JP3194399B2 - Phenylpyrimidine derivative having optically active lactone ring and liquid crystal composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel phenylpyrimidine derivative having an optically active lactone ring, a liquid crystal material using the same, a process for producing the same, and a synthetic intermediate thereof. The present invention relates to a dielectric liquid crystal display material.

[0002]

2. Description of the Related Art Liquid crystal display devices are widely used at present because of their excellent features (low-voltage driving, low power consumption, thin display, use in bright places, and no eyestrain). However, the TN type, which is the most common display method, has a very slow response as compared with other light-emitting display methods such as a CRT, and obtains display memory (memory effect) when the applied electric field is cut off. Therefore, there are many restrictions on application to moving images such as an optical shutter and a printer head that require a high-speed response, and a television that requires a time-division drive, and the display method is not always suitable.

Recently, a display method using a ferroelectric liquid crystal has been reported.
Since a high-speed response of 000 times and a memory effect can be obtained, it is expected as a next-generation liquid crystal display device, and research and development are being actively conducted at present.

The liquid crystal phase of the ferroelectric liquid crystal belongs to a tilt type chiral smectic phase. Among them, a chiral smectic C (hereinafter abbreviated as SC ^* ) phase has the lowest viscosity and is most desirable.

Although a large number of liquid crystal compounds exhibiting the SC ^* phase have already been synthesized and studied, the following conditions for use as a ferroelectric liquid crystal display element, ie, (a) the SC ^* phase can be used over a wide temperature range including room temperature. (B) to have an appropriate phase series on the high temperature side of the SC ^* phase and to have a large helical pitch to obtain good orientation, (c) to have an appropriate tilt angle, D) There is no known compound that satisfies the following requirements: (e) low viscosity, (e) spontaneous polarization is large to some extent, and (f) high-speed response. Therefore, a mixture of several or more compounds and SC ^*
It must be used as a liquid crystal composition showing a phase (hereinafter, abbreviated as SC ^* liquid crystal composition).

[0006] As a method for preparing a SC ^* liquid crystal composition, a smectic C (hereinafter, referred to as SC) comprises an achiral compound.
The method of adding a dopant composed of an optically active compound as a so-called chiral dopant to a base liquid crystal (hereinafter abbreviated as SC base liquid crystal) exhibiting a phase can provide a composition having a lower viscosity and a higher speed. Most common because it allows a response.

The compound used as a chiral dopant alone does not necessarily need to show an SC ^* phase, and does not need to show even a liquid crystal phase, but it can induce sufficient spontaneous polarization in a liquid crystal composition with a small amount of addition, It is necessary to exhibit properties such as a sufficiently large spiral pitch induced as a dopant.

In order to induce a large spontaneous polarization as a chiral dopant, a group having a strong dipole moment needs to be fixed as close to the central skeleton (core) and asymmetric carbon of the compound molecule as possible. That is already known. Based on such an idea, the present inventors have made general formula (IV)

[0009]

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Wherein R ³ represents an alkyl group or an alkoxyl group; ring B represents a 1,4-phenylene group or a trans-1,4-cyclohexylene group which may be substituted by a fluorine atom; ⁴ represents an alkyl group.) To synthesize an optically active lactone derivative represented by the formula:
By adding a small amount of this compound to SC matrix liquid crystal,
SC that induces sufficiently large spontaneous polarization and has high-speed response
^* It has been found that a liquid crystal composition can be prepared.
(16 pages of liquid crystal discussion proceedings, 44 pages,
-286673)

[0011]

As described above, it has been known that an optically active lactone derivative has an excellent property as a chiral dopant. There was no room for improvement.

There are many known skeletons of liquid crystal compounds having a tendency to exhibit an SC (or SC ^* ) phase. Typical examples thereof include an ester type such as phenyl benzoate and a phenylpyrimidine type. I can give it. When the two are compared, the phenylpyrimidine type is lower in viscosity, so that it is often used as a constituent material of SC parent liquid crystals.

Therefore, it is considered that the optically active compound for a chiral dopant is preferably a phenylpyrimidine type skeleton rather than an ester type in order to reduce the viscosity of the composition.

An object of the present invention is to provide a phenylpyrimidine derivative having an optically active lactone ring, and to provide a phenylpyrimidine derivative containing the same and having a higher response speed than a conventional composition containing an optically active lactone derivative. It is an object of the present invention to provide a possible ferroelectric liquid crystal display material.

