vorzugsweise -CH₂CH₂-, -CH=CH-, -C≡C-, -CF₂CF₂-, -CF=CF-, -COO-, -OCO-, -CF₂O-, -OCF₂- oder eine Einfachbindung, besonders bevorzugt -CF₂O-, -COO- oder eine Einfachbindung.The cyclohexene-1,4-diyl group preferably has the following structures:

Z ¹ and Z ^{2 are} preferably -CH ₂ CH ₂ -, -CH = CH-, -C≡C-, -CF ₂ CF ₂ -, -CF = CF-, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or a single bond, more preferably -CF ₂ O-, -COO- or a single bond.

L ¹ , L ² , L ³ , L ⁴ , L ⁵ and L ^{6 are} preferably H or F.

worin R¹, R², A¹, A², Z¹, Z², L¹, L², L³, m und n die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen.Preferred chroman derivatives of the general formula (I) are the following formulas (Ia) to (Id):

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² , L ³ , m and n have the meanings given in relation to formula (I).

Especially preferred are the chroman derivatives of the general formulas (Ia) and (Ib).

worin R¹, R², A¹, A², Z¹, Z², L¹, L² und L³ die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen.Preferred chroman derivatives of the general formula (Ia) are the following formulas (Ia1) to (Ia6):

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (I).

Especially preferred are the chroman derivatives of the general formulas (Ia1) to (Ia5), that is Chroman derivatives of the general formula (Ia) in which m = 0 or 1 is.

Also preferred are chroman derivatives of the general formulas (Ia1) to (Ia6) in which L ³ = H and L ¹ and L ² independently of one another, identically or differently, denote H or F, where it is especially preferred is when L ¹ = L ² = F, L ¹ = H and L ² = F or L ¹ = L ² = H.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹, L², L³ und L⁴ unabhängig voneinander, gleich oder verschieden H oder F bedeuten.A particularly preferred compound of sub-formula (Ia1) is that of sub-formula (Ia1a):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ , L ² , L ³ and L ⁴ independently of one another, identically or differently, denote H or F.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹, L², L³, L⁴, L⁵ und L⁶ unabhängig voneinander, gleich oder verschieden H oder F bedeuten.Particularly preferred compounds of sub-formula (Ia2) are those of sub-formula (Ia2a) to (Ia2c):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ , L ² , L ³ , L ⁴ , L ⁵ and L ⁶ independently, identically or differently mean H or F.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹, L², L³, L⁴, L⁵, L⁶, L⁷ und L⁸ unabhängig voneinander, gleich oder verschieden H oder F bedeuten.A particularly preferred compound of sub-formula (Ia3) is that of sub-formula (Ia3a):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ , L ² , L ³ , L ⁴ , L ⁵ , L ⁶ , L ⁷ and L ⁸ independently, identically or differently H or F. mean.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹, L², L³ und L⁴ unabhängig voneinander, gleich oder verschieden H oder F bedeuten.Particularly preferred compounds of sub-formula (Ia4) are those of sub-formulas (Ia4a) to (Ia4c):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ , L ² , L ³ and L ⁴ independently of one another, identically or differently, denote H or F.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹, L², L³, L⁴, L⁵ und L⁶ unabhängig voneinander, gleich oder verschieden H oder F bedeuten.Particularly preferred compounds of the sub-formula (Ia5) are those of the sub-formulas (Ia5a) to (Ia5i), in particular those of the sub-formulas (Ia5a) to (Ia5c),

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ , L ² , L ³ , L ⁴ , L ⁵ and L ⁶ independently, identically or differently mean H or F.

worin R¹, R², A¹, A², Z¹, Z², L¹, L² und L³ die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen.Preferred chroman derivatives of the general formula (Ib) are the following formulas (Ib1) to (Ib6):

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (I).

Particularly preferred are the chroman derivatives of the general formulas (Ib1), (Ib2) and (Ib4), ie chroman derivatives of the general formula (Ib) in which m = 0 or 1 and the sum (m + n ) 1 or 2.

Further preferred are chroman derivatives of the general formulas (Ib1) to (Ib6) in which L ³ = H and L ¹ and L ^{2 are} independently, identically or differently H or F, it being particularly preferred if at least one of Radicals L ¹ and L ² F means. In particular, L ¹ = L ² = F.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹ und L² unabhängig voneinander, gleich oder verschieden H oder F bedeuten, wobei besonders bevorzugt mindestens einer der Reste L¹ und L² F bedeutet, insbesondere aber beide der Reste.Particularly preferred compounds of sub-formula (Ib1) are those of sub-formulas (Ib1a) to (Ib1c):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ and L ^{2 are} independently, identically or differently H or F, particularly preferably at least one of L ¹ and L ^{2 is} F, in particular but both of the leftovers.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹ und L² unabhängig voneinander, gleich oder verschieden H oder F bedeuten, wobei besonders bevorzugt mindestens einer der Reste L¹ und L² F bedeutet, insbesondere aber beide der Reste.Particularly preferred compounds of sub-formula (Ib2) are those of sub-formulas (Ib2a) to (Ib2c):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ and L ^{2 are} independently, identically or differently H or F, particularly preferably at least one of L ¹ and L ^{2 is} F, in particular but both of the leftovers.

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹ und L² unabhängig voneinander, gleich oder verschieden H oder F bedeuten, wobei besonders bevorzugt mindestens einer der Reste L¹ und L² F bedeutet, insbesondere aber beide der Reste.Particularly preferred compounds of sub-formula (Ib4) are those of sub-formulas (Ib4a) and (Ib4b):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ and L ^{2 are} independently, identically or differently H or F, particularly preferably at least one of L ¹ and L ^{2 is} F, in particular but both of the leftovers.

worin R¹, A¹, Z¹, L¹, L², L³, L⁴ und m die in bezug auf Formel (II) und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen.Preferred chroman derivatives of the general formula (II) are the following formulas (IIa) to (IId):

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² , L ³ , L ⁴ and m have the meanings given in relation to formula (II) and R ² with respect to formula (I).

Especially preferred are the chroman derivatives of the general formulas (IIa) and (IIb).

worin R¹, A¹, Z¹, L¹, L² und L³ die in bezug auf Formel (II) und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen.Preferred chroman derivatives of the general formula (IIa) are the following formulas (IIa1) to (IIa3):

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (II) and R ² with respect to formula (I).

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹ und L² unabhängig voneinander, gleich oder verschieden H oder F bedeuten.Particularly preferred compounds of sub-formula (IIa1) are those of sub-formula (IIa1a) and (IIa1b):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ and L ² independently of one another, identically or differently, denote H or F.

worin R¹, A¹, Z¹, L¹, L² und L³ die in bezug auf Formel (II) und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen.Preferred chroman derivatives of the general formula (IIb) are the following formulas (IIb1) to (IIb3):

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (II) and R ² with respect to formula (I).

worin R¹ und R² die in bezug auf Formel (I) angegebenen Bedeutungen aufweisen und L¹ und L² unabhängig voneinander, gleich oder verschieden H oder F bedeuten, wobei besonders bevorzugt mindestens einer der Reste L¹ und L² F bedeutet, insbesondere aber beide der Reste.Particularly preferred compounds of sub-formula (IIb1) are those of sub-formulas (IIb1a) and (IIb1b):

wherein R ¹ and R ^{2 have} the meanings given in relation to formula (I) and L ¹ and L ^{2 are} independently, identically or differently H or F, particularly preferably at least one of L ¹ and L ^{2 is} F, in particular but both of the leftovers.

worin R¹, A¹ und Z¹ die in bezug auf Formel (II) angegebenen Bedeutungen annehmen, R² die in bezug auf Formel (I) angegebenen Bedeutungen annimmt und m = 1, 2 oder 3 bedeutet.The chroman derivatives of the general formulas (IIa1) to (IIa3) preferably have the following structures:

wherein R ¹ , A ¹ and Z ¹ assume the meanings given in relation to formula (II), R ² assumes the meanings given in relation to formula (I) and m = 1, 2 or 3.

worin R¹, A¹ und Z¹ die in bezug auf Formel (II) angegebenen Bedeutungen annehmen, R² die in bezug auf Formel (I) angegebenen Bedeutungen annimmt und m = 1, 2 oder 3 bedeutet.The chroman derivatives of the general formulas (IIb1) to (IIb3) preferably have the following structures:

wherein R ¹ , A ¹ and Z ¹ assume the meanings given in relation to formula (II), R ² assumes the meanings given in relation to formula (I) and m = 1, 2 or 3.

worin R¹, A¹, Z¹, m und L¹ die in bezug auf Formel (II) angegebenen Bedeutungen aufweisen. L¹ bedeutet vorzugsweise F oder CF₃. R² nimmt die in bezug auf Formel (I) angegebenen Bedeutungen an.Preferred chroman derivatives of the general formula (IIc) is the following formula (IIc1):

wherein R ¹ , A ¹ , Z ¹ , m and L ^{1 have} the meanings given in relation to formula (II). L ¹ is preferably F or CF ₃ . R ² assumes the meanings given in relation to formula (I).

worin R¹, A¹, Z¹, m und L¹ die in bezug auf Formel (II) angegebenen Bedeutungen aufweisen. L¹ bedeutet vorzugsweise F oder CF₃. R² nimmt die in bezug auf Formel (I) angegebenen Bedeutungen an.Preferred chroman derivatives of the general formula (IId) is the following formula (IId1):

wherein R ¹ , A ¹ , Z ¹ , m and L ^{1 have} the meanings given in relation to formula (II). L ¹ is preferably F or CF ₃ . R ² assumes the meanings given in relation to formula (I).

The compounds of the formula (II), (IIa) to (IId) and their sub-formulas include compounds having a ring in the mesogenic group R ¹ (-A ¹ -Z ¹ ) _m - of the subformulae a and b: R ¹ -A ¹ - a R ¹ -A ¹ -Z ¹ - b

Compounds with two rings in the mesogenic group R ¹ (-A ¹ -Z ¹ ) _m - of sub-formulas c to f: R ¹ -A ¹ -A ¹ - c R ¹ -A ¹ -A ¹ -Z ¹ - d R ¹ -A ¹ -Z ¹ -A ¹ - e R ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ - f and compounds with three rings in the mesogenic group R ¹ (-A ¹ -Z ¹ ) _m - of the subformulae g to o: R ¹ -A ¹ -A ¹ -A ¹ - g R ¹ -A ¹ -Z ¹ -A ¹ -A ¹ - h R ¹ -A ¹ -A ¹ -Z ¹ -A ¹ - i R ¹ -A ¹ -A ¹ -A ¹ -Z ¹ - j R ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ -A ¹ - k R ¹ -A ¹ -Z ¹ -A ¹ -A ¹ -Z ¹ - m R ¹ -A ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ - n R ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ - o

among them those of the sub-formulas a, b, c, d, e, g, h and i are particularly prefers.

