JPH06228057A - New naphthalene derivative for use in ferroelectric liquid crystal mixture - Google Patents

Abstract

PURPOSE: To obtain a new compound useful as a ferroelectric liquid crystal mixture ingredient.

CONSTITUTION: The compound of the formula (R¹ and R² are each H, 1-22C alkyl or the like; A¹ to A⁴ are each 1,4-phenylene, pyrazine-2,5-diyl or the like; M¹ to M⁴ are each -O-, -S-, -CO-, -CH=CH- or the like; k, l, m, n, o, p, q and r are each 0 or 1; or the like), e.g. 2,6-bis(4-hexyloxyphenylcarbonyloxy) napthalene is obtained. The compound of formula I is obtained e.g. by common processes such as a reaction of 2,6-dihydroxynaphthalene and 4-hexyloxybenzoic acid or the like. The compound of the formula used as a ferroelectric liquid crystal mixture derives or widens the nematic phase and gives a small switching angle in the smectic phase.

COPYRIGHT: (C)1994,JPO

Description

Detailed Description of the Invention

[0001]

The present invention relates to novel naphthalene derivatives, a process for their preparation and their use in liquid crystal mixtures.

[0002]

2. Description of the Related Art Liquid crystals are used in electro-optical switching and display devices because they have a special property of having both anisotropy and liquidity. In these devices, the electrical, magnetic, elastic and thermal properties of liquid crystals can be used to change the orientation. The optical effect is the incorporation of dye molecules having birefringence and dichroic absorption (“guest host.
Mode ”), or a method such as light scattering.

Practical demands in various fields of application continue to increase, and in order to satisfy this, new and improved liquid crystal mixtures and various mesogenic compounds of various structures are always needed. This is true both in the field of nematic liquid crystal phases and in the field of smectic liquid crystal phases.

Recently, a ferroelectric liquid crystal mixture (FLC mixture) has attracted particular attention [eg ST Lagerwall, e.
t. al., "Ferroelectric Liquid-Crystals for Display
s ", SID Symposium, Oct. Meeting 1985, San Diego, C
a. USA]. For practical use of ferroelectric liquid crystals in electro-optical displays, a chiral graded smectic phase that is stable over a wide temperature range, such as the S _C * phase, is required [RBMeyer, L. Liebe
rt, L. Strzelecki and P. Keller, J. Physique 36, L-69
(1975), etc.]. This object can be achieved by using a compound which itself forms such a phase, eg an S _C phase, or by doping a compound which does not form a chiral graded smectic phase with an optically active compound. Can [M. Brunet, C. Will
iams, Ann. Phys .3, 237 (1978), etc.].

When a ferroelectric liquid crystal mixture is used for the electro-optical component, a uniform planar alignment of the liquid crystal is required to obtain a high contrast ratio. It has been found that when the phase sequence of the liquid crystal mixture is isotropic → nematic → smectic A → smectic C with decreasing temperature, a uniform plane orientation in the S _C phase is achieved [K. Flatischler , et. al., Mol.Cryst.Liq.Cryst .13
1, 21 (1985); T. Matsumoto, et. Al., Pp. 468-470, P.
roc. of the 6th Int. Display Research Conf., Japan
Display, 30 September-2 October 1986, Tokyo, Jap
an; M. Mulakami, et. al., ibid., pp.344-347, etc.].

For ferroelectric (chiral smectic) liquid crystal mixtures, the helical pitch in the S _C * phase is large,
It is further necessary that the condition that the helix pitch be greater than 5 μm and the N * phase be very large, ie greater than 10 μm or infinite.

Optical response time τ [μ of ferroelectric liquid crystal system
s] should be as short as possible, the rotational viscosity of the system γ [mPas], spontaneous polarization Ps [nC / cm ² ]
And the following formula depending on the electric field strength E [V / m].

[0008]

[Chemical 13] Since the electric field strength E is determined by the distance between the electrodes in the electro-optical component and the applied voltage, the ferroelectric display medium must have low viscosity and high spontaneous polarization in order to obtain a short response time. I won't.

Finally, in addition to thermal, chemical and photochemical stability, a low optical anisotropy Δn (preferably about 0.1) is obtained.
3 to 0.15) and low positive or preferably negative dielectric anisotropy Δε [ST Lagerwall, et.
l., "Ferroelectric Liquid-Crystals for Displays",
SID Symposium, Oct. Meeting 1985, San Diego, Ca. U
See SA].

[0010]

All of these conditions can be met only when a mixture containing a large number of components is used. Base (or matrix) used here
It is preferable that the compound itself has a desirable phase sequence I → N → S _A → S _C as much as possible. To lower the melting point, extend the temperature range of the S _C phase and usually also the N phase, induce optical activity, complement the pitch, and balance optical and dielectric anisotropies. In addition, other ingredients are often added to the mixture. However, if possible, eg the rotational viscosity should not be increased.