[0015]

According to the present invention, there is provided a compound represented by the general formula (I):

[0016]

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(Wherein R ¹ represents a fluorine atom or an alkyl group having 1 to 18 carbon atoms which may be substituted by an alkoxyl group having 1 to 10 carbon atoms, preferably 4 to 12 carbon atoms) X represents a linear alkyl group.
Represents a single bond or -O-, and m represents 0 or 1.
Ring A represents a 1,4-phenylene group or a trans-1,4-cyclohexylene group which may be substituted by one or two fluorine atoms, preferably a 1,4-phenylene group. R ² represents an alkyl group having 1 to 10 carbon atoms, preferably a linear alkyl group having 1 to 10 carbon atoms, and the asymmetric carbon atoms at the 2- and 4-positions of the lactone ring are each independently In addition, the (R) or (S) configuration is preferred, and the (R) or both (S) configuration is preferred at both the 2- and 4-positions. The present invention provides a phenylpyrimidine derivative having an optically active lactone ring represented by the formula:

The present invention also provides a liquid crystal composition containing the optically active compound represented by the general formula (I).
The liquid crystal composition of the present invention contains at least one of the compounds of the above general formula (I) as a constituent component. In particular, for a ferroelectric liquid crystal display, an SC matrix liquid crystal as a main component contains: S containing at least one compound of the above general formula (I) as part or all of a chiral dopant
C ^* liquid crystal compositions are most desirable.

The compound of the general formula (I) of the present invention is
By adding a small amount to a nematic liquid crystal, a so-called reverse domain as a TN type liquid crystal can be prevented, or
It can also be used for applications such as TN type liquid crystal.

Further, the present invention also provides a method for producing the compound of the formula (I), and the method for producing the compound will be described below. First, the general formula (II)

[0021]

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(Wherein Y represents a halogen atom, preferably a bromine atom, and the absolute configuration of R ² and the asymmetric carbon atom at the 2- and 4-positions of the lactone ring is represented by the general formula (I) An optically active lactone derivative represented by the following general formula (III):

[0023]

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(Wherein R ¹ , X, m and ring A have the same meanings as in formula (I), and Z represents a halogen atom, but preferably represents a chlorine atom). By reacting with a derivative in the presence of zinc and a nickel complex, the compound represented by the general formula (I)
Can be obtained.

Here, as the nickel complex, for example,
Dibromobis (triphenylphosphine) nickel (I
I) and the like are preferred. Here, the optically active lactone derivative of the general formula (II) used as a raw material is also a novel compound, and is not limited to the compound of the general formula (I).
It is also useful as a production intermediate for other optically active lactone derivatives, and the present invention also provides this compound.

The compound of the general formula (II) is, for example,
It can be manufactured as follows. General formula (V)

[0027]

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(Wherein Y has the same meaning as in the above general formula (II)), a strong base is used as a dianion, and this is represented by the general formula (VI)

[0029]

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(Wherein R ² has the same meaning as in formula (I), and * represents that the carbon is an optically active asymmetric carbon). Then, the obtained optically active 4-hydroxycarboxylic acid derivative is cyclized in the presence of an acid catalyst to give a compound of the general formula (II).

Here, some of the optically active oxirane derivatives of the general formula (VI) are commercially available, and compounds that are not commercially available can be easily synthesized from commercially available optically active epichlorohydrin.

The compounds of the general formula (I) of the present invention can be obtained as described above. Specific compounds belonging to these compounds include phase transition temperature such as melting point, infrared absorption spectrum (IR), and nucleus. It can be confirmed by means such as a magnetic resonance spectrum (NMR) and a mass spectrum (MS).

Representative examples of the compound of the general formula (I) thus obtained are shown in Table 1.

[0034]

[Table 1]

(In the table, Cr represents a crystal phase, N ^* represents a chiral nematic phase, and I represents an isotropic liquid phase.
() Indicates that the phase is a monotropic phase. The phase transition temperature indicates a transition temperature between the phase on the left side and the phase on the right side of the figure. For example, Cr91I indicates that the transition temperature between the crystal phase and the isotropic liquid phase is 91 ° C. . )

The compound of the general formula (I) of the present invention can induce a sufficiently large spontaneous polarization by adding a small amount to the SC base liquid crystal, thereby enabling a high-speed response.