The preferred compounds of sub-formula a include those of sub-formulas aa to ad: R ¹ -Phe- aa R ¹ -Cyc- R ¹ -Thp- ac R ¹ -Di ad

Of these, those of the following sub-formulas are particularly preferred:

The preferred compounds of sub-formula b include those of sub-formulas ba and bb: R ¹ -Phe-Z ¹ - ba R ¹ -Cyc-Z ¹ - bb

The preferred compounds of sub-formula Ic include those of sub-formulas ca to cm: R ¹ -Cyc-cyc R ¹ -Cyc-Thp- cb R ¹ -Cyc-dioctoc R ¹ -Cyc-Phe- cd R ¹ -Thp cycle R ¹ -dio-cyc-cf R ¹ -Phe-cyc- cg R ¹ -Thp-Phe- ch R ¹ -Dio-Phe- ci R ¹ -Phe-Pjcj R ¹ -pyrp R ¹ -pyd-phe- cm

Of these, those of the following sub-formulas are particularly preferred:

The preferred compounds of sub-formula d include those of sub-formulas da to dn: R ¹ -Cyc-Cyc-Z ¹ - da R ¹ -Cyc-Thp-Z ¹ -db R ¹ -Cyc-Dio-Z ¹ - dc R ¹ -Cyc-Phe-Z ¹ - dd R ¹ -Thp-Cyc-Z ¹ - de R ¹ -Dio-Cyc-Z ¹ - df R ¹ -Thp-Phe-Z ¹ - dg R ¹ -Dio-Phe-Z ¹ - ie R ¹ -Phe-Phe-Z ¹ - di R ¹ -Pyr-Phe-Z ¹ - dj R ¹ -Phe-Phe-Z ¹ - dk R ¹ -Cyc-Phe-CH ₂ CH ₂ -dm R ¹ -A ¹ -Phe-CH ₂ CH ₂ - dn

Of these, those of the following sub-formulas are particularly preferred:

The preferred compounds of sub-formula e include those of sub-formulas ea to ej: R ¹ -Cyc-Z ¹ -Cyc-ea R ¹ -Thp-Z ¹ -Cyc-eb R ¹ -A ¹ -CH ₂ CH ₂ -A ¹ - ec R ¹ -Cyc-Z ¹ -Phe- ed R ¹ -Thp-Z ¹ -Phe- ee R ¹ -A ¹ -OCO-Phe- ef R ¹ -Phe-Z ¹ -Phe- eg R ¹ -Pyr-Z ¹ -A ¹ - eh R ¹ -Pyd-Z ¹ -A ¹ - egg R ¹ -Dio-Z ¹ -A ¹ - ej

Of these, those of the following sub-formulas are particularly preferred:

The preferred compounds of sub-formula f include those of sub-formulas fa to fe: R ¹ -Phe-CH ₂ CH ₂ -A ¹ -Z ¹ - fa R ¹ -A ¹ -COO-Phe-Z ¹ - fb R ¹ -Cyc-Z ¹ -Cyc-Z ¹ - fc R ¹ -Phe-Z ¹ -Phe-Z ¹ - fd R ¹ -Cyc-CH ₂ CH ₂ -Phe-Z ¹ - fe

The preferred compounds of partial formulas g to n include those of the following partial formulas ga to ma: R ¹ -A ¹ -Cyc-ga R ¹ -A ¹ -Cyc-Phe- gb R ¹ -Phe-Phe-Phegc R ¹ -A ¹ -CH ₂ CH ₂ -A ¹ -Phe- ha R ¹ -Phe-Z ¹ -A ¹ -Phe- hb R ¹ -A ¹ -Phe-Z ¹ -Phe- ia R ¹ -Cyc-Z ¹ -A ¹ -Z ¹ -Phe- ka R ¹ -A ¹ -Z ¹ -Cyc-Phe-Z ¹ - ma

In the above preferred formulas, R ¹ , A ¹ and Z ^{1 have} the meanings given above. If A ¹ and / or Z ¹ occur several times in one of the subformulae, they may independently of one another be the same or different.

In the above, preferred formulas, R ¹ preferably denotes a linear alkyl or alkoxy radical having 1 to 7 C atoms or a linear alkenyl or alkenyloxy radical having 2 to 7 C atoms and particularly preferably a linear alkyl radical having 1 to 7 C Atoms or a linear alkenyl radical having 2 to 7 carbon atoms.

In the above preferred formulas, Z ^{1 is} preferably -CH ₂ CH ₂ -, -C≡C-, -CF ₂ CF ₂ -, -COO-, -OCO-, -CF ₂ O- or -OCF ₂ -.

If R ¹ or R ² in the formulas above and below denotes an alkyl radical, this may be straight-chain or branched. It is particularly preferably straight-chain, has 1, 2, 3, 4, 5, 6 or 7 C atoms and accordingly denotes methyl, ethyl, propyl, butyl, pentyl, hexyl or heptyl, furthermore octyl, nonyl, decyl, undecyl, Dodecyl, tridecyl, tetradecyl or pentadecyl.

If R ¹ or R ^{2 is} an alkyl radical in which one CH ₂ group has been replaced by -O-, this may be straight-chain or branched. It is preferably straight-chain and has 1 to 10 C atoms. Particularly preferably, the first CH ₂ group of this alkyl radical is replaced by -O-, so that the radical R ^{1 is} alkoxy and methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy or nonyloxy.

Furthermore, a CH ₂ group can be replaced elsewhere by -O-, so that the radical R ^{1 is} preferably straight-chain 2-oxapropyl (= methoxymethyl), 2 - (= ethoxymethyl) or 3-oxabutyl (= 2-methoxyethyl) , 2-, 3- or 4-oxapentyl, 2-, 3-, 4- or 5-oxahexyl, 2-, 3-, 4-, 5- or 6-oxaheptyl, 2-, 3-, 4-, 5 -, 6- or 7-oxo-octyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-oxanonyl, 2-, 3-, 4-, 5-, 6-, 7-, 8 - or 9-oxadecyl.

If R ¹ or R ^{2 is} an alkyl radical in which one CH ₂ group has been replaced by -CH = CH-, this may be straight-chain or branched. It is preferably straight-chain and has 2 to 10 C atoms. It therefore means vinyl, prop-1 or prop-2-enyl, but-1, 2- or but-3-enyl, pent-1, 2-, 3- or pent-4-enyl, hex-1 -, 2-, 3-, 4- or hex-5-enyl, hept-1, 2-, 3-, 4-, 5- or hept-6-enyl, Oct-1, 2-, 3- , 4-, 5-, 6- or oct-7-enyl, non-1-, 2-, 3-, 4-, 5-, 6-, 7- or non-8-enyl, Dec-1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or dec-9-enyl.

Preferred alkenyl groups are C ₂ -C ₇ -1E-alkenyl, C ₄ -C ₇ -EE-alkenyl, C ₅ -C ₇ -alkenyl, C ₆ -C ₇ -5-alkenyl, and C ₇ -6-alkenyl , particularly preferably C ₂ -C ₇ -1E-alkenyl, C ₄ -C ₇ -EE-alkenyl and C ₅ -C ₇ -alkenyl.

Examples particularly preferred alkenyl groups are vinyl, 1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hexenyl, 1E-heptenyl, 3-butenyl, 3E-pentenyl, 3E-hexenyl, 3E-heptenyl, 4-pentenyl, 4Z-hexenyl, 4E-hexenyl, 4Z-heptenyl, 5-hexenyl and 6-heptenyl. Groups of up to 5 carbon atoms are in particular prefers.

If R ^{1 is} an alkyl radical in which one CH ₂ group has been replaced by -O- and one by -CO-, these are preferably adjacent. Thus, they include an acyloxy group -CO-O- or an oxycarbonyl group -O-CO-. These are particularly preferably straight-chain and have 2 to 6 C atoms.

she Accordingly, in particular acetyloxy, propionyloxy, butyryloxy, Pentanoyloxy, hexanoyloxy, acetyloxymethyl, propionyloxymethyl, Butyryloxymethyl, pentanoyloxymethyl, 2-acetyloxyethyl, 2-propionyloxyethyl, 2-butyryloxyethyl, 3-acetyloxypropyl, 3-propionyloxypropyl, 4-acetyloxybutyl, Methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, Pentoxycarbonyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, propoxycarbonylmethyl, Butoxycarbonylmethyl, 2- (methoxycarbonyl) ethyl, 2- (ethoxycarbonyl) ethyl, 2- (propoxycarbonyl) ethyl, 3- (methoxycarbonyl) propyl, 3- (ethoxycarbonyl) propyl and 4- (methoxycarbonyl) butyl.

If R ^{1 is} an alkyl radical in which a CH ₂ group is replaced by unsubstituted or substituted -CH = CH- and an adjacent CH ₂ group by -CO-, -CO-O- or -O-CO-, so this can be straight-chain or branched. Preferably, it is straight-chain and has 4 to 13 carbon atoms. It therefore particularly preferably means acryloyloxymethyl, 2-acryloyloxyethyl, 3-acryloyloxypropyl, 4-acryloyloxybutyl, 5-acryloyloxypentyl, 6-acryloyloxyhexyl, 7-acryloyloxyheptyl, 8-acryloyloxyoctyl, 9-acryloyloxynonyl, 10-acryloyloxydecyl, methacryloyloxymethyl, 2-methacryloyloxyethyl, 3 Methacryloyloxypropyl, 4-methacryloyloxybutyl, 5-methacryloyloxypentyl, 6-methacryloyloxyhexyl, 7-methacryloyloxyheptyl, 8-methacryloyloxyoctyl and 9-methacryloyloxynonyl.