Some of these components and certain mixtures are already known from the prior art. However, display manufacturers are interested in various mixtures, especially since the development of ferroelectric liquid crystal mixtures can never be considered complete. This is also because the interaction of the liquid crystal mixture with the individual components of the display device or cell (eg the alignment layer) makes it possible to conclude on the properties of the liquid crystal mixture.

The literature describes a number of naphthalene derivatives for use in liquid crystal mixtures (eg European Patent Publication No. 151294, Japanese Patent Publication No. 6).
3-246346, Japanese Patent Publication No. 01-16122
1, European Patent Publication No. 322007, West German Patent Publication No. 3906019, European Patent Publication No. 344557, US Patent No. 4886619, International Publication No. 90/0105.
6, British Patent Publication No. 2227019, Belgian Patent Publication No. 857784, Belgian Patent Publication No. 85778.
5, European Patent Publication No. 0111002, West German Patent Publication No. 2949080, British Patent Publication No. 2070593,
British Patent Publication No. 2070594, British Patent Publication No. 16
03075, British Patent Publication No. 2098986, British Patent Publication No. 2098987, British Patent Publication No. 2111.
974, West German Patent Publication 3305013, JG-A0
132978, British Patent Publication No. 2154598, Japanese Patent Publication No. 61-091141, West German Patent Publication No. 35.
10432, European Patent Publication No. 202514, European Patent Publication No. 205340, European Patent Publication No. 332409.
See No.).

[0013]

The present invention relates to novel derivatives of naphthalene and their use as liquid crystal mixtures, in particular as components of ferroelectric liquid crystal mixtures. At least one naphthalene derivative of the formula (I) is used as a component in the liquid crystal mixture.

[0014]

[Chemical 14] In the formula, symbols and subscripts have the following meanings.

R ¹ and R ² are H or have 1 to 22 carbon atoms.
Is a straight chain alkyl group, wherein one or two non-adjacent —CH ₂ — groups are —O—, —S—, —CO—, —CO.
-O-, -O-CO-, -CO-S-, -S-CO-,
-O-CO-O-, -CH = CH-,

[Chemical 15] Or -Si (CH _{3) 2} - may be substituted with, or is in any of the chiral groups below:

[Chemical 16]

Preferably, R ¹ and R ² are H or a straight-chain alkyl group having 1 to 15 carbon atoms, wherein one or two non-adjacent —CH ₂ — groups are —O—, —. S-, -C
O-, -CO-O-, -O-CO-, -O-CO-O
-, -CH = CH-,

[Chemical 17] Or -Si (CH _{3) 2} - may be substituted with, or is in any of the chiral groups below:

[Chemical 18]

Particularly preferably, R ¹ and R ² are H or a linear alkyl group having 1 to 15 carbon atoms, wherein one or two non-adjacent —CH ₂ — groups are —O—, -CO
-, -CO-O-, -O-CO-, -O-CO-O-,
-CH = CH-,

[Chemical 19] Or -Si (CH _{3) 2} - may be substituted with, or is in any of the chiral groups below:

[Chemical 20]

Very preferably, R ¹ and R ² are H or a straight-chain alkyl group having 1 to 15 carbon atoms, wherein 1
Number of -CH ₂ - groups may optionally is replaced by -O-,
Alternatively, the following chiral group:

[Chemical 21]

R ³ , R ⁴ , R ⁵ and R ⁶ , independently of one another, are H or a straight-chain or branched alkyl group having 1 to 22 carbon atoms, wherein 1 or 2 non-adjacent- CH ₂ −
The group is -O-, -S-, -CO-, -CO-O-, -O.
-CO-, -CO-S-, -S-CO-, -O-CO-
O-, -CH = CH-, -C≡C-,

[Chemical formula 22] Or -Si (CH _{3) 2} - may be substituted with or alternatively,, R ³ and R ^4, when attached as a substituent dioxolane system together - (CH _{2) 4} -
Or - (CH _{2) 5} - may be formed.

Preferably, R ³ , R ⁴ , R ⁵ and R ⁶ are
Independently of each other, H or a linear or branched alkyl group having 1 to 15 carbon atoms, wherein one or two non-adjacent —CH ₂ — groups are —O—, —S—, —CO. -, -CO-
O-, -O-CO-, -CO-S-, -S-CO-,-
O-CO-O-, -CH = CH-, -C≡C-,

[Chemical formula 23] Or -Si (CH _{3) 2} - may be substituted with or alternatively,, R ³ and R ^4, when attached as a substituent dioxolane system together - (CH _{2) 4} -
Or - (CH _{2) 5} - may be formed.