As such an example, for example,

[0038]

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The spontaneous polarization at 25 ° C. of the SC ^* liquid crystal composition comprising 98% by weight of a phenylpyrimidine-based parent liquid crystal and only 2% by weight of the compound (No. 1) in Table 1 was +5.5 nC / cm ² , and a high-speed response of 70 μs was confirmed in a display cell manufactured using the same.

On the other hand, among the ester-type optically active compounds of the aforementioned general formula (IV), a representative compound of the formula (R)

[0041]

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The spontaneous polarization at 25 ° C. of the SC ^* liquid crystal composition comprising 2% by weight of the compound and 98% by weight of the same parent liquid crystal was +4.5 nC / cm ² , and the response measured in the same manner was 97 μsec. It has become quite late.

As described above, the compound of the general formula (I) of the present invention is obtained by replacing the ester type skeleton of the conventional compound of the general formula (IV) with a phenylpyrimidine type skeleton. It is clear that the responsiveness is considerably improved.

Further, the compound (No. 1) 10 of the present invention
SC consisting of 90% by weight of the same parent liquid crystal as above.
^{* After} preparing the liquid crystal composition and leaving it at room temperature for a long time,
No precipitation or phase separation was observed.

On the other hand, an SC ^* liquid crystal composition comprising 10% by weight of the compound of the formula (R) and 90% by weight of the same parent liquid crystal was prepared, and left at room temperature.
After a week, precipitation was observed.

Accordingly, it is apparent that the compound of the general formula (I) of the present invention is superior to the conventionally known compound of the general formula (IV) particularly in the compatibility with phenylpyrimidine-based parent liquid crystals. .

As described above, since the compound of the general formula (I) of the present invention can induce a sufficiently large spontaneous polarization even with a small amount of addition, the addition amount to the SC parent liquid crystal may be about 1% by weight. When other chiral dopants are used in combination, a smaller amount is possible, but the total amount of the compound of the general formula (I) is preferably 1% by weight or more.

From the above Table 1, it can be seen that some of the compounds of the general formula (I) of the present invention do not show the SC ^* phase by themselves, but as described above, the addition amount is small, so It rarely narrows the temperature range of the SC ^* phase of the product.

In general, an optically active compound which induces a large spontaneous polarization even when added in a small amount has a tendency that the temperature range of the chiral nematic (N ^* ) phase of the composition is narrowed or easily eliminated. And smectic A (S
A) Many of them have a strong tendency to expand the temperature range of the phase.
When such a compound is added as a chiral dopant, the obtained SC ^* liquid crystal composition has a phase sequence of I (isotropic liquid phase) -SA (smectic A phase)-
Often SC ^* .

However, according to the current alignment technology, it is most desirable that the SC ^* liquid crystal composition exhibits an IN ^* -SA-SC ^* phase sequence from a high temperature range. By adding the compound of the general formula (I) of the present invention to a base liquid crystal,
Obtaining the desired phase series described above is very easy, since there is little tendency to narrow the temperature range of the N ^* phase or widen the temperature range of the SA phase of the composition.

Further, in order to obtain excellent orientation, in addition to the above-described phase sequence of IN ^* -SA-SC ^* , N ^* and S
It is also important that the helical pitch in the C ^* phase, especially in the N ^* phase, is large. In order to increase the helical pitch, it is sufficient to add an optically active compound in which the direction of the induced helical is reversed. However, the compound of the general formula (I) of the present invention requires a small amount of addition. The helical pitch is large for its spontaneous polarization, and adjustment is relatively easy.

Examples of the SC compound used in the base liquid crystal to which the compound of the general formula (I) of the present invention is added as a dopant include, for example, the following general formula (A)

[0053]

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(Wherein R ^a and R ^b represent a linear or branched alkyl group, alkoxyl group, alkoxycarbonyl group, alkanoyloxy group or alkoxycarbonyloxy group, and may be the same or different. A phenylbenzoate compound represented by the general formula (B):

[0055]

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(Wherein R ^a and R ^b have the same meanings as in formula (A)). In addition, general formulas (A) and (B)
General formula (C) including

[0057]

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(Wherein R ^a and R ^b have the same meanings as in formula (A), and ring L and ring M are each 1,4
-Phenylene group, 1,4-cyclohexylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, pyrazine-2,5-diyl group, pyridazine-3,6
- diyl group, 1,3-dioxane-2,5-diyl group, or represents these halogen substituents may be the being the same or different, Z ^a is -COO -, - O
_{CO -, - CH 2 O -} , - OCH 2 -, - CH 2 CH 2 -,
—C≡C— or a single bond. The compound represented by the formula (1) can be used for the same purpose.