If R ¹ is a monosubstituted by CN or CF ₃ alkyl or alkenyl radical, this radical is preferably straight-chain and the substitution by CN or CF ₃ in ω-position.

If R ¹ or R ^{2 is} an alkyl or alkenyl radical which is at least monosubstituted by halogen, this radical is preferably straight-chain. Halogen is preferably F or Cl. In the case of multiple substitution, halogen is preferably F. The resulting radicals also include perfluorinated radicals. For single substitution, the fluoro or chloro substituent may be in any position, but preferably in the ω position.

Compounds of the formulas (I) to (VI) with branched wing group R ¹ or R ² may occasionally be of importance for better solubility in the customary liquid-crystalline base materials, but especially as chiral dopants, if they are optically active. Smectic compounds of this type are useful as component (s) for ferroelectric materials.

Branched groups of this type preferably contain no more than one chain branch. Preferred branched radicals R ¹ or R ² are isopropyl, 2-butyl (= 1-methylpropyl), isobutyl (= 2-methylpropyl), 2-methylbutyl, isopentyl (= 3-methylbutyl), 2-methylpentyl, 3-methylpentyl, 2 Ethylhexyl, 2-propylpentyl, isopropoxy, 2-methylpropoxy, 2-methylbutoxy, 3-methylbutoxy, 2-methylpentyloxy, 3-methylpentyloxy, 2-ethylhexyloxy, 1-methylhexyloxy and 1-methylheptyloxy.

The Formulas (I) to (VI) include both the racemates of these compounds as well as the optical antipodes and their mixtures.

Under the compounds of the formulas (I) to (VI) and the sub-formulas those are preferred in which at least one of the contained therein Rests has one of the preferred meanings given.

In the compounds of the formulas (I) to (VI) are those stereoisomers preferred in which the rings cyc and piperidine trans-1,4-disubstituted are. Those of the above formulas, one or several groups contain Pyd, Pyr and / or Dio, each enclosing the two 2,5-position isomers.

The Compounds of the general formulas (I) to (VI) can according to methods known per se, as described in the literature (e.g., in standard works such as Houben-Weyl, Methods of Organic Chemistry, Georg Thieme Verlag, Stuttgart) are described and indeed under reaction conditions suitable for the reactions mentioned are known and suitable. It can be known from, not closer here mentioned Make use of variants.

The Starting materials for the above methods are either known or can be described in Be prepared analogously to known compounds. you are thus after generally accessible Literature regulations or commercially available to obtain.

The Starting materials can optionally also be formed in situ, such that they are not isolated from the reaction mixture, but immediately on to the compounds of the general formulas (I) to (VI).

A preferred synthesis of the compounds of the general formulas (Ib) and (III) may be prepared according to literature, e.g. in Houben Weyl, Methods of Organic Chemistry, Georg Thieme Verlag, Stuttgart, New York, 4th ed. 1993, described methods.

One preferred method is the preparation of compounds of the general Formula (Ib) by ring-closing metathesis the appropriately substituted dienes 3, which according to S. Chang, R.H. Grubbs, J. Org. Chem. 1998, 63, 864-866, accessible are. The thus obtained chromenes of the general formula (III) can by catalytic hydrogenation to the chromans of the general formula (Ib) are reacted as shown in Scheme 1.

Scheme 1 Chromanesis by metathesis

alternative can do this the compounds of the invention of the general formula (Ib) also by intramolecular cyclization of diols, e.g. by S. Kelly, B.C. Vanderplas, in J. Org. Chem. 1991, 56, 1325-1327 described and shown in Scheme 2.

there receives by Aldolkondensation of Salicylaldehydderivate 4 with methyl ketones and subsequent Hydrogenation and deprotection of the ketones 5, after Reduction to alcohol 6 e.g. with sodium borohydride and by subsequent treatment with sulfuric acid in glacial acetic acid to the compounds of formula (Ib).

Scheme 2 Chromanesis by etherification

When Starting material for Compounds 3 and 4 can Salicylaldehydes are used. A possible method of manufacture This salicylaldehydes is the reaction of commercial liquid crystal precursors 7 according to the following Scheme 3.

Scheme 3 Preparation of fluorosalicylaldehydes

After transferring the Phenols 7 into a suitable derivative, e.g. MOM ether 8, can be prepared by ortho-metallation, Capture with a formamide derivative, e.g. DMF, and subsequent deprotection directly the salicylaldehydes 9 are obtained, e.g. from I.R. Hardcastle, P. Quayle, E.L.M. Ward in Tetrahedron Lett. 1994, 35, 1747-1748 described.

alternative can the phenols 7 also first halogenated and then after protection of the hydroxyl group by halogen-lithium exchange metallated and, analogously to Scheme 4, be converted to salicylaldehydes, e.g. from G.C. Finger, M.J. Gortakowski, R.H. Shiley, R.H. White in J. Amer. Chem. Soc. 1959, 81, 94-101 described and shown in Scheme 4.

Scheme 4

• a) ein Oxetan der allgemeinen Formel (VIIa) oder (VIIb)
  
  
  worin R¹, A¹, Z¹ und m die in Bezug auf Formel (II) angegebenen Bedeutungen haben, mit einem in ortho-Position metallierten Fluoraromaten in einem organischen Lösungsmittel und bei tiefen Temperaturen zu dem entsprechenden Propanolderivat der allgemeinen Formel (VIIIa) oder (VIIIb) umsetzt,
  
  worin R¹, A¹, X¹, X², X³, X⁴, Z¹ und m die in Bezug auf Formel (II) angegebenen Bedeutungen haben, und
• b) das gebildete Propanolderivat der allgemeinen Formel (VIIIa) oder (VIIIb) durch Einwirkung einer starken, nicht nucleophilen Base zum entsprechenden Chromanderivat der allgemeinen Formel II cyclisiert.

The preparation of the chroman derivatives of the general formula (II) according to the invention is preferably carried out by reacting

• a) an oxetane of the general formula (VIIa) or (VIIb)
  
  
  wherein R ¹ , A ¹ , Z ¹ and m have the meanings given in relation to formula (II), with a fluorinated in ortho position fluoroaromatics in an organic solvent and at low temperatures to the corresponding propanol derivative of the general formula (VIIIa) or (VIIIb) implements,
  
  wherein R ¹ , A ¹ , X ¹ , X ² , X ³ , X ⁴ , Z ¹ and m have the meanings given in relation to formula (II), and
• b) cyclizing the formed propanol derivative of the general formula (VIIIa) or (VIIIb) by the action of a strong, non-nucleophilic base to the corresponding chroman derivative of the general formula II.

The in this way obtained chroman derivative can be optionally by React dehydrogenation to the corresponding chromene derivative.

The reaction in step a) preferably takes place in the presence of a Lewis acid. As Lewis acids, it is possible in principle to use all compounds known to the person skilled in the art, provided that they have no acidic protons. Particularly preferred are strong Lewis acids, in particular BF ₃ etherate. In the case of particularly reactive compounds, the reaction can also be carried out without the addition of a Lewis acid.

When organic solvents can in step a) all solvents suitable for this purpose by a person skilled in the art be used. However, preferred solvents are diethyl ether, Tetrahydrofuran (THF) and dimethoxyethane (DME) and mixtures thereof.

Under low temperature is in the present application, a temperature in the range of -40 ° C to -100 ° C, preferably from -65 ° C to -85 ° C.

The preparation of the oxetanes can be carried out according to all methods known in the art. Preferably, however, starting from diols of the following formulas, which are either commercially available or are easy to prepare. A process for their preparation is described eg in the EP 0 967 261 B1 described. These diols can then be converted into oxetanes, for example, by the method described by Picard et al., Synthesis, 1981, 550-552, as shown in Scheme 5 below.

Scheme 5

Also the production of the ortho-metallated fluoroaromatics can after all The method known to those skilled in the art. Preferred methods however, are the ortho-metallation of fluoroaromatics with butyllithium (BuLi), optionally with the addition of TMEDA or similar Links to increase the reactivity of the aggregated butyllithium, Schlosser-Lochmann base or lithium diisopropylamide (LDA) respectively at low temperatures or the halogen-metal exchange of iodine fluoroaromatics or bromine fluoroaromatics with BuLi at low temperatures React 6, 1951, 339-366 or with iso-propylmagnesium chloride Temperatures in the range of -50 ° C to -10 ° C (Knochel et al., Angewandte Chemie, Int. Ed. 42, 2003, 4302-4320).

Optionally, this step can also be followed by a re-metallization. For example, lithium aromatics can be easily converted into the corresponding zinc aromatics by reaction with a ZnCl ₂ solution.

Of the ortho-metalated fluoroaromatic is then in an organic solvent reacted at low temperature with the oxetane, preferably in Presence of a Lewis acid, as shown in the two schemes 6a and 6b.

ever after used oxetane can In this way, the structurally isomeric alcohols can be obtained.

The opening of the oxetane takes place with high regioselectivity on the less substituted Page.

Scheme 6a

Scheme 6b

The formed from the ortho-metallated fluoroaromatic and the oxetane Propanol derivative is subsequently in the presence of about 1 equivalent a strong, non-nucleophilic base, e.g. Alkali hydride selected from NaH, KH, RbH or CsH, and potassium hexamethyldisilazane (KHMDS), preferably Alkali hydride, more preferably KH, in an organic solvent intramolecular cyclization. The reaction is in the following scheme 7 is shown. Preferably, this cyclization takes place in one Temperature range between 0 ° C and 78 ° C. Particularly preferred is the use of 1 to 1.5 equivalents Potassium hydride (KH) in tetrahydrofuran (THF).

Scheme 7

The If necessary, products obtained in this way may be redone be used as starting materials. In this way can be at suitable Fluorine substitution also compounds of the invention with two heterocycles as shown in the two reaction schemes 8a and 8b above.

At the cyclization reactions can further reactions follow, e.g. the functionalization of the aromatic radical by introduction of further halogen substituents, such as chlorine, bromine or iodine, or by introduction of Boronic acid groups according to literature methods.