Particularly preferably, R ³ , R ⁴ , R ⁵ and R ⁶
Are, independently of each other, H or a linear or branched alkyl group having 1 to 10 carbon atoms, wherein one or two non-adjacent —CH ₂ — groups are —O—, —S—, -CO-, -C
O-O-, -O-CO-, -CO-S-, -S-CO
-, -O-CO-O-, -CH = CH-, -C≡C-,

[Chemical formula 24] Or -Si (CH _{3) 2} - may be substituted with or alternatively,, R ³ and R ^4, when attached as a substituent dioxolane system together - (CH _{2) 4} -
Or - (CH _{2) 5} - may be formed.

Very preferably, R ³ , R ⁴ , R ⁵ and R ⁶ , independently of one another, are H or a straight-chain or branched alkyl radical having 1 to 18 carbon atoms.

A ¹ , A ² , A ³ and A ⁴ are the same or different, and 1,4-phenylene in which one or two hydrogen atoms may be substituted with CH ₃ and / or CN, 1
Or two hydrogen atoms may be substituted with F, pyrazine-2,5-diyl, pyridazine-3,6-diyl, pyridine-2,5-diyl or pyrimidine-2,
5-diyl or 1,3,4-thiadiazole-
2,5-diyl, 1,3-dioxane-2,5-diyl, 1,3-dithian-2,5-diyl, 1,3-thiazole-2,4-diyl, 1,3-thiazole-2, 5
-Diyl, thiophene-2,4-diyl, thiophene-
2,5-diyl, piperazine-1,4-diyl, piperazine-2,5-diyl, naphthalene-2,6-diyl,
Bicyclo [2.2.2] octane-1,4-diyl,
It is 1,3-dioxaborinane-2,5-diyl or trans-decalin-2,6-diyl.

Preferably, A ¹ , A ² , A ³ and A ⁴ are
Identical or different, 1,4-phenylene in which one hydrogen atom may be substituted with CH ₃ , or pyrazine-2,5-diyl, pyridazine-3,6-diyl, pyridine-2,5-diyl , Pyrimidine-2,5-diyl,
1,3,4-thiadiazole-2,5-diyl, 1,3
-Dioxane-2,5-diyl, naphthalene-2,6-
Diyl or bicyclo [2.2.2] octane-1,4
-Jeil.

Particularly preferably, A ¹ , A ² , A ³ and A ⁴
Are the same or different, 1,4-phenylene in which one hydrogen atom may be replaced by CH ₃ , or pyrazine-2,5-diyl, pyridine-2,5-diyl, pyrimidine-2,5 -Diyl, 1,3,4-thiadiazole-2,5-diyl, naphthalene-2,6-diyl or 1,3-dioxane-2,5-diyl.

Very preferably, A ¹ , A ² , A ³ and A ⁴ are the same or different and 1,4-phenylene in which one hydrogen atom may be replaced by CH ₃ or pyridine- 2,5-diyl, pyrimidine-2,5-diyl or 1,3-dioxane-2,5-diyl.

M ¹ , M ² , M ³ and M ⁴ are the same or different and are --O--, --S--, --CO--, --CO--O--, --O.
-CO-, -CO-S-, -S-CO-, -O-CO-
_{O -, - O-CH 2} -, - CH 2 -CH 2 -, - CH = C
_{H -, - CH 2 CH 2} CO-O- or -O-COCH ₂
-CH ₂ - it is.

Preferably, M ¹ , M ² , M ³ and M ⁴ are
The same or different, -O-, -CO-, -CO-O-,
-O-CO -, - O- CH 2 -, - CH 2 -CH 2 -, -
_{CH = CH -, - CH 2} CH 2 CO-O- or -O-C
OCH ₂ -CH ₂ - it is.

Particularly preferably, M ¹ , M ² , M ³ and M ⁴
Are the same or different and are -O-, -CO-O-, -O-
_{CO -, - O-CH 2} -, - CH 2 -CH 2 - or -C
H = CH-.

Very preferably, M ¹ , M ² , M ³ and M ⁴ are the same or different and are --O--, --CO--O--,-.
O-CO -, - O- CH 2 - or -CH ₂ -CH ₂ -.

M ⁵ is --CH ₂ --O--, --O--CH _2- ,
It is -CO-O-, -O-CO- or a single bond.

K, l, m, n, o, p, q and r are 0
Or 1, but the sum of k + m + p + r is 1, 2 or 3. * is a chiral center.

However, compounds of the formula (I) having the following meanings are excluded:

[Chemical 25] [In the formula, each R ⁷ is independently of each other,
10 is an alkyl group or an alkoxy group, and R ⁸ is
It is an alkyl group having 1 to 10 carbon atoms, and M ⁶ is —COO.
-, - OCO -, - COCH 2 -, or -CH ₂ CH ₂
-, And s is 1 or 2].

The novel compounds of the present invention are prepared by methods known per se from the literature, for example Houven-Weyl, Methoden der Organ.
It can be produced by a method described in standard books for organic synthesis such as ischen Chemie, Georg-Thieme-Verlag, and Stuttgart.