In order to extend the temperature range of the SC phase to a high temperature range, the general formula (D)

[0060]

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(Wherein, R ^a and R ^b have the same meanings as in formula (A), and ring L, ring M and ring N have the same meanings as ring L and ring M in formula (C). , represented by one another be the same or different, represent the same meaning as Z ^a, respectively Z ^a and Z ^b in the general formula (C), and may be the same or different from each other.) Tricyclic compounds can be used.

It is effective to mix these compounds and use them as an SC liquid crystal composition. However, it is only necessary that the composition shows an SC phase, and it is not necessary for each compound to show the SC phase. .

By adding the compound of the formula (I) of the present invention and, if necessary, other optically active compounds as chiral dopants to the thus obtained SC liquid crystal composition, a wide temperature range including room temperature can be easily obtained. Thus, a liquid crystal composition exhibiting an SC ^* phase can be obtained.

The compound of the general formula (I) of the present invention is
SC obtained by adding to parent liquid crystal^*Two liquid crystal compositions
Between 1 and 20 μm between transparent glass electrodes
By inserting, it can be used as a display cell. Good
In order to obtain a high contrast, a uniform
Must be implemented, and many methods have been
ing. In order to show good alignment,
From the high temperature side ^*-SA-SC^*Indicates the phase series of
N^*Phase and SC^*Increasing the helical pitch in the phase
Is required, but as described above, the general formula (I) of the present invention
In the case of a composition containing the compound of formula (1), the adjustment is easy.
You.

[0065]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the gist and scope of the present invention are, of course, not limited by these examples.

The structure of the compound is represented by NMR, IR, MS
And elemental analysis. The phase transition temperature was measured using a polarizing microscope equipped with a temperature control stage and a differential scanning calorimeter (DSC). (KBr) in IR
Indicates measurement by tablet molding, and (neat) indicates measurement by liquid film. CDCl _{3 in} NMR represents a solvent, s represents a singlet, d represents a doublet, t represents a triplet, m represents a multiplet, and, for example, dt represents a double triplet. M ^{+ in} MS represents the parent peak, and the number in parentheses represents the relative intensity of that peak. In addition, "%" in a composition all represents "weight%."

(Example 1) (2R, 4R) -2- (4
-Bromophenyl) -4-decanolide (general formula (II)
1.7 ml (12.0 mmol) of diisopropylamine
In a solution of 10 ml of tetrahydrofuran (THF).
7.3 ml of 6M butyl lithium-hexane solution (12.
(0 mmol) at -78 ° C and stirred for 30 minutes. This was mixed with 2 ml of hexamethylphosphoric acid triamide and 1.1 g (5.0 mmol) of 4-bromophenylacetic acid in 10 m of THF.
Then, the mixture was stirred at -78 ° C for 30 minutes. Further (R)
15 ml of a THF solution containing 1.28 g (10.0 mmol) of -1,2-epoxyoctane was added, and the mixture was stirred at -30 ° C overnight. After completion of the reaction, 3M hydrochloric acid was added to the reaction solution to adjust the pH to 1
The reaction product was extracted three times with 50 ml of dichloromethane. After concentrating the organic layer, 20 ml of toluene was added to the residue,
10 mg of p-toluenesulfonic acid was added, and the mixture was heated under reflux for 3 hours. After concentrating the reaction solution, it was separated and purified using silica gel column chromatography (hexane / ethyl acetate = 20/1) to obtain polar components (2R, 4R) -2- (4
455 mg (28% yield) of -bromophenyl) -4-decanolide and 306 mg of non-polar component (2S, 4R) -2- (4-bromophenyl) -4-decanolide (19 yield)
%).