Corresponding reaction examples show the following scheme 9:

A preferred synthesis for the construction of aryl-substituted fluoro-benzochroman derivatives of the general formula (Ia) is carried out by Suzuki coupling of corresponding boronic acids or boronic acid esters with 7-bromo-8-fluorochromans or 7-bromo-6,8-difluorochromans the following scheme 10. The required Boronic acid derivatives are prepared from bromine-substituted precursors by known methods prepared as disclosed, for example, in J. Org. Chem. 1995, 60, 7508-7510. The synthesis can be achieved by the choice of suitable starting materials the respectively desired Compounds of general formula (Ia) can be adjusted. To this Way can be, inter alia, the most preferred compounds of the sub-formulas (Ia1a) and (Ia2b).

Scheme 10

The Reactions shown are only to be considered as exemplary. The person skilled in the art can use corresponding variants of the syntheses presented as well as other suitable synthetic routes, to the compounds of the invention of the formulas (I) to (VI).

The Syntheses of various chroman derivatives according to the invention become Furthermore described by way of example in the examples.

The present invention also provides liquid-crystalline media comprising in addition to one or more compounds of the formulas (I) to (VI) according to the invention as further constituents 2 to 40, preferably 4 to 30 components. With particular preference, these media contain, in addition to one or more compounds according to the invention, 7 to 25 components. These further constituents are preferably selected from nematic or nematogenic (monotropic or isotropic) substances, in particular dere substances from the classes of azoxybenzenes, Benzylidenaniline, biphenyls, terphenyls, 1,3-dioxanes, 2,5-tetrahydropyrans, phenyl or Cyclohexylbenzoate, Cyclohexan carbonsäurephenyl- or cyclohexylester, phenyl or cyclohexyl esters of cyclohexylbenzoic, phenyl or cyclohexyl esters of Cyclohexylcyclohexancarbonsäure , Cyclohexylphenylester of benzoic acid, cyclohexanecarboxylic or Cyclohexylcyclohexancarbonsäure, Phenylcyclohexane, Cyclohexylbiphenyls, Phenylcyclohexylcyclohexane, Cyclohexylcyclohexane, Cyclohexylcyclohexylcyclohexene, 1,4-bis-cyclohexylbenzenes, 4,4'-bis-cyclohexylbiphenyls, phenyl or cyclohexylpyrimidines, phenyl or cyclohexylpyridines, phenyl - or cyclohexyldioxanes, phenyl- or cyclohexyl-1,3-dithiane, 1,2-diphenylethane, 1,2-dicyclohexylethane, 1-phenyl-2-cyclohexylethane, 1-cyclohexyl-2- (4-phenyl-cyclohexyl) -ethanes , 1-cyclohexyl-2-biphenylethane, 1-phenyl-2-cyclohexylphenylethane, optionally halogenated stilbenes, benzylphen ylether, tolans and substituted cinnamic acids. The 1,4-phenylene groups in these compounds can also be mono- or polyfluorinated.

The most important compounds which may be used as further constituents of the media according to the invention can be characterized by the formulas 1, 2, 3, 4, 5 and 6: R'-LE-R '' 1 R'-L-COO-E-R "2 R'-L-OOC-E-R "3 R'-L-CH ₂ CH ₂ -E-R "4 R'-LC≡CE-R "5 R'-L-CF ₂ OE-R "6

In the formulas 1, 2, 3, 4, 5 and 6 are L and E, the same or can be different each independently each other is a bivalent radical from the group consisting of -Phe-, -Cyc-, -Phe-Phe-, -Phe-Cyc, -Cyc-Cyc, -Pyr-, -Dio, -Thp-, -G-Phe- and -G-Cyc- and whose mirror images formed a group, with Phe unsubstituted or fluorine-substituted 1,4-phenylene, Cyc trans-1,4-cyclohexylene or 1,4-cyclohexenylene, Pyr pyrimidine-2,5-diyl or pyridine-2,5-diyl, Dio 1,3-dioxane-2,5-diyl, Thp tetrahydropyran-2,5-diyl and G 2- (trans-1,4-cyclohexyl) -ethyl, Pyrimidine-2,5-diyl, Pyridine-2,5-diyl, 1,3-dioxane-2,5-diyl or tetrahydropyran-2,5-diyl mean.

Preferably one of the radicals L and E is cyc or phe. E is preferably Cyc, Phe or Phe-Cyc. Preferably, the media of the invention contain one or more components selected from the compounds of Formulas 1, 2, 3, 4, 5 and 6 wherein L and E are selected from the group Cyc and Phe and at the same time one or more components selected from the compounds of the formulas 1, 2, 3, 4, 5 and 6, wherein one the radicals L and E selected is selected from the group Cyc and Phe and the other radical is selected from the group -Phe-Phe, -Phe-Cyc, -Cyc-Cyc, -G-Phe and -G-Cyc-, and optionally one or more components selected from the compounds of formulas 1, 2, 3, 4, 5 and 6, wherein the radicals L and E selected are from the group -Phe-Cyc, -Cyc-Cyc, -G-Phe and -G-Cyc-.

R 'and / or R "each independently represent alkyl, alkenyl, alkoxy, alkoxyalkyl, alkenyloxy or alkanoyloxy having up to 8 C atoms, -F, -Cl, -CN, -NCS, - (O) _i CH _{3 - (k + l)} F _k Cl _l , where i is 0 or 1, k and l are independently, the same or different, 0, 1, 2 or 3, but with the proviso that the sum (k + l) is 1 , 2 or 3 is.

R 'and R' 'are in a smaller subgroup the compounds of formulas 1, 2, 3, 4, 5 and 6 are each independently Alkyl, alkenyl, alkoxy, alkoxyalkyl, alkenyloxy or alkanoyloxy with up to 8 carbon atoms. The following is this smaller subgroup Group A called and the compounds are with the sub-formulas 1a, 2a, 3a, 4a, 5a and 6a. For most of these compounds R 'and R' 'are different from each other, with one of these radicals is usually alkyl, alkenyl, alkoxy or alkoxyalkyl.

In the smaller subgroup of the compounds of the formulas 1, 2, 3, 4, 5 and 6 designated as group A, E in a preferred embodiment

In a smaller subgroup of the compounds of the formulas 1, 2, 3, 4, 5 and 6 designated as group B, R "denotes -F, -Cl, -NCS or - (O) _i CH ₃ - _{(k + 1)} F _k Cl _l , where i is 0 or 1, k and 1 are independently 0, 1, 2 or 3, but with the proviso that the sum (k + l) is 1, 2 or 3. The compounds in which R "has this meaning are designated by the sub-formulas 1b, 2b, 3b, 4b, 5b and 6b. Particular preference is given to those compounds of the subformulae 1b, 2b, 3b, 4b, 5b and 6b in which R "has the meaning -F, -Cl, -NCS, -CF ₃ , -OCHF ₂ or -OCF ₃ .

In The compounds of the sub-formulas 1b, 2b, 3b, 4b, 5b and 6b R 'has the compounds of sub-formulas 1a to 6a and is preferably Alkyl, alkenyl, alkoxy or alkoxyalkyl.

In another smaller subgroup of the compounds of the formulas 1, 2, 3, 4, 5 and 6 is R "-CN. This subgroup is hereinafter referred to as group C and the compounds of this Subgroup corresponding to sub-formulas 1c, 2c, 3c, 4c, 5c and 6c described. In the compounds of sub-formulas 1c, 2c, 3c, 4c, 5c and 6c has R 'the in the compounds of the sub-formulas 1a to 6a meaning indicated and is preferably alkyl, alkenyl, alkoxy or alkoxyalkyl.

Next the preferred compounds of groups A, B and C are also others Compounds of formulas 1, 2, 3, 4, 5 and 6 with other variants the proposed substituents in use. All these substances are available by literature methods or in analogy thereto.

In addition to compounds of the formulas (I), (II), (III), (IV), (V) and / or (VI) according to the invention, the media according to the invention preferably comprise one or more compounds which are selected from groups A, B and / or C. The mass fractions of the compounds from these groups in the media according to the invention are preferably: Group A: 0 to 90%, preferably 20 to 90%, more preferably 30 to 90%; Group B: 0 to 80%, preferably 10 to 80%, more preferably 10 to 70%; Group C: 0 to 80%, preferably 5 to 80%, more preferably 5 to 50%; wherein the sum of the mass fractions of the compounds of the groups A, B and / or C contained in the respective inventive media is preferably 5 to 90% and particularly preferably 10 to 90%.

The inventive media preferably contain 1 to 40%, more preferably 5 to 30 %, the compounds of the invention. Further preferred are media containing more than 40%, especially preferably 45 to 90%, of compounds of the invention. The media preferably contain one, two, three, four or five compounds according to the invention.

mit R^a, R^b unabhängig voneinander -C_pH_2p+1 oder -OC_pH_2p+1 und p = 1, 2, 3, 4, 5, 6, 7 oder 8 sowie L¹, L² unabhängig voneinander -H oder -F,

mit m, n unabhängig voneinander 1, 2, 3, 4, 5, 6, 7 oder 8.Examples of the compounds of the formulas 1, 2, 3, 4, 5 and 6 are the compounds listed below:

with R ^a , R ^b independently of one another -C _p H _{2p + 1} or -OC _p H _{2p + 1} and p = 1, 2, 3, 4, 5, 6, 7 or 8 and L ¹ , L ² independently of one another - H or -F,

with m, n independently 1, 2, 3, 4, 5, 6, 7 or 8.

The Production of the Liquid-Crystal Mixtures According to the Invention takes place in per se usual Wise. In general, the desired Amount of components used in lesser amount in the Main component making up components solved, preferably at elevated temperature. It is also possible solutions of Components in an organic solvent, e.g. in acetone, Chloroform or methanol, to mix and the solvent after mixing to remove again, for example by distillation. Farther Is it possible, the mixtures on other conventional Species, e.g. by using premixes, e.g. Homologue mixtures or using so-called "multi-bottle" systems.

The Dielectrics can also further, known in the art and described in the literature additions contain. For example, you can 0 to 15%, preferably 0 to 10%, pleochroic dyes and / or chiral dopants are added. The individual, added Compounds are in concentrations of 0.01 to 6%, preferably from 0.1 to 3%. Here, however, the concentration data the rest Components of the liquid-crystal mixtures So the liquid crystalline or mesogenic compounds, without regard to concentration indicated these additives.