The production is carried out under known reaction conditions suitable for the reaction. It is also possible to use various improvements known per se, which are not mentioned here in greater detail.

More specifically, for example, regarding compounds containing a 1,4-phenylene group, German Patent Publication No. 234473.
No. 2, No. 2450088, No. 2429093,
No. 2502904, No. 26366884, No. 2
Nos. 701,591 and 2,752,975; German Patent Publication No. 2641724 for compounds containing pyrimidine-2,5-diyl; German Patent Publication No. 4026233 for compounds containing pyridine-2,5-diyl.
And European Patent Publication No. 0391203; for compounds containing pyridazine-3,6-diyl, German Patent Publication No. 3231462; 1,3-dioxane-2,5-
German Patent Publication No. 294 for compounds containing diyl
4905 and 3227916; East German Patent Publication No. 160061 for compounds containing 1,3-dithian-2,5-diyl; 1,4-bicyclo [2.
2.2] For compounds containing octane-1,4-diyl, see US Pat. Nos. 4,261,652 and 4,192,192.
No. 56; N. Miyaura, T. Yanagi, A. Suzuki, Synthet for direct bonding between aromatic compounds and heterocyclic aromatic compounds.
See ic Communications 11 (1981), pp. 513-519.

If desired, the starting material may also be in situ (in s
in situ) and can be further converted to the compound of formula (I) immediately without isolation from the reaction mixture.

The compound of formula (I) of the present invention is a liquid crystal mixture,
It is particularly suitable as a component used in a ferroelectric liquid crystal mixture. In this mixture, the compound of formula (I) need not itself be liquid crystalline. The liquid crystal mixture is 0.01 to 6
0% by weight, preferably 0.1-40% by weight, particularly preferably 0.1-20% by weight, of one or more formulas
Includes compounds of (I). The other component is preferably a known compound having a nematic, cholesteric and / or smectic phase, for example, a Schiff base, biphenyl, terphenyl, phenylcyclohexane, cyclohexylbiphenyl, or a heterocyclic compound containing N-, S- or O-. (Pyrimidine, etc.), cinnamyl esters, cholesterol esters and various crosslinked polynuclear esters of p-alkylbenzoic acids with terminal polar groups.

Surprisingly, it has been found that the novel substances bring to the ferroelectric liquid-crystal mixture two highly favorable properties. First, this material is capable of inducing or spreading a nematic phase in a ferroelectric liquid crystal mixture,
This has a favorable influence on the alignment by the alignment film. Second, the novel materials change the angle (eg, intrinsic switching / tilt angle) change in the Sc * phase in an unusual and surprising way. That is, the normally observed increase in switching angle / tilt angle with decreasing temperature in the Sc * phase can be reduced by this material, or even reversed at lower temperatures to a decrease in angle. This has a very positive effect on use. This is because the polarizer / analyzer is usually fixed in its position in the display and changes in switching angle with temperature basically result in changes in contrast and brightness.

Further, in the Sc * phase, for a relatively low switching angle at a relatively low temperature (that is, a smooth change of the switching angle with temperature), the response speed at such a temperature is decreased due to the decrease of the angle. An increase is also observed.

Furthermore, the compounds of formula (I) have a wide range of applications. These compounds, depending on the choice of substituents,
It can be used mainly as a basic material for forming a liquid crystal phase, a smectic phase, particularly a ferroelectric smectic phase. However, the compounds of formula (I) also have other properties, for example for changing the dielectric anisotropy, optical anisotropy, viscosity, spontaneous polarization, phase range, tilt angle and pitch of this type of dielectric, etc. It can also be added to the liquid crystal basic material consisting of a compound of a kind.

The mixture according to the invention comprises a display element, a switching element, a light modulator, an image processing element,
It can be used as an element for signal processing, or an electro-optical element or a completely optical element in the field of general nonlinear optics.

Hereinafter, the present invention will be described in more detail with reference to examples.

[0044]

[Examples] For ferroelectric liquid crystal mixtures, the method of H. Diamant et al. (Rev. Sci. Instr. 28, 30 (1
957)), the spontaneous polarization value Ps (nC / cm ² ) was measured at 25 ° C. using a measuring cell having an electrode distance of 10 μm and having no alignment film.

The critical pulse area (CPA) is
It was decided as follows. A rectangular electrical pulse of appropriate voltage (polarity) and duration for a given cell thickness will result in one stable switching state if the voltage and / or pulse duration is high enough. Permanently switch to the switching state of. CPA is 5
It is obtained as the product of the pulse duration of 0 μs, the minimum voltage required for completely permanent switching, and the reciprocal of the cell density (T = 25 ° C.).