Polar component: (2R, 4R) -2- (4-bromophenyl) -4-decanolide Colorless plate crystal Melting point 88.7 ° C. [α] _D + 10.3 ° (c = 1.30, CHCl ₃ , 2
0 ° C) IR (neat) 2950,2920,2850,1
760, 1750, 1490, 1070, 1010, 9
_{^{30,825cm -1 1 H NMR (CDCl 3}} ) δ 0.90 (t, J =
6.8 Hz, 3H), 1.25 to 1.54 (m, 8
H), 1.64-1.72 (m, 1H), 1.79-
1.88 (m, 1H), 1.99 (td, J =, 12.
7 and 10.5 Hz, 1 H), 2.74 (ddd, J
= 12.7, 8.6, and 5.3 Hz, 1H), 3.
83 (dd, J = 12.7 and 8.6 Hz, 1H),
4.48 (ddt, J = 10.5, 7.4, and 5.
3 Hz, 1 H), 7.17 (d, J = 8.4 Hz, 2
H), 7.49 (d, J = 8.4 Hz, 2H) MS m / z 326 (M ^{++ 2,} 3), 324 (M ⁺ ,
3), 282 (12), 280 (12), 197 (1
7), 195 (12), 185 (12), 184 (9
8), 183 (14), 182 (100), 129 (1
3) Elemental analysis: C ₁₆ H ₂₁ O ₂ Br Calculated: C, 59.09%; H, 6.51%; Br, 2
4.57% Found: C, 58.82%; H, 6.35%; Br, 2
4.39%

Example 2 (2R, 4R) -2- [4
-(5-octylpyrimidin-2-yl) phenyl]-
Synthesis of 4-decanolide (Compound No. 1) Dibromobis (triphenylphosphine) nickel (I
I) 174 mg (0.23 mmol), zinc 78 mg
(1.2 mmol), tetramethylammonium bromide 2
(2R, 4R) -2- (4-bromophenyl)-obtained in the above (Example 1) to 00 mg (1.3 mmol).
A solution of 127 mg (0.4 mmol) of 4-decanolide and 89 mg (0.4 mmol) of 2-chloro-5-octylpyrimidine in 1 ml of THF was added, and the mixture was stirred at 50 ° C for 2 hours. After 2 ml of 3M hydrochloric acid was added, the mixture was further neutralized with saturated sodium bicarbonate, filtered through celite, and the reaction product was extracted with 50 ml of ethyl acetate. After concentrating the organic layer, the residue was separated and purified using silica gel column chromatography (hexane / ethyl acetate = 20/1) to give (2R, 4
31 mg of R) -2- [4- (5-octylpyrimidin-2-yl) phenyl] -4-decanolide (yield 18
%).

Colorless plate crystal Melting point 91 ° C. [α] _D + 5.6 ° (c = 0.70, CHCl ₃ , 20
° C) IR (neat) 2930,2860,1755,1
_{^{540,1430,1185cm -1 1 H NMR (CDCl 3}} ) δ 0.88 (t, J =
7.1 Hz, 3H), 0.90 (t, J = 6.9 Hz,
3H), 1.25-1.55 (m, 18H), 1.61.
-1.75 (m, 3H), 1.82-1.92 (m, 1
H), 2.09 (td, J = 12.7 and 10.6H)
z, 1H), 2.62 (t, J = 7.6 Hz, 2H),
2.79 (ddd, J = 12.7, 8.7, and5.
4 Hz, 1 H), 3.95 (dd, J = 12.7 and)
8.7 Hz, 1 H), 4.52 (ddt, J = 10.
6, 7.3, and 5.4 Hz, 1 H), 7.41
(D, J = 8.4 Hz, 2H), 8.41 (d, J =
8.4 Hz, 2H), 8.62 (s, 2H) MS m / z 436 (M ⁺ , 28), 393 (2
0), 392 (65), 321 (15), 307 (10
0), 296 (14), 295 (46), 294 (2
9), 282 (19), 281 (11) Elemental analysis C ₂₈ H ₄₀ N ₂ O ₂ Calculated: C, 77.02%; H, 9.23%; N, 6.
42% Found: C, 76.72%; H, 9.19%; N, 6.
38%

