JPH0578272A - Optically active difluorocyclopropane derivative, liquid crystal composition and liquid crystal display element containing the same - Google Patents

Abstract

PURPOSE:To obtain a new compound useful as a material for ferroelectric liquid crystal displays excellent in high-speed responsiveness and memory properties. CONSTITUTION:A compound, e.g. trans-1,1-difluoro-2-hexyloxymethyl-3-[4(4- octyloxyphenyl)phenyl] cyclopropane expressed by formula I (R<1> is 1-18C alkyl; X is single bond or O; rings A and B are substitutable 1,4-phenylene, trans-1,4- cyclohexylene, pyridine-2,5-diyl, etc.;(m)j)is 0 or 1; R<2> is F, 1-18C alkyl, etc.). The compound expressed by formula I is obtained by reducing an optically active difluorocyclopropanecarboxylic acid ester derivative expressed by formula II (R<3> is optically active alkyl or aralkyl) with a diisobutylaluminum hydride, etc., and further reacting the resultant compound with an alkyl halide expressed by the formula R<2>Y (Y is halogen) in the presence of a base.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel optically active difluorocyclopropane derivative and a liquid crystal material containing the same, and more specifically to a ferroelectric liquid crystal display material excellent in high-speed response and memory property. .

[0002]

2. Description of the Related Art Liquid crystal display devices are widely used at present due to their excellent features (low voltage operation, low power consumption, thin display, can be used even in bright places and do not cause eye strain). However, the most common display method among them, the twisted nematic (TN) type, has an extremely slow response as compared with other light emitting type display methods such as CRT, and also stores the display when the applied electric field is cut off. Since (memory effect) cannot be obtained, there are many restrictions on application to moving screens such as optical shutters that require high-speed response, printer heads, or televisions that require time-division driving, and it is not always a suitable display method. I couldn't say.

Recently, a display method using a ferroelectric liquid crystal has been reported. According to this method, a TN-type liquid crystal display is used.
High-speed response of 0 to 1000 times and memory effect can be obtained, so it is expected as a next-generation liquid crystal display element, and
R & D is actively underway.

The liquid crystal phase of the ferroelectric liquid crystal belongs to the tilt type chiral smectic phase, of which the chiral smectic C (hereinafter abbreviated as Sc ^* ) phase has the lowest viscosity and is most desirable. A large number of liquid crystal compounds exhibiting the Sc ^* phase (hereinafter abbreviated as Sc ^* compounds) have already been synthesized and studied, but in order to use as a ferroelectric liquid crystal display device, the following conditions must be satisfied. is there. That is, (a) Sc ^{* in a} wide temperature range including room temperature
Phase (B) Sc ^* to obtain good orientation
Having an appropriate phase series on the high temperature side of the phase and having a large spiral pitch, and (c) having an appropriate tilt angle,
It is necessary to meet the following conditions: (d) low viscosity, (e) large spontaneous polarization, and (f) high-speed response. However, compounds that satisfy these conditions alone are known. Not not. Therefore, it is necessary to mix several or more kinds of compounds and use them as a liquid crystal composition showing a Sc ^* phase (hereinafter, abbreviated as Sc ^* liquid crystal composition).

The method for preparing the Sc ^* liquid crystal composition is to use a smectic C (hereinafter referred to as Sc
Is omitted. ) A method of adding a chiral dopant composed of an optically active compound to a matrix liquid crystal exhibiting a phase is common. According to this method, a Sc ^* liquid crystal composition having a lower viscosity can be obtained, and a high-speed response becomes possible. The compound used as the chiral dopant is not necessarily Sc ^{* by} itself ^.
It is not necessary to show a phase, or even a liquid crystal phase, but it is possible to induce a sufficient spontaneous polarization in the liquid crystal composition with a small amount of addition, and a sufficiently large helical pitch to be induced as a chiral dopant. It is necessary to show.