The switching angle 2Θ _eff was determined at 25 ° C. from the difference between the angles of the two preswitching states after electrode short circuit. CPA and 2Θ _eff measurements were made using a glass test cell about 1.8 μm thick with an ITO electrode and a rubbed polyvinyl alcohol (PVA) alignment film. The filled cells were switched by a rectangular pulse (IOH ₂ ) for 1 minute at 25 ° C. in an electric field of 15 V / μm before performing the actual measurements.

Therefore, the characteristic switching angle (twice the tilt angle) is determined from the switching state when addressing with a rectangular electric field of 10 V / μm, 10 Hz.

The phase transition temperature was determined by using a polarization microscope and changing the texture with heating and cooling. On the other hand, the melting point was measured using a DSC device. Each of the following phases: Isotropic (I) Nematic (N or N *) Smectic A (S _A ) Smectic C (S _C or S _C *) The phase transition temperature between crystals (X) is expressed in ° C. Values are shown between phase symbols in the phase series. The first data shows the phase transition temperature when going to the isotropic phase by heating, and when the phase transition temperature during cooling is significantly different from that during heating, the temperature is shown below.

[0049]

【Example】

(Example 1) 6-decyloxynaphthalene-2-carboxylic acid 4-
(5-octylpyrimidin-2-yl) phenyl 2- (4-hydroxyphenyl) -5-octylpyrimidine 0.60 g (2 mmol), 6-decyloxynaphthalene-2-carboxylic acid 0.66 g (2 mmol),
N, N'-dicyclohexylcarbodiimide 0.41 g
(2 mmol) and 0.02 g (0.2 mmol) of 4-N, N'-dimethylaminopyridine were stirred in 25 ml of dichloromethane at room temperature for 4 hours. next,
The mixture is filtered, the filtrate evaporated and the product chromatographed on silica gel (eluent dichloromethane).
And then recrystallized from n-hexane. 0.83 g of product was obtained.

[0050]

[Chemical formula 26] This compound had the following phase sequence: X ₁ 74 X ₂ 92 N 192 I 192 N
86 S _C 33 X

(Example 2) 2,6-bis (4-hexyloxyphenylcarbonyloxy) naphthalene was produced from 2,6-dihydroxynaphthalene and 4-hexyloxybenzoic acid in the same manner as in Example 1. .

[0052]

[Chemical 27] This compound had the following phase sequence: X 144 N 262 I

Example 3 6-Butylnaphthalene-2-carboxylic acid 4- (4-pentoxyphenoxycarbonyl) phenyl 6-butylnaphthalene-2-carboxylic acid and 4-hydroxybenzoic acid 4-pentoxy were prepared. The same procedure as in Example 1 was carried out from phenyl.

[0054]

[Chemical 28] This compound had the following phase sequence: X 137 N 255 I 255 N 121 X

(Example 4) 6-Butylnaphthalene-2-carboxylic acid 4- (4-hexyloxyphenoxycarbonyl) phenyl The preparation was carried out using 6-butylnaphthalene-2-carboxylic acid and 4-hydroxybenzoic acid 4-hexyloxy. The same procedure as in Example 1 was carried out from phenyl.

[0056]

[Chemical 29] This compound had the following phase sequence: X 118 N 252 I 252 N 103 X

(Example 5) 6-Butylnaphthalene-2-carboxylic acid 4- (4-heptyloxyphenoxycarbonyl) phenyl The production was carried out using 6-butylnaphthalene-2-carboxylic acid and 4-hydroxybenzoic acid 4-heptyloxy. The same procedure as in Example 1 was carried out from phenyl.

[0058]

[Chemical 30] This compound had the following phase sequence: X 117 N 245 I 245 N 97 X

(Example 6) 6-Butylnaphthalene-2-carboxylic acid 4- (4-butoxyphenoxycarbonyl) -3-methylphenyl The production was conducted using 6-butylnaphthalene-2-carboxylic acid and 4-hydroxy-3-carboxylic acid. The same procedure as in Example 1 was carried out from 4-butoxyphenyl methylbenzoate.

[0060]

[Chemical 31] This compound had the following phase sequence: X 110 N 230 I 230 N 87 X

(Example 7) 6-Butylnaphthalene-2-carboxylic acid 4- (5-hexyl-1,3-dioxan-2-yl) -3-methylphenyl The production was 6-butylnaphthalene-2-carboxylic acid. Acid and 4- (5-hexyl-1,3-dioxan-2-yl)
Example 1 from -1-hydroxy-3-methylbenzene
I went in the same way.

[0062]

[Chemical 32] This compound had the following phase sequence: X 103 N 166 I 166 N 28 X

(Example 8) 6-butylnaphthalene-2-carboxylic acid 4- (5-hexyl-1,3-dioxan-2-yl) -phenyl The preparation was carried out using 6-butylnaphthalene-2-carboxylic acid and 4 -(5-hexyl-1,3-dioxan-2-yl)
The same procedure as in Example 1 was performed using -1-hydroxybenzene.