Example 3 (2R, 4R) -2- [4
-[5- (4-heptylphenyl) pyrimidin-2-yl] phenyl] -4-decanolide (compound of No. 2)
In the same manner as in Example 2, 2-chloro-5- (4-hexylphenyl) pyrimidine 110 mg (0.4 mmol), (2R, 4R) -2- (4-bromophenyl)-
From 127 mg (0.4 mmol) of 4-decanolide,
47 mg of (2R, 4R) -2- [4- [5- (heptylphenyl) pyrimidin-2-yl] phenyl] -4-decanolide was obtained (yield 25%). Colorless powder Phase transition temperature (° C) Cr158.7 (N ^* 158.4)
I [α] _D + 5.6 ° (c = 0.70, CHCl ₃ , 20
° C) IR (neat) 2950,2925,2850,1
_{^{770,1440,1175,930,825cm -1 1 H NMR (CDCl 3}} ) δ 0.899 (t, J =
7.0 Hz, 3H), 0.903 (t, J = 7.0 H)
z, 3H), 1.28-1.57 (m, 14H), 1.
62-1.76 (m, 3H), 1.83-1.92
(M, 1H), 2.10 (td, J = 12.7 and 1
0.5 Hz, 1 H), 2.68 (t, J = 7.6 Hz,
2H), 2.81 (ddd, J = 12.7, 8.7, a
nd 5.4 Hz, 1H), 3.97 (dd.J = 12.
7 and 8.7 Hz, 1H), 4.52 (ddt, J =
10.5, 7.3, and 5.4 Hz, 1H), 7.3
4 (d, J = 8.2 Hz, 2H), 7.44 (d, J =
8.4 Hz, 2H), 7.55 (d, J = 8.2 Hz,
2H), 8.49 (d, J = 8.4 Hz, 2H), 9.
00 (s, 2H) MS m / z 484 (M ⁺ , 6), 441 (11),
440 (100), 369 (20), 354 (10
0), 343 (44), 342 (15), 285 (1
1), 284 (30), 273 (20), 271 (6
4) Elemental analysis C ₃₂ H ₄₀ N ₂ O ₂ Calculated: C, 79.30%; H, 8.32%; N, 5.
78% found: C, 70.04%; H, 8.36%; N, 5.
69%

Example 4 Preparation of SC ^* Liquid Crystal Composition An SC parent liquid crystal (H-1) having the following composition was prepared.

[0073]

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The phase transition temperature of the base liquid crystal was as follows. Phase transition temperature (° C) Cr12.5 SC55.5 SA
64.5 N70 I 98% of this SC base liquid crystal (H-1) and N of Example 2
o. SC ^* liquid crystal composition (M-
1) was prepared. The phase transition temperature was as follows.

Phase transition temperature (° C.) SC ^* 56 SA62
N ^* 67I The melting point was not clear.

In the same manner, SC matrix liquid crystal (H-1) 96
% And 4% of the compound of (No. 1) to prepare an SC ^* liquid crystal composition (M-2). The phase transition temperature was as follows.

Phase transition temperature (° C.) SC ^* 57.5 SA
From 60 N ^* 67I or more, even if the addition amount of the compound of (No. 1) is increased, the temperature range of the composition, particularly the temperature range of the SC ^* phase is hardly changed, but rather expanded. It is clear that.

Next, 98% of SC base liquid crystal (H-1) and No. 3 of Example 3 were used. SC ^* liquid crystal composition (M-3) consisting of 2% of compound 2 was prepared. The phase transition temperature was as follows.

Phase transition temperature (° C.) SC ^* 57.5 SA
Similarly, (H-1) 97% and No. 64N ^* 69.5I were obtained. Compound 3 of 2
% Of SC ^* liquid crystal composition (M-4). The phase transition temperature was as follows.

Phase transition temperature (° C.) SC ^* 58.5 S
A64.5 N ^* 70.5 I

Example 5 Preparation of Liquid Crystal Display Element The SC ^* liquid crystal composition (M-1) obtained in Example 4 was heated to an isotropic liquid (I) phase, and this was heated to a thickness of 2 μm. A glass cell composed of two transparent electrode plates (polyimide coating-aligned by rubbing) was filled to prepare a display element. When this was gradually cooled to room temperature, a cell of SC ^* phase which was uniformly oriented was obtained. When a rectangular wave with an electric field strength of 10 V _pp / μm and 50 Hz was applied to this cell, and its electro-optical response speed was measured,
A high-speed response of 70 μsec at 25 ° C. was confirmed. At this time, the tilt angle was 25.6 °, and the contrast was very good. This spontaneous polarization is +5.5 nC / cm
^{Was 2} .

Similarly, SC ^* liquid crystal composition (M-2)
To (M-4), a liquid crystal display element was produced, and its characteristics were measured. The results are shown below. (M-2): response 30 μs, spontaneous polarization +15.4 nC / cm
² , tilt angle: 27.2 °, good contrast (M-3): response 90 μs, spontaneous polarization +3.9 nC / c
m ² , tilt angle 22.8 °, good contrast (M-4): response 55 μs, spontaneous polarization +7.6 nC / c
m ² , tilt angle 26.1 °, good contrast

(Comparative Example) SC Base Liquid Crystal (H-1) 98%
And an ester-based formula (R) having an optically active lactone ring.