In order to induce a large spontaneous polarization in a liquid crystal composition as a chiral dopant, a group having a strong dipole moment must be fixed as close as possible to the central skeleton (core) and asymmetric carbon of the compound molecule. Is already known to be necessary. On the basis of such an idea, the present inventors have made general formula (II)

[0007]

[Chemical 2]

(In the formula, Mes represents a liquid crystal skeleton, and R represents an alkyl group.) An optically active cyanocyclopropane derivative represented by the formula is synthesized, and a sufficiently large spontaneous amount is spontaneously added to the liquid crystal composition by adding a small amount of this compound. It has been found that a Sc ^* liquid crystal composition having a fast response can be obtained by inducing polarization. (Described in page 16 of the 16th Liquid Crystal Conference, and Japanese Patent Application No. 1-331270).
It has been found that the compound having a group having a strong dipole moment fixed to the optically active cyclopropane ring exhibits excellent performance as a chiral dopant.

[0009]

In the compound represented by the general formula (II), a cyano group is used as a group having a strong dipole moment. Conventionally, a liquid crystal compound having a cyano group has been usually used for the purpose of increasing the absolute value of the dielectric anisotropy of a liquid crystal composition such as a nematic liquid crystal, but generally has a drawback that its viscosity is considerably high. Was there. The viscosity of the compound represented by the general formula (II) was not so low.

It is known that the response time (τ) of a ferroelectric liquid crystal is proportional to its viscosity and inversely proportional to its spontaneous polarization.
Therefore, in order to shorten the response time, it is sufficient to lower the viscosity of the liquid crystal composition and increase the spontaneous polarization. However, if the spontaneous polarization is excessively increased, not only the memory property of the liquid crystal display element is adversely affected, but also the viscosity of the liquid crystal composition is increased, so that it cannot actually be increased to a certain degree or more. . Therefore, in order to obtain high-speed response, it is necessary to reduce the viscosity of the liquid crystal composition.

Besides the cyano group, a carbonyl group and a halogen atom such as a fluorine or chlorine atom are known as a group having a large dipole moment. Among these groups, the fluorine atom has not become so high in viscosity that it is becoming more frequently used. Therefore, a compound in which a fluorine atom is directly bonded to an optically active cyclopropane ring is considered to be very preferable as a chiral dopant, but such a liquid crystal compound has not been known so far.

The problem to be solved by the present invention is to add a small amount as a chiral dopant to a host liquid crystal,
We provide an optically active compound that induces a large spontaneous polarization and enables a high-speed response, and a ferroelectric liquid crystal display material that contains this optically active compound and has a large spontaneous polarization and a high-speed response. To provide.

[0013]

In order to solve the above-mentioned problems, the present invention has the general formula (I)

[0014]

[Chemical 3]

(In the formula, R ¹ represents an alkyl group having 1 to 18 carbon atoms, preferably a linear alkyl group having 2 to 12 carbon atoms. X represents a single bond or --O--. Preferably represents -O-. Ring A and ring B are each independently 1,4-phenylene group optionally substituted by 1 or 2 fluorine atoms, trans-1,
4-cyclohexylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, pyrazine-2,5
-Diyl group, pyridazine-3,6-diyl group or 1,3
-Dioxane-2,5-diyl group is represented, preferably 1,4-phenylene group is represented. m represents 0 or 1, but preferably represents 0. R ² represents an alkyl group having 1 to 18 carbon atoms which may be substituted with a fluorine atom or an alkoxyl group having 1 to 10 carbon atoms, preferably a linear alkyl group having 1 to 10 carbon atoms. Represents The asymmetric carbon atoms at the 2- and 3-positions of the cyclopropane ring are each independently in the (R) or (S) configuration. )
An optically active difluorocyclopropane derivative represented by

The present invention also provides a liquid crystal composition containing the optically active difluorocyclopropane derivative represented by the above general formula (I).