[0064]

[Chemical 33] This compound had the following phase sequence: X 118 N 215 I 215 N 72 X

Example 9 5-octyloxy-2- (6-octyloxynaphthalen-2-yl) pyrimidine triphenylphosphine 1.10 g (4.28 mmo)
l) together with 0.7 ml (4.28 mmol) diethylazodicarboxylic acid in 20 ml tetrahydrofuran,
Stir for 30 minutes at 0 ° C. Next, 0.7 ml (4.28 mmol) of 1-octanol and 5-hydroxy-2- (6-octyloxynaphthalen-2-yl).
Pyrimidine 1.00 g (2.85 mmol) was added and the mixture was stirred at room temperature for 6 hours. After removing the solvent by distillation, the crude product is chromatographed on silica gel (eluent dichloromethane: ethyl acetate = 95: 5).
And then recrystallized from n-hexane. 0.96 g of product was obtained.

[0066]

[Chemical 34] This compound had the following phase sequence: X 93 S _C 105 S _A 111 N 129 I

Example 10 [(2S, 3S) -3-Butyloxiran-2-yl]
Methyl 2- (6-octyloxynaphthalen-2-yl) pyrimidin-5-yl ether The synthesis is 5-hydroxy-2- (6-octyloxynaphthalen-2-yl) pyrimidine and (2S, 3S).
The same procedure as in Example 9 was carried out from -3-butyloxiran-2-ylmethanol.

[0068]

[Chemical 35] This compound had the following phase sequence: X 85 S _C * 128.4 S _A 130.5 N * 141 IN * 130.6 S
_A 128.4 S _C * 55 X [α] _D ²⁰ = -15.67 °

Example 11 4-decyloxybenzoic acid 6-[(2S, 3S) -3
-Butyloxiran-2-yl] methoxynaphthalene-
2-yl Synthesis was performed in the same manner as in Example 9 from 6-hydroxynaphthalen-2-yl 4-decyloxybenzoate and (2S, 3S) -3-butyloxiran-2-ylmethanol.

This compound had the following phase sequence: X 134 S _C * 170 N * 221 I

(Example 12) Cyclopropanecarboxylic acid 2- (6-octyloxynaphthalen-2-yl) pyrimidin-5-yl Production was carried out using cyclopropanecarboxylic acid and 5-hydroxy-2- (6-octyloxynaphthalene). -2-yl)
The same procedure as in Example 1 was performed using pyrimidine.

[0072]

[Chemical 36] This compound had the following phase sequence: X129I114X

(Example 13) 5-Cyclopropylmethoxy-2- (6-octyloxynaphthalen-2-yl) pyrimidine The preparation was carried out using cyclopropylmethanol and 5-hydroxy-2- (6-octyloxynaphthalene-2-). Ill)
The same procedure as in Example 9 was performed using pyrimidine.

[0074]

[Chemical 37] This compound had the following phase sequence: X 107 I 101 N 90 X

(Example 14) 6-octyloxynaphthalene-2-carboxylic acid 4-
(4-Heptyloxyphenoxycarbonyl) phenyl was produced in the same manner as in Example 1 from 6-octyloxynaphthalene-2-carboxylic acid and 4-heptyloxyphenyl 4-hydroxybenzoate.

[0076]

[Chemical 38] This compound had the following phase sequence: X 107 (70) S _C 136 S _A 217 N
237 I

(Example 15) 6-octylnaphthalene-2-carboxylic acid 4-butylcyclohexyl Production was carried out in the same manner as in Example 1 from 6-octylnaphthalene-2-carboxylic acid and 4-butylcyclohexanol. .

[0078]

[Chemical Formula 39] This compound had the following phase sequence: X52N69IN-5X.

USE EXAMPLE 1 The substance S1 from Example 1 was added to the mixture M1 at 5 mol%. Mixture M1 has the following composition (mol%):

[Chemical 40] The phase series and other measurements of the mixtures M1 and M1 plus 5 mol% S1 are shown in the table below. It can be seen that the nematic phase is induced. At the same time, the melting point is also improved.

[0080]

[Table 1] M1 phase series: X -10 S_C 52 S_A 74 I 74 S_A 52 S_C -1
0 X Ps_sat: 43 nC / cm² M1 + 5 mol% S1 phase series: X -12 S_C* 45 S_A 72 N * 78 I 47 N * 7
2 S_A 45 S_C* -12 XPs_sat: 35 nC / cm²  Unique switch for M1 and M1 + 5 mol% S1
A graph of the tang angle is shown in FIG.

It is clear that the new substances have a great effect even at low concentrations. This is preferable because there is less change in other properties such as viscosity.

USE EXAMPLE 2 Material S8 from Example 8 was added to mixture M2 at 5 mol%. Mixture M2 has the following composition (mol%):

[Chemical 41] The phase series and intrinsic switching angles are shown in the table below for M2 and M2 + 5 mol% S8.