[0084]

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An SC ^* liquid crystal composition (N-1) consisting of 2% of the compound was prepared. The phase transition temperature was as follows. Phase transition temperature (° C.) SC ^* 56 SA62 N ^* 68.5
I. A cell was prepared in the same manner, and the electro-optical characteristics were measured. The response was 97 μs, which was slower than (M−1). The spontaneous polarization was +4.5 nC / cm ² and the tilt angle was 25.4 °.

Further, an SC ^* liquid crystal composition (N-) comprising 96% of an SC matrix liquid crystal (H-1) and 4% of a compound of the formula (R) was prepared.
2) was prepared. The phase transition temperature was as follows. Phase transition temperature (° C) SC ^* 56 SA60 N ^* 68
I. A cell was fabricated in the same manner, and the electro-optical characteristics were measured. The response was 39 μs, which was slower than (M-2). The spontaneous polarization was +12.7 nC / cm ² and the tilt angle was 23.6 °.

[0087]

The compound of the general formula (I) of the present invention is excellent in compatibility with other liquid crystal compounds, can induce a large spontaneous polarization by adding a small amount as a chiral dopant, and has a wide temperature range. Thus, a liquid crystal composition capable of high-speed response and having excellent alignment properties can be obtained.

The compound of the general formula (I) of the present invention is
It is very practical because it can be easily produced industrially, is colorless and has excellent chemical stability against water, light and the like. Furthermore, in the chiral smectic liquid crystal composition of the present invention, 50 μm
It is possible to realize a high-speed response of sub-second or less, and it is extremely useful as a constituent material of an optical switching element for display.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuo Kusumoto 1-9-2-102 Minamidai, Sagamihara City, Kanagawa Prefecture (72) Inventor Kenichi Sato 35-11 Kamimizo, Sagamihara City, Kanagawa Prefecture (72) Inventor Akiko Nakayama Tokyo 1380-K-702, Yamazaki-cho, Machida-shi (72) Inventor Huang Tori 10525-83, 26th Edmonton, Alberta, Canada (58) Field surveyed (Int. Cl. ⁷ , DB name) C07D 405/10 C07D 307/33 C09K 19/34 CA (STN) REGISTRY (STN)

Claims (7)

(57) [Claims] 1. A compound of the general formula (I) (In the formula, R ¹ represents 1 carbon atom which may be substituted by a fluorine atom or an alkoxyl group having 1 to 10 carbon atoms.)
X represents a single bond or -O-, m represents 0 or 1, and ring A is a 1,4-phenylene group or trans-1, which may be substituted by a fluorine atom. Represents a 4-cyclohexylene group, R ² represents an alkyl group having 1 to 10 carbon atoms, and the asymmetric carbon atoms at the 2- and 4-positions of the lactone ring are each independently (R) or (S) configuration It is. An optically active compound represented by the formula: 2. The optically active compound according to claim 1, wherein m = 0. 3. The optically active compound according to claim 1, wherein m = 1 and Ring A is a 1,4-phenylene group. 4. A liquid crystal composition comprising the optically active compound represented by the general formula (I) according to claim 1. 5. The liquid crystal composition according to claim 4, which exhibits a ferroelectric chiral smectic phase. 6. A compound of the general formula (II) (Wherein, Y represents a halogen atom, R ² represents an alkyl group having 1 to 10 carbon atoms, and the asymmetric carbon atoms at the 2- and 4-positions of the lactone ring are each independently (R) or ( S)
Arrangement. An optically active compound represented by the formula: 7. An optically active compound represented by the general formula (II) according to claim 6, and a compound represented by the general formula (III): (In the formula, R ¹ represents 1 carbon atom which may be substituted by a fluorine atom or an alkoxyl group having 1 to 10 carbon atoms.)
X represents a single bond or -O-, m represents 0 or 1, and ring A is a 1,4-phenylene group or trans-1, which may be substituted by a fluorine atom. Represents a 4-cyclohexylene group, and Z represents a halogen atom. The method for producing a compound represented by the general formula (I) according to claim 1, wherein the compound represented by the formula (I) is reacted.