In the present application and in the following examples, the structures of the liquid crystal compounds are indicated by acronyms, wherein the transformation into chemical formulas according to following Tables A and B takes place. All radicals C _n H _{2n + 1} and C _m H _{2n + 1} are straight-chain alkyl radicals with n or m C atoms. n and m are integers, preferably 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, where n = m or n ≠ m. The coding according to Table B is self-evident. In Table A, only the acronym for the Basic body indicated. In individual cases, a code for the substituents R ^{1 *} , R ^{2 *} , L ^{1 *} and L ^{2 *} follows separately from the acronym for the main body with a dash:

preferred Mixture components are given in Tables A and B.

Table A:

Table B:

Table C:

In Table C becomes possible Specified dopants, which are preferably the mixtures of the invention be added.

Especially preference is given to mixtures according to the invention, in addition to one or more compounds of the formulas (I), (II), (III), (IV), (V) and / or (VI) two, three or more compounds selected from Tables A and / or B.

The following examples are intended to illustrate the invention without limiting it. Above and below, percentages are by weight. All temperatures are in degrees Celsius. Tg is the glass transition temperature and Klp. is the clearing point. Furthermore, K = crystalline state, N = nematic phase, Sm = smectic phase and I = isotropic phase. The data between these symbols represent the transition temperatures. Δn means optical anisotropy (589 nm, 20 ° C), Δε the dielectric anisotropy (1 kHz, 20 ° C) and γ ₁ the rotational viscosity at 20 ° C [mPas].

The Δn and Δε values of Compounds of the invention were prepared by extrapolation from liquid crystalline mixtures obtained, which is 10% from the respective compound of the invention and 90 either from the commercially available liquid crystal ZLI 4792 (Δn and positive Δε values) or the likewise commercially available liquid crystal ZLI 2857 (negative Δε values), Both Fa. Merck, Darmstadt, passed.

AIBN

Azoisobuttersäurenitril

BuLi

Butyllithium

DCM

Dichlormethan

EE

Essigester

KH

Kaliumhydrid

KHMDS

Kaliumhexamethyldisilazan

LDA

Lithiumdiisopropylamid

MCPBA

3-Chlorperoxybenzoesäure

MTBE

tert.-Butylmethylether

NBS

N-Bromsuccinimid

RT

Raumtemperatur

THF

Tetrahydrofuran

TMEDA

Tetramethylethylendiamin

The following abbreviations are used above and below:

AIBN

azoisobutyronitrile

BuLi

butyllithium

DCM

dichloromethane

EE

Essigester

KH

potassium hydride

KHMDS

potassium hexamethyldisilazane

LDA

lithium

MCPBA

3-chloroperoxybenzoic

MTBE

tert-butyl methyl ether

NBS

N-bromosuccinimide

RT

room temperature

THF

tetrahydrofuran

TMEDA

tetramethylethylenediamine

example 1

7,8-Difluoro-6- (4-trans-pentyl-cyclohexyl) -chromane

1st stage: 2-Allyloxy-3,4-difluoro-5- (4-trans-pentylcyclohexyl) benzaldehyde

3.00 g (9.67 mmol) 3,4-difluoro-2-hydroxy-5- (4-pentylcyclohexyl) benzaldehyde dissolved in 30 ml of acetone and after addition of 2.1 g (15 mmol) of potassium carbonate and 2.5 ml (30 mmol) allyl bromide heated to 60 ° C for 3 hours. After filtration, the Concentrated filtrate and the residue purified by chromatography with heptane / MTB ether (50: 1) on silica gel. You get 3.23 g (95%) of 2-allyloxy-3,4-difluoro-5- (4-pentylcyclohexyl) benzaldehyde as colorless Crystals.

2nd Step: 2-Allyloxy-3,4-difluoro-5- (4-trans-pentylcyclohexyl) -1-vinyl-benzene

3.66 g (10.0 mmol) of methyltriphenylphosphonium bromide are dissolved in 20 ml of THF submitted and under ice cooling 1.15 g (10.0 mmol) of potassium tert-butoxide added. After 10 minutes, a solution of 3.23 g (9.22 mmol) 2-Allyloxy-3,4-difluoro-5- (4-pentylcyclohexyl) benzaldehyde in 15 ml of THF is added dropwise. The cooling is removed, the mixture allowed to stir for 2 hours at room temperature and added to ice water. The aqueous phase is separated and extracted three times with MTB ether. The United organic phases are washed with water and saturated sodium chloride solution and concentrated in vacuo. The residue is taken up in heptane and with heptane / MTB ether (50: 1) over silica gel filtered. This gives 2.71 g (84%) 2-Allyloxy-3,4-difluoro-5- (4-pentylcyclohexyl) -1-vinyl-benzene as a colorless oil.

3rd stage: 7,8-Difluoro-6- (4-trans-pentyl-cyclohexyl) -2H-chromene

2.68 g 2-Allyloxy-3,4-difluoro-5- (4-trans-pentylcyclohexyl) -1-vinyl-benzene are dissolved under nitrogen in 40 ml of dichloromethane and after Add 63 mg Grubbs' catalyst Stir for 2 hours at room temperature calmly. The mixture is concentrated and the residue with n-heptane / MTB ether (50: 1) chromatographed on silica gel. This gives 930 mg (38%) of 7,8-difluoro-6- (4-pentyl-cyclohexyl) -2H-chromene as colorless crystals.

4th Step 7,8-Difluoro-6- (4-trans-pentyl-cyclohexyl) -chroman

930 mg of 7,8-difluoro-6- (4-pentylcyclohexyl) -2H-chromene are hydrogenated in ethanol on palladium-activated carbon (5%) at 1 bar and room temperature to standstill. The catalyst is filtered off, the filtrate is concentrated and the residue is recrystallized from ethanol. This gives 680 mg (79%) of 7,8-difluoro-6- (4-trans-pentyl-cyclohexyl) -chroman as colorless crystals of mp. 49 ° C.
Δε = -3.2
Δn = 0.0685

Example 2

2-ethyl-6- (4-trans-ethyl-cyclohexyl) -7,8-difluoro-chroman

1st stage: 2,3-Difluoro-4- (4-trans-ethylcyclohexyl) -6-vinyl-phenol

26.5 g (74.4 mmol) of methyltriphenylphosphonium bromide are dissolved in 150 ml THF submitted and under ice cooling a solution of 8.33 g (74.2 mmol) of potassium tert-butoxide in 50 ml of THF was added dropwise. After 2 hours, 30.0 g (67.5 mmol) of 3,4-difluoro-2- (2-methoxy-ethoxymethoxy) -5- (4-trans-ethyl-cyclohexyl) -benzaldehyde added in 50 ml of THF and over Stir at room temperature overnight calmly. The mixture is hydrolyzed with water, 100 ml of conc. hydrochloric acid Add and leave 3 hours strongly stir. Subsequently is extracted with MTBE, the combined extracts with saturated Saline washed over Dried sodium sulfate and concentrated. This gives 16.0 g (81%) of 2,3-difluoro-4- (4-trans-ethyl-cyclohexyl) -6-vinyl-phenol as a yellow oil, that for further reactions are pure enough.

2nd step: 2- (1-ethyl-allyloxy) -5- (4-trans-ethylcyclohexyl) -3,4-difluoro-1-vinyl-benzene

To a solution of 10.0 g (37.5 mmol) of 4- (4-trans-ethylcyclohexyl) -2,3-difluoro-6-vinylphenol, 11.8 g (45.0 mmol) of triphenylphosphine and 3.88 g (45.0 mmol) of 1-penten-3-ol in 150 ml of THF are 7.84 g (45.0 mmol) Diethylazodicarboxylat in 50 ml of THF was added dropwise. It is allowed 5 hours stir at room temperature and extracted with ethyl acetate. The combined organic phases become more saturated Sodium chloride solution washed and over Dried sodium sulfate. The solvent is removed in vacuo and the crude product by chromatography with n-heptane / ethyl acetate (20: 1) purified on silica gel. This gives 9.91 g (79%) of 2- (1-ethyl-allyloxy) -5- (4-trans-ethyl-cyclohexyl) -3,4-difluoro-1-vinyl-benzene as a colorless oil.

3rd stage: 2-ethyl-6- (4-trans-ethylcyclohexyl) -7,8-difluoro-2H-chromene

In Analogous to the synthesis described in Example 1, in the 3rd stage receives from 7.50 g (22.4 mmol) of 2- (1-ethyl-allyloxy) -5- (4-trans-ethyl-cyclohexyl) -3,4-difluoro-1-vinyl-benzene 5.29 g (77%) of 2-ethyl-6- (4-trans-ethylcyclohexyl) -7,8-difluoro-2H-chromene as colorless crystals.

4th stage: 2-ethyl-6- (4-trans-ethylcyclohexyl) -7,8-difluoro-chroman

5.00 g (16.3 mmol) of 2-ethyl-6- (4-trans-ethyl-cyclohexyl) -7,8-difluoro-2H-chromen are dissolved in 20 ml of THF and in the presence of palladium activated carbon catalyst until Standstill hydrogenated. The solution is filtered through silica gel and the solvent removed in vacuo. 4.38 g (87%) of 2-ethyl-6- (4-trans-ethylcyclohexyl) -7,8-difluorochromane are obtained as colorless crystals.
Δε = -5.5
Δn = 0.112

Example 3

6- (4-ethyl-phenyl) -7,8-difluoro-2-methyl-chroman

1st stage: 4- (4'-ethyl-5,6-difluoro-4-hydroxy-biphenyl-3-yl) -but-3-en-2-one

9.44 g (26.9 mmol) 4'-ethyl-5,6-difluoro-4- (2-methoxyethoxymethoxy) biphenyl-3-carbaldehyde are dissolved in 50 ml of acetone, 8.5 g 50 percent. Sodium hydroxide solution and 300 ml of water are added and 3 Stir at room temperature for days calmly. The batch is extracted with dichloromethane, concentrated and taken up in 100 ml of THF. After addition of 30 ml of conc. Hydrochloric acid turns overnight strongly touched and subsequently extracted with MTBE. The combined organic phases are with Water washed over Dried sodium sulfate and the solvent is in vacuo away. Filtration with MTBE over silica gel gives 12.2 g (92%) 4- (4'-ethyl-5,6-difluoro-4-hydroxy-biphenyl-3-yl) -but-3-en-2-one as a colorless oil.