[0083]

TABLE 2 M2-phase _{sequence: X 2 S C * 63 S} A 69 N * 86 J 86 N * 69 S A 63 S C * -10 X M2 + 5 mol% S8 phase sequence: X -2 S _C * 61 S _A 62 N * 85 J 85 N * 62 S _A 61 S _C * -15 X Specific 2Θ (°) 40 ° 25 ° 0 ° M2 48.5 ° 52.5 ° 56 ° M2 + 5 mol% S8 53 ° 56. It can be seen that the nematic phase spreads significantly at the expense of the 5 ° 58 ° S _A phase, while the S _A / S _C * transition temperature remains virtually unchanged. This is very favorable for the operating temperature range. At the same time, the angles in the temperature range 0 ° C. to 40 ° C. (typical operating temperature range) are significantly changed by the new substances.

[Brief description of drawings]

FIG. 1 shows a graph of intrinsic switching angle for M1 and M1 + 5 mol% S1.

[Explanation of symbols]

 2Θ: Inherent switching angle T: Temperature

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication C07C 327/28 7106-4H 327/32 7106-4H C07D 239/26 8615-4C 239/34 8615- 4C 303/28 303/48 319/06 405/12 239 7602-4C C09K 19/32 9279-4H 19/34 9279-4H 19/42 9279-4H 19/46 9279-4H G02F 1/13 500 (72) Inventor Jaffia Manello Federal Republic of Germany Day-65931 Frank Furt am Main, Sintlinger Bernstrasse 163 (72) Inventor Hubert Schlosser Federal Republic of Germany Day 61479 Glashütten / Taunus, Im Hein 2

Claims (7)