2nd step: 4- (4'-ethyl-5,6-difluoro-4-hydroxybiphenyl-3-yl) -butan-2-one

10.1 g (33.3 mmol) of 4- (4'-ethyl-5,6-difluoro-4-hydroxy-biphenyl-3-yl) -but-3-en-2-one are dissolved in 80 ml of THF dissolved and hydrogenated on palladium-activated carbon (5%) to a standstill. Subsequently, will filtered, concentrated and the residue purified by chromatography on silica gel. This gives 7.71 g (76%) 4- (4'-ethyl-5,6-difluoro-4-hydroxy-biphenyl-3-yl) -butan-2-one as a colorless oil.

3rd step: 4'-ethyl-2,3-difluoro-5- (3-hydroxybutyl) -biphenyl-4-ol

5.8 g (19.1 mmol) of 4- (4'-ethyl-5,6-difluoro-4-hydroxybiphenyl-3-yl) -butan-2-one are dissolved in 30 ml Isopropanol dissolved, 600 mg (15.9 mmol) of sodium borohydride was added and overnight stirred at room temperature. Of the Approach is acidified carefully diluted with 50 ml of water and extracted with MTBE. The combined organic phases become washed with water and over Dried sodium sulfate. After removal of the solvent in vacuo gives 4.91 g (84%) 4'-ethyl-2,3-difluoro-5- (3-hydroxybutyl) -biphenyl-4-ol as a yellow oil, which can be implemented without further purification.

4th stage: 6- (4-ethylphenyl) -7,8-difluoro-2-methylchroman

4.5 g (14.7 mmol) of 4'-ethyl-2,3-difluoro-5- (3-hydroxybutyl) -biphenyl-4-ol are dissolved in 25 ml of glacial acetic acid and 25 ml of 50 percent strength by weight. Dissolved sulfuric acid and heated to 60 ° C for 30 minutes. The mixture is added to ice-water, neutralized with sodium hydroxide solution and extracted with MTBE. The combined organic phases are dried over sodium sulfate, concentrated and the residue is purified by chromatography on silica gel. This gives 3.05 g (72%) of 6- (4-ethyl-phenyl) -7,8-difluoro-2-methylchroman as a colorless solid.
Δε = -8.7
Δn = 0.191

Example 4

7,8-difluoro-2-methyl-6- (4-trans-propylcyclohexyl) chroman

1st stage: 2,3-difluoro-6- (3-hydroxybutyl) -4- (4-trans-propylcyclohexyl) -phenol

15.9 g (39 mmol) 4- [3,4-Difluoro-2- (2-methoxy-ethoxymethoxy) -5- (4-propyl-cyclohexyl) -phenyl] -but-3-en-2-one are dissolved in 150 ml of tetrahydrofuran on palladium activated carbon catalyst hydrogenated to standstill at 4 bar and room temperature. The solution will be filtered, with 150 ml of methanol and 15 ml of conc. Hydrochloric acid added and over Stir at room temperature overnight calmly. Subsequently the batch is added to water and extracted three times with MTB ether. The combined organic phases are washed with water and sodium sulfate dried. The solvent is removed in vacuo and the residue with heptane / MTB ether (1: 1) chromatographed on silica gel. This gives 12.3 g (77%) of 2,3-difluoro-6- (3-hydroxy-butyl) -4- (4-propyl-cyclohexyl) -phenol as a colorless oil.

2nd Step: 7,8-Difluoro-2-methyl-6- (4-trans-propyl-cyclohexyl) -chroman

2.30 g (7.05 mmol) of 2,3-difluoro-6- (3-hydroxybutyl) -4- (4-propylcyclohexyl) phenol and 1.94 g (7.40 mmol) of triphenylphosphine dissolved in 20 ml of tetrahydrofuran and 1.64 ml (8.46 mmol) of diisopropyl azodicarboxylate in 10 ml of tetrahydrofuran was added dropwise. The reaction is stirred overnight at room temperature, diluted with 30 ml of MTB ether and added to water. The organic phase is separated and extracted three times with MTB ether. The combined organic phases are washed with water and dried over sodium sulfate. The solvent is removed in vacuo and the residue is purified by chromatography using heptane / MTB ether (4: 1) on silica gel and then recrystallized from ethanol. This gives 1.3 g (55%) of colorless crystals of mp. 69 ° C.
Δε = -7.7
Δn = 0, 0759

Example 5

6- (4-trans-Ethyl-cyclohexyl) -7,8-difluoro-2-p-tolyl-chroman

1st stage: 5- (4-trans-ethyl-cyclohexyl) -3,4-difluoro-2- (1-p-tolyl-allyloxy) -benzaldehyde

In Analogous to the synthesis described in Example 2 is obtained by Mitsunobu reaction of 3,4-difluoro-2-hydroxy-5- (4-trans-pentyl-cyclohexyl) -benzaldehyde and 1-p-tolyl-prop-2-en-1-ol, the 5- (4-trans-ethyl-cyclohexyl) -3,4-difluoro-2- (1-p-tolyl-allyloxy) -benzaldehyde in 53 percent Yield as a colorless solid.

2nd step: 1- (4-trans-ethyl-cyclohexyl) -2,3-difluoro-4- (1-p-tolyl-allyloxy) -5-vinyl-benzene

By analogy with the synthesis described in Example 1 is obtained by Wittig reaction of 5- (4-trans-ethyl-cyclohexyl) -3,4-difluoro-2- (1-p-tolyl-allyloxy) benzaldehyde with methylenetriphenyl-λ ^5- phosphane, the 1- (4-trans-ethyl-cyclohexyl) -2,3-difluoro-4- (1-p-tolyl-allyloxy) -5-vinyl-benzene in 83 percent. Yield as a colorless solid.

3rd stage: 6- (4-trans-ethylcyclohexyl) -7,8-difluoro-2-p-tolyl-2H-chromen

In Analogous to the synthesis described in Example 1 provides the ring-closing metathesis of 1- (4-trans-ethyl-cyclohexyl) -2,3-difluoro-4- (1-p-tolyl-allyloxy) -5-vinyl-benzene the 6- (4-trans-ethyl-cyclohexyl) -7,8-difluoro-2-p-tolyl-2H-chromene in 69 percent. yield as colorless crystals.

4th step: 6- (4-trans-ethylcyclohexyl) -7,8-difluoro-2-p-tolylchroman

6- (4-trans-ethyl-cyclohexyl) -7,8-difluoro-2-p-tolyl-2H-chromen is hydrogenated analogously to the synthesis described in Example 1. This gives 6- (4-trans-ethyl-cyclohexyl) -7,8-difluoro-2-p-tolyl-chroman in 92 percent. Yield as colorless crystals.
Δε = -4.1
Δn = 0.1561

Example 6

trans 3- (4-ethylcyclohexyl) oxetane

wird wie folgt hergestellt:

The compound of the following formula

is made as follows:

67.4 ml of BuLi (15% in hexane) are added dropwise at 0 ° C. to a solution of 20 g of diol (11) in 100 ml of THF. After 30 minutes, a solution of 19 g of tosyl chloride in 100 ml of THF is added dropwise (exothermic, heating to about 40 ° C) and the resulting mixture stirred for 1 hour at room temperature, before further 67.4 ml BuLi are added with ice cooling. The reaction is heated at 60 ° C for 4 hours. The THF is removed on a rotary evaporator, the residue treated with water and MTBE, the organic phase separated, dried and evaporated. Purification of the residue by column chromatography (heptane / EA 6: 1) gives 11.1 g of a colorless oil (12).
Yield: 61%

Analogous Example 6 are made using the appropriate precursors the following compounds of Examples 7 and 8 are obtained:

Example 7

trans 3- (4-n-propylcyclohexyl) oxetane

• Yield: 68%

Example 8

trans 3- (4'-n-propyl-bicyclohexyl-4-yl) -oxetane

• Yield: 57%

Example 9 (Ortho-Lithiation)

trans-2- (4-ethyl-cyclohexyl) -3- (2,3,4-trifluoro-phenyl) -propan-1-ol

wird wie folgt hergestellt:

The compound of the following formula

is made as follows:

To a solution of 8.7 g of trifluorobenzene in 100 ml of THF under nitrogen at -78 ° C 40 ml of BuLi (15% in hexane) was slowly added dropwise and stirred at this temperature for 1 hour. The deep yellow solution is first injected with 7.6 g of the indicated oxetane (HPLC content 90% trans, 10% cis) and, after 15 minutes, 5.1 ml of BF ₃ etherate dropwise. When adding the BF ₃ etherate must be well cooled to keep the reaction temperature below -70 ° C. After 60 minutes of stirring at -80 ° C (TLC control, complete conversion) is quenched with 50 ml of ammonium chloride solution at -78 ° C. The thawed reaction mixture is mixed with MTBE, slightly acidified with 2N HCl, the aqueous phase is separated off and repeatedly extracted with MTBE. The combined organic phases are washed with water and saturated sodium chloride solution, dried over sodium sulfate and concentrated by rotary evaporation. Purification of the residue by chromatography over 500 ml of silica gel (eluent: toluene) gives 10.7 g of a colorless oil.

By HPLC, the content of the desired trans compound is 81%.
Yield: 71%.

Analogous Example 9 using the corresponding oxetane precursors are the following Compounds of Examples 10 to 17 were obtained. Is doing the lithiated Aromat produced by halogen-metal exchange, so is used as a solvent Diethyl ether used.

Example 18 (Cyclization)

trans-7,8-difluoro-3- (4- (ethyl) -cyclohexyl) chroman

wird wie folgt hergestellt:

The compound of the following formula

is made as follows:

To a suspension of 4.6 g of KH (30% in paraffin oil) in 500 ml of THF is slowly added dropwise under N ₂ at 40 ° C, a solution of 10 g of the alcohol (content 95%) in 250 ml of THF. After a further 2 hours at 55 ° C, the reaction is complete according to TLC control. It is quenched with 10 ml of saturated ammonium chloride solution, the majority of the THF is removed, toluene is added, the mixture is extracted with water and the organic phase is separated off. The aqueous phase is back-extracted three times with toluene. The combined organic phases are dried over sodium sulfate, concentrated by rotary evaporation and the residue is purified by column chromatography (heptane / toluene 19: 1). This gives 6.8 g of a colorless solid.
Yield: 76%

Recrystallization gives the pure trans compound:
K 82 I
Δn: 0.0729
Δε: 11.8
Clp .: -9.1 ° C

Analogously, using the corresponding precursors, the following compounds of Examples 19 to 25 are obtained:

Example 26

Under nitrogen, 1.01 g of 3,4,5-trifluorophenylboronic acid (1.1 equiv.), 2.00 g of 6-fluoro-3- (4-per pylcyclohexyl) -7-bromo-chroman (1.0 equiv.), 1.3 g sodium metaborate octahydrate (0.84 equiv.) and 141 mg bis (triphenylphosphine) palladium (II) chloride (3.5 mol%). ) suspended in 20 ml of THF and 5 ml of water. The mixture is heated with vigorous stirring at 75 ° C until the bromine-chroman is completely reacted (3 to 12 hours). After cooling, the aqueous phase is separated and back-extracted three times with MTBE. The combined organic phases are washed with sodium chloride solution, dried and concentrated by rotary evaporation. The crude product is purified by column chromatography over silica gel with heptane / toluene (6: 1) as eluent.

This gives 2.05 g of product with a content of 91%, corresponding to a yield of 82%. Recrystallization from heptane / iso-propanol gives 1.4 g of product with a content of> 99.5%.
K 102 N 115.1 I
Δn: 0.1397
Δε: 24.7
Cup .: 88.5 ° C
γ ₁ : 996 mPas

Analogous Example 26 are made using the appropriate precursors the following compounds of Examples 27 to 31 are obtained:

Example 27

• Yield: 68
• K 101 N (81,9) I
• .DELTA.n: .1305
• Δε: 27.4
• Cup .: 76.3 ° C

Example 28

• Yield: 86%
• K 100 N 180.1 l
• .DELTA.n: .1442
• Δε: 35.1
• Cup .: 165.7 ° C
• γ ₁ : 1261 mPas

Example 29

• Yield: 72
• K 106 N 166.6 I
• .DELTA.n: .1320
• Δε: 36.2
• Cup .: 155.4 ° C

Example 30

• Yield: 88%
• K 95 SmA 141 N 190 I
• .DELTA.n: .1388
• Δε: 35.8
• Cup .: 177.6 ° C

Example 31

• Yield: 71%
• K 109 N 161.5 I
• .DELTA.n: .1404
• Δε: 34.8
• Clp .: 132.0 ° C

Analogous Examples 1 to 5 are using the corresponding Precursors obtained the following compounds of Examples 32 to 2506:

Examples 32-106

Examples 107-181

Examples 182-256

Examples 257-331

Examples 332-406

Examples 407-481

Examples 482-556

Examples 557-631

Examples 632-706

Examples 707-781

Examples 782-856

Examples 857-931

Examples 932-1006

Examples 1007-1081

Examples 1082-1156

Examples 1157-1231

Examples 1232-1306

Examples 1307-1381

Examples 1382-1456

Examples 1457-1531

Examples 1532-1606

Examples 1607-1681

Examples 1682-1756

Examples 1757-1831

Examples 1832-1906

Examples 1907-1981

Examples 1982-2056

Examples 2057-2131

Examples 2132-2206

Examples 2207-2281

Examples 2282-2356

Examples 2357-2431

Examples 2432-2506

Analogous Examples 6 to 31 are using the corresponding Precursors the following compounds of Examples 2507 to 4306 receive:

Examples 2507 to 2551

Examples 2552 to 2596

Examples 2597 to 2641

Examples 2642 to 2686

Examples 2687 to 2731

Examples 2732 to 2776

Examples 2777 to 2821

Examples 2822 to 2866

Examples 2867 to 2911

Examples 2912 to 2956

Examples 2957 to 3001

Examples 3002 to 3046

Examples 3047 to 3091

Examples 3092 to 3136

Examples 3137 to 3181

Examples 3182 to 3226

Examples 3227 to 3271

Examples 3272 to 3316

Examples 3317 to 3361

Examples 3362 to 3406

Examples 3407 to 3451

Examples 3452 to 3496

Examples 3497-3541

Examples 3542 to 3586

Examples 3587 to 3631

Examples 3632 to 3676

Examples 3677 to 3721

Examples 3722 to 3766

Examples 3767 to 3811

Examples 3812 to 3856

Examples 3857 to 3901

Examples 3902 to 3946

Examples 3947 to 3991

Examples 3992 to 4036

Examples 4037 to 4081

Examples 4082 to 4126

Examples 4127 to 4171

Examples 4172 to 4216

Examples 4217 to 4261

Examples 4262 to 4306

Example 4307

7,8-Difluoro-6- (4-pentyl-cyclohexyl) -2-propylchroman

1st stage: 7,8-Difluoro-6- (4-pentylcyclohexyl) -2-propyl-2H-chromene

To Q. Wang, N.G. Finn, Org. Lett. 2000, pp. 4063-4065, 5 g (16.1 mmol) 3,4-Difluoro-2-hydroxy-5- (4-pentylcyclohexyl) benzaldehyde and 3.8 g (33.3 mmol) of E-pent-1-enylboronic acid in the presence of 0.6 ml Dibenzylamine in 80 ml of dioxane for 48 hours at 90 ° C left to stir. After adding water is extracted with MTB ether and the combined organic Phases are concentrated. The residue is chromatographed on silica gel with heptane / chlorobutane (10: 1). You get 5.8 g (86%) of 7,8-difluoro-6- (4-pentylcyclohexyl) -2-propyl-2H-chromene as a colorless oil.

2nd Step: 7,8-Difluoro-6- (4-pentylcyclohexyl) -2-propylchroman

4.8 g (13.1 mmol) of 7,8-difluoro-6- (4-pentylcyclohexyl) -2-propyl-2H-chromene are dissolved in 50 ml of THF and hydrogenated to standstill in the presence of palladium activated carbon catalyst , The solution is filtered, the solvent removed in vacuo and the residue recrystallized from ethanol. 3.4 g (71%) of 2-ethyl-6- (4-ethylcyclohexyl) -7,8-difluorochromane are obtained as colorless crystals.
T _g -53 K 55 N (15.3) I
Δε = -7.3
Δn = 0.0812

Analogous Example 4307 are made using the appropriate precursors the following compounds of Examples 4308 to 4333 are obtained.

Example 4308

7,8-difluoro-2-pentyl-6- (4-pentyl-cyclohexyl) -chromane

• K 34 N (25,2) I
• Δε = -6.8
• Δn = .0746

Example 4309

7,8-Difluoro-2- (4-pentyl-cyclohexyl) -6- (4'-propyl-bicyclohexyl-4-yl) chroman

• K 143 SmA (139) N 277.5 I
• Δε = -5.4
• Δn = 0.0712

Example 4310

7,8-Difluoro-6- (4-pentyl-phenyl) -2-propyl-chroman

• K 51 I
• Δε = -7.0
• Δn = .1407

Example 4311

7,8-difluoro-2-methyl-6- (4-butyl-cyclohexyl) -chromane

• K 75 I
• Δε = -6.8
• Δn = .0797

Example 4312

7,8-difluoro-2-methyl-6- (4'-propyl-bicyclohexyl-4-yl) chroman

• K 150 N 157 I
• Δε = -6.7
• Δn = 0.0758

Example 4313

2- (4-butyl-cyclohexyl) -6-ethoxy-7,8-difluoro-chroman

• K 100 I
• Δε = -10.8
• Δn = .0834

Example 4314

6-ethoxy-7,8-difluoro-2- (4'-propyl-bicyclohexyl-4-yl) chroman

• K 155 N 187 I
• Δn = 0.0766

Example 4315

• K 119 I

Example 4316

• K 81 SmA (75) N 177
• Δε = 31.3
• Δn = .1430

Example 4317

• K 110 N 145.7 l
• Δε = 36.9
• Δn = .1358

Example 4318

• K 102 I
• Δε = 42.3
• Δn = 0.1354

Example 4319

• K 99 SmA 126 N 174 I
• Δε = 41.6
• Δn = .1366

Example 4320

• K 89 SmA 150 N 186.6 l
• Δε = 34.3
• Δn = .1351

Example 4321

• K 98 SmA 110 N 157.8 I
• Δε = 37.9
• Δn = .1295

Example 4322

• K 88 SmA 124 N 176.8 I
• Δε = 39.1
• Δn = .1317

Example 4323

• K 121 I

Example 4324

• K 122 N 152.3 I
• Δε = 46.0
• Δn = .1406

Example 4325

• K 107 SmA (83) N 169.4 I
• Δε = 44.2
• Δn = .1404

Example 4326

• K 83 SmA 104 N 167.7 I
• Δε = 42.6
• Δn = .1392

Example 4327

• K 134 N 180.7 I
• Δε = 32.3
• Δn = 0.1498

Example 4328

• K 110 N 197.8 I
• Δε = 32.5
• Δn = .1535

Example 4329

• K 106 SmA (104) N 193.8 I
• Δε = 30.3
• Δn = .1501

Example 4330

• K 145 N 204.1 I
• Δn = .1623

Example 4331

• K 142 N 215.2 I
• Δn = .1559

Example 4332

• K 132 N 208.9 l

Example 4333

• 104 N 190.7 I

Example 4334

A liquid crystal mixture containing BCH 3F.F 10.80% BCH 5F.F 9.00% ECCP 3OCF3 4.50% ECCP 5OCF3 4.50% CBC-33F 1.80% CBC-53F 1.80% CBC-55F 1.80% PCH-6F 7.20% PCH-7F 5.40% CCP 2OCF3 7.20% CCP 3OCF3 10.80% CCP 4OCF3 6.30% CCP 5OCF3 9.90% PCH-5F 9.00% Connection of Example 26 10.00% has the following properties:
Clarification point: + 92.3 ° C
Δε: +7.3
Δn: +0.1012

Example 4335

A liquid crystal mixture containing BCH 3F.F 10.80% BCH 5F.F 9.00% ECCP 3OCF3 4.50% ECCP 5OCF3 4.50% CBC-33F 1.80% CBC-53F 1.80% CBC-55F 1.80% PCH-6F 7.20% PCH-7F 5.40% CCP 2OCF3 7.20% CCP 3OCF3 10.80% CCP 4OCF3 6.30% CCP 5OCF3 9.90% PCH-5F 9.00% Connection of Example 28 10.00% has the following properties:
Clearing point: + 97.1 ° C
Δε: +8.4
Δn: +0.1028