[Claims] 1. A compound of formula (I): [Wherein the symbols and subscripts have the following meanings: R ¹ and R ² are H or a straight-chain alkyl group having 1 to 22 carbon atoms, wherein 1 or 2 non-adjacent —CH ₂ — The base is
-O-, -S-, -CO-, -CO-O-, -O-CO
-, -CO-S-, -S-CO-, -O-CO-O-,
-CH = CH-, Or may be substituted with —Si (CH ₃ ) ₂ — or is one of the following chiral groups: embedded image R ^3, R ^4, R ⁵ and R ^6, independently of one another, are H or a straight-chain or branched alkyl group having 1 to 22 carbon atoms, wherein one or two non-adjacent -CH ₂ - The group is -O-,
-S-, -CO-, -CO-O-, -O-CO-, -C
OS-, -S-CO-, -O-CO-O-, -CH =
CH-, -C≡C-, Or -Si (CH _{3) 2} - may be substituted with or alternatively,, R ³ and R ^4, when attached as a substituent dioxolane system together - (CH _{2) 4} -
Alternatively, — (CH ₂ ) ₅ — may be formed; A ¹ , A ² , A
³ and A ⁴ are the same or different and 1,4-phenylene in which 1 or 2 hydrogen atoms may be substituted with CH ₃ and / or CN, 1 or 2 hydrogen atoms are substituted with F Optionally pyrazine-2,5-diyl,
Pyridazine-3,6-diyl, pyridine-2,5-diyl or pyrimidine-2,5-diyl, or 1,
3,4-thiadiazole-2,5-diyl, 1,3-dioxane-2,5-diyl, 1,3-dithian-2,5
-Diyl, 1,3-thiazole-2,4-diyl, 1,
3-thiazole-2,5-diyl, thiophene-2,4
-Diyl, thiophene-2,5-diyl, piperazine-
1,4-diyl, piperazine-2,5-diyl, naphthalene-2,6-diyl, bicyclo [2.2.2] octane-1,4-diyl, 1,3-dioxaborinane-2,
5-diyl or trans-decalin-2,6-diyl; M ¹ , M ² , M ³ and M ⁴ are the same or different and are —O—, —S—, —CO—, —CO—O—. , -O-
CO-, -CO-S-, -S-CO-, -O-CO-O
_{-, - O-CH 2 -} , - CH 2 -CH 2 -, - CH = CH
_{-, - CH 2 CH 2 CO} -O- or -O-COCH ₂ -
CH ₂ —; M ⁵ is —CH ₂ —O—, —O—CH.
_2- , -CO-O-, -O-CO- or a single bond; k, l, m, n, o, p, q and r are 0 or 1
However, the sum of k + m + p + r is 1, 2 or 3
* Is a chiral center; provided that formula (I) has the following meanings: (In the formula, each R ⁷ independently of one another has 1 to 1 carbon atoms.
10 is an alkyl group or an alkoxy group, and R ⁸ is
It is an alkyl group having 1 to 10 carbon atoms, and M ⁶ is —COO.
-, - OCO -, - COCH 2 -, or -CH ₂ CH ₂
-And s is 1 or 2) are excluded]. 2. A compound according to claim 1, wherein the symbols and subscripts have the following meanings: R ¹ and R ² are H or 1 carbon atoms.
A linear alkyl group of 15, wherein one or two non-adjacent -CH ₂ - groups, -O -, - S -, - CO-,
-O-CO-, -O-CO-O-, -CH = CH-, Or optionally substituted with —Si (CH ₃ ) ₂ — or any of the following chiral groups: embedded image R ^3, R ^4, R ⁵ and R ⁶ are each independently a linear or branched alkyl group H or 1 to 15 carbon atoms, wherein one or two non-adjacent -CH ₂ - The group is -O-,
-S-, -CO-, -CO-O-, -O-CO-, -C
OS-, -S-CO-, -O-CO-O-, -CH =
CH-, -C≡C-, Or -Si (CH _{3) 2} - may be substituted with or alternatively,, R ³ and R ^4, when attached as a substituent dioxolane system together - (CH _{2) 4} -
Alternatively, — (CH ₂ ) ₅ — may be formed; A ¹ , A ² , A
³ and A ⁴ are the same or different and one hydrogen atom is C
1,4-phenylene optionally substituted with H ₃ , or pyrazine-2,5-diyl, pyridazine-3,6
-Diyl, pyridine-2,5-diyl, pyrimidine-
2,5-diyl, 1,3-dioxane-2,5-diyl, naphthalene-2,6-diyl or bicyclo [2.
2.2] Octane-1,4-diyl; M ¹ , M ² ,
M ³ and M ⁴ are the same or different and are —O—, —S—,
-CO -, - CO-O - , - O-CO -, - O-CH 2
_{-, - CH 2 -CH 2 -} , - CH = CH -, - CH 2 CH 2
CO—O— or —O—COCH ₂ —CH ₂ —: with the exception of claim 1. 3. A compound according to claim 1, wherein the symbols and subscripts have the following meanings: R ¹ and R ² are H or have 1 carbon atom.
To 15 straight chain alkyl groups, wherein one or two non-adjacent —CH ₂ — groups are —O—, —CO—, —CO—.
O-, -O-CO-, -O-CO-O-, -CH = CH
-, Or optionally substituted with —Si (CH ₃ ) ₂ — or any of the following chiral groups: embedded image R ^3, R ^4, R ⁵ and R ^6, independently of one another, are H or a straight-chain or branched alkyl group having 1 to 10 carbon atoms, wherein one or two non-adjacent -CH ₂ - The group is -O-,
-S-, -CO-, -CO-O-, -O-CO-, -C
OS-, -S-CO-, -O-CO-O-, -CH =
CH-, -C≡C-, Or -Si (CH _{3) 2} - may be substituted with or alternatively,, R ³ and R ^4, when attached as a substituent dioxolane system together - (CH _{2) 4} -
Alternatively, — (CH ₂ ) ₅ — may be formed; A ¹ , A ² , A
³ and A ⁴ are the same or different and one hydrogen atom is C
1,4-phenylene optionally substituted with H ₃ , or pyrazine-2,5-diyl, pyridine-2,5-
Diyl, pyrimidine-2,5-diyl, 1,3,4-thiadiazole-2,5-diyl, naphthalene-2,6-
Diyl or 1,3-dioxane-2,5-diyl; M ¹ , M ² , M ³ and M ⁴ are the same or different;
O -, - CO-O - , - O-CO -, - O-CH 2 -,
-CH ₂ -CH ₂ - or -CH = CH-; however,
The exception of claim 1 is retained. 4. A compound according to claim 1, wherein the symbols and subscripts have the following meanings: R ¹ and R ² are H or C 1
~ 15 straight chain alkyl groups wherein one -CH ₂
The -group may be substituted with -O- or is a chiral group as follows: R ³ , R ⁴ and R ⁵ are, independently of each other, H or a linear or branched alkyl group having 1 to 8 carbon atoms; A ¹ ,
A ² , A ³ and A ⁴ are the same or different, and 1,4-phenylene in which one hydrogen atom may be substituted with CH ₃ , or pyridine-2,5-diyl, pyrimidine-2,5 -Diyl or 1,3-dioxane-2,5-
Diyl; M ¹ , M ² , M ³ and M ⁴ are the same or different and are —O—, —CO—O—, —O—CO—, —O—.
CH ₂ — or —CH ₂ —CH ₂ —; with the exception of claim 1. 5. A ferroelectric liquid crystal mixture containing at least one compound according to claim 1. 6. Ferroelectric liquid crystal mixture according to claim 5, comprising 0.01 to 60% by weight of at least one compound of formula (I). 7. A switching and / or display element comprising an outer plate, an electrode, at least one polarizer, at least one alignment film and a liquid crystal medium, said liquid crystal medium being ferroelectric according to claim 5 or 6. A device characterized by being a liquid crystalline mixture.