Example 4336

A liquid crystal mixture containing BCH 3F.F 10.80% BCH 5F.F 9.00% ECCP 3OCF3 4.50% ECCP 5OCF3 4.50% CBC-33F 1.80% CBC-53F 1.80% CBC-55F 1.80% PCH-6F 7.20% PCH-7F 5.40% CCP 2OCF3 7.20% CCP 3OCF3 10.80% CCP 4OCF3 6.30% CCP 5OCF3 9.90% PCH-5F 9.00% Compound of Example 18 10.00% has the following properties:
Clarification point: + 80.7 ° C
Δε: +5.8
Δn: +0.0916

Example 4337

A liquid crystal mixture containing PCH 3O1 9.00% PCH 3O2 9.00% CCH 3O1 29.70% CCN-47 9.90% CCN-55 9.00% CBC-33F 4.50% CBC-53F 4.50% CBC-55F 4.50% CBC 33 4.50% CBC 53 5.40% Compound of Example 18 10.00%
has the following properties:
Clarification point: + 72.0 ° C
Δε: -0.4

Claims (20)

Chroman derivatives of the general formula (I)

wherein R ^{1 is} H, halogen (F, Cl, Br, I), a linear or branched, optionally chiral, unsubstituted, a simply by CN or CF ₃ or at least one halogen-substituted alkyl radical having 1 to 15 carbon atoms or alkenyl with 2 to 15 C atoms, in which also one or more CH ₂ groups are each independently of one another denoted by -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO- O-, -CH = CH-, -CH = CF-, -CF = CH-, -CF = CF-, -C≡C- or

may be replaced so that heteroatoms are not directly linked together, R ^{2 is} H, F, Cl, NCS, CN, SF ₅ , an alkyl or alkoxy radical having 1 to 15 C atoms, an alkenyl or alkenyloxy radical having 2 to 15 C atoms, a substituted by one or more fluorine atoms alkyl or alkoxy radical having 1 to 15 carbon atoms or substituted by one or more fluorine atoms alkenyl or alkenyloxy having 2 to 15 carbon atoms, A ¹ , A ^{2 are} each independently , the same or different a) trans-1,4-cyclohexylene, wherein also one or more non-adjacent CH ₂ groups may be replaced by -O- and / or -S-, b) 1,4-phenylene, wherein one or two CH groups can be replaced by N and in which also one or more H atoms can be replaced by F, c) a radical from the group consisting of 1,4-bicyclo (2,2,2) octylene, piperidine-1, 4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl, or d) 1,4-cyclohexenylene, Z ¹ , Z ² each independently of one another, identically or differently, -O-, -CH ₂ O-, -OCH ₂ -, -CO-O-, -O-CO-, -CF ₂ O-, -OCF ₂ -, -CF ₂ CF ₂ - , -CH ₂ CF ₂ -, -CF ₂ CH ₂ -, -CH ₂ CF ₂ O-, -OCF ₂ CH ₂ -, -CH ₂ CH ₂ -, -CH = CH-, -CH = CF-, - CF = CH-, -CF = CF-, -CF = CF-CO-O-, -O-CO-CF = CF-, -C≡C- or a single bond, L ¹ , L ² , L ^{3 are} each independently each other, identically or differently, denotes H, F, Cl, NCS, CN, SF ₅ or an alkyl or alkoxy radical having 1 to 15 C atoms substituted by one or more fluorine atoms, an alkenyl or alkenyloxy radical having 2 to 3 substituted by one or more fluorine atoms 15 C atoms, preferably H, F, Cl or CN, and particularly preferably H or F, m is 0, 1, 2, 3 or 4, preferably 0, 1, 2 or 3 and particularly preferably 0, 1 or 2, and n is 1, 2, 3 or 4, preferably 1, 2 or 3 and more preferably 1 or 2, but with the proviso that the sum (m + n) = 1, 2, 3 or 4, preferably 1, 2 or 3 and more preferably 1 or 2, and the general a formula (II)

wherein R ¹ , A ¹ and Z ^{1 have} the meanings given in relation to formula (I), L ¹ , L ² , L ³ and L ⁴ each independently, identically or differently H, F, Cl, NCS, CN, SF ₅ or a substituted by one or more fluorine atoms alkyl or alkoxy radical having 1 to 15 carbon atoms, a substituted by one or more fluorine atoms alkenyl or Alkenyloxyrest having 2 to 15 carbon atoms, preferably H, F, Cl or CN, and particularly preferably H or F, wherein one of the two radicals L ² and L ³ additionally may also assume the meaning of R ² with respect to formula (I) and L ² and L ³ together also

L ⁵ and L ⁶ each independently, identically or differently H, F, Cl or CN and one of the two radicals additionally - (Z ² -A ² -) _n R ² , mean, but with the proviso that when L ⁵ and L ⁶ each independently, identically or differently, denote H, F, Cl or CN, m = 1, 2, 3 or 4, preferably 1, 2 or 3 and more preferably 1 or 2, and when one of the two radicals - (Z ² -A ² -) _{n is} R ² , m and n are each, independently of one another, identical or different, 0, 1, 2, 3 or 4, where the sum (m + n) = 1, 2, 3 or 4, preferably 1, 2 or 3, as well as chromene derivatives of the general formulas (III) and (IV)

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² , L ³ , m and n have the meanings given in relation to formula (I), and chromene derivatives of the general formulas (V) and (VI)

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² , L ³ , L ⁴ and m have the meanings given in relation to formula (II). Chroman derivatives according to claim 1, characterized in that the compounds of sub-formula (I) are compounds of the following sub-formulas:

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² , L ³ , m and n have the meanings given in relation to formula (I) in claim 1. Chroman derivatives according to claim 2, characterized in that the compounds of sub-formula (Ia) are compounds of the following sub-formulas:

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (I) in claim 1. Chroman derivatives according to Claim 2, characterized in that the compounds of the Partial formula (Ib) is a compound of the following subformulae:

wherein R ¹ , R ² , A ¹ , A ² , Z ¹ , Z ² , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (I) in claim 1. Chroman derivatives according to claim 1, characterized in that the compounds of sub-formula (II) are compounds of the following sub-formulas:

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² , L ³ , L ⁴ and m have the meanings given in relation to formula (I) and R ² with respect to formula (I) in claim 1. Chroman derivatives according to claim 5, characterized in that the compounds of sub-formula (IIa) are compounds of the following sub-formulas:

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (I) and R ² with respect to formula (I) in claim 1. Chroman derivatives of the general formulas (IIa1) to (IIa3) according to Claim 6, characterized in that they have the following structures:

wherein R ¹ , A ¹ and Z ¹ assume the meanings given in relation to formula (II) in claim 1, R ² assumes the meanings given in relation to formula (I) in claim 1 and m = 1, 2 or 3. Chroman derivatives according to claim 5, characterized in that the compounds of sub-formula (IIb) are compounds of the following sub-formulas:

wherein R ¹ , A ¹ , Z ¹ , L ¹ , L ² and L ^{3 have} the meanings given in relation to formula (I) and R ² with respect to formula (I) in claim 1. Chroman derivatives of the general formulas (IIb1) to (IIb3) according to claim 8, characterized in that they have the following structures:

wherein R ¹ , A ¹ and Z ¹ assume the meanings given in relation to formula (II) in claim 1, R ² assumes the meanings given in relation to formula (I) in claim 1 and m = 1, 2 or 3. Chroman derivatives of the formula (II) according to at least one of Claims 5 to 9, characterized in that the compounds of the formula (II) are compounds having one ring in the mesogenic group R ¹ (-A ¹ -Z ¹ ) _m - the subformulae a and b R ¹ -A ² - a R ¹ -A ² -Z ² - b is. Chroman derivatives of the formula (II) according to at least one of Claims 5 to 9, characterized in that the compounds of the formula (II) are compounds having two rings in the mesogenic group R ¹ (-A ¹ -Z ¹ ) _m - the sub-formulas c to f R ¹ -A ¹ -A ² - c R ¹ -A ¹ -A ² -Z ² - d R ¹ -A ¹ -Z ¹ -A ² - e R ¹ -A ¹ -Z ¹ -A ² -Z ² - f is. Chroman derivatives of the formula (II) according to at least one of Claims 5 to 9, characterized in that the compounds of the formula (II) are compounds with three rings in the mesogenic group R ¹ (-A ¹ -Z ¹ ) _m - the sub-formulas g to o R ¹ -A ¹ -A ¹ -A ² - g R ¹ -A ¹ -Z ¹ A ¹ -A ² - h R ¹ -A ¹ -A ¹ -Z ¹ -A ² - i R ¹ -A ¹ -A ¹ -A ² -Z ² - j R ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ -A ² - k R ¹ -A ¹ -Z ¹ -A ¹ -A ² -Z ² - m R ¹ -A ¹ -A ¹ -Z ¹ -A ² -Z ² - n R ¹ -A ¹ -Z ¹ -A ¹ -Z ¹ -A ² -Z ² - o is. Chroman derivatives according to claim 10, characterized in that the compounds of sub-formula a are compounds of the following sub-formulas

is. Chroman derivatives according to claim 11, characterized in that the compounds of sub-formula c are compounds of the following sub-formulas

is. Chroman derivatives according to Claim 11, characterized in that the compounds of sub-formula d are compounds of the following sub-formulas

is. Chroman derivatives according to claim 11, characterized in that the compounds of sub-formula e are compounds of the following sub-formulas

is. Use of chroman derivatives of the formulas (I) and (II) and chromene derivatives of the formulas (III) to (VI) according to at least one of the preceding claims as component (s) in liquid crystalline media. liquid-crystalline Medium with at least two liquid-crystalline Components, characterized in that at least one chroman and / or chromene derivative of the formulas (I) to (VI) according to at least one of the claims 1 to 16 contains. Liquid crystal display element, characterized in that it is a liquid-crystalline medium according to claim 18 contains. Electro-optical display element, characterized that it is a liquid-crystalline dielectric Medium according to claim 18 contains.