The liquid crystal composition of the present invention contains at least one kind of the compound represented by the general formula (I) as a constituent component. Particularly, as a ferroelectric liquid crystal display material, the main component Sc is used. A Sc ^* liquid crystal composition containing at least one compound represented by formula (I) in a matrix liquid crystal exhibiting a phase (hereinafter abbreviated as Sc matrix liquid crystal) as a part or all of a chiral dopant is suitable. ing. Further, by adding a small amount of the compound represented by the general formula (I) of the present invention to a nematic liquid crystal, it is possible to prevent a reverse domain of a TN type liquid crystal, or use as a super twisted nematic (STN) type liquid crystal. Available for

The compound represented by the general formula (I) according to the present invention can be produced, for example, according to the following production method.

First, the general formula (III)

[0020]

[Chemical 4]

(Wherein R ¹ , X, ring A, ring B and m are
It has the same meaning as in formula (I) and Z represents a bromine or iodine atom. ) Is reacted with 2-propyn-1-ol in the presence of a catalyst to give a compound represented by the general formula (IV):

[0022]

[Chemical 5]

(Wherein R ¹ , X, ring A, ring B and m are
It has the same meaning as in the general formula (I). ) To obtain a 2-propyn-1-ol derivative.

This is reduced with lithium aluminum hydride and then acetylated with acetic anhydride or the like to give a compound of the general formula (V)

[0025]

[Chemical 6]

(Wherein R ¹ , X, ring A, ring B and m are
It has the same meaning as in the general formula (I). ) To obtain a trans-2-propen-1-ol ester derivative.

This is reacted with sodium chlorodifluoroacetate to give a compound of the general formula (VI)

[0028]

[Chemical 7]

(Wherein R ¹ , X, ring A, ring B and m are
It has the same meaning as in the general formula (I). ) To obtain a difluorocyclopropane derivative.

Further, this is hydrolyzed with alkali and then oxidized with potassium permanganate or the like to give a carboxylic acid, and then in the presence of a condensing agent such as dicyclohexylcarbodiimide (DCC), an optically active alcohol R ³ OH (in the formula: , R ³
Represents an optically active alkyl group or aralkyl group. )
A difluorocyclopropanecarboxylic acid ester derivative is obtained by reacting with.

Although this is a mixture of diastereomers,
It can be separated by an ordinary separation method such as chromatography, and has the general formula (VII)

[0032]

[Chemical 8]

(Wherein R ¹ , X, ring A, ring B and m are
It has the same meaning as in formula (I), and R ³ represents an optically active alkyl group or aralkyl group. ) To obtain an optically active difluorocyclopropanecarboxylic acid ester derivative.

This is reduced with diisobutylaluminum hydride or the like, and further in the presence of a base, an alkyl halide R ²
By reacting with Y (in the formula, Y represents a halogen atom of bromine, chlorine or iodine, and R ² has the same meaning as in the general formula (I)); An active difluorocyclopropane derivative can be obtained.

The compound represented by the general formula (III) used as a raw material is generally used as a raw material for synthesizing a liquid crystal compound, some of which are commercially available and some of which are not commercially available. It can be easily obtained by a usual synthetic chemical method.

As described above, the general formula (I) of the present invention is used.
The compounds represented by can be obtained, and the individual specific compounds belonging to these compounds have a phase transition temperature such as a melting point,
It can be confirmed by means of infrared absorption spectrum (IR), nuclear magnetic resonance spectrum (NMR), mass spectrum (MS), elemental analysis and the like.

Table 1 shows typical examples of the compounds represented by the general formula (I) thus obtained.

[0038]

[Table 1]

One of the excellent features of the compound represented by the general formula (I) is that a liquid crystal capable of inducing a sufficiently large spontaneous polarization even when added in a small amount when added to a liquid crystal composition and capable of high-speed response. It can be mentioned that the composition can be obtained. For example, No. 1 in Table 1 obtained in Example 1 described later. Only 5% by weight of the compound shown in 1
The value of spontaneous polarization at 25 ° C. of the Sc ^* liquid crystal composition containing 95% by weight of the phenylpyrimidine-based host liquid crystal exhibiting a phase is about 3 nC / cm ² . How large the value of this spontaneous polarization is depends on the Sc ^* liquid crystal compound derived from (S) -2-methylbutanol, which is most commonly used as a chiral source in liquid crystals, such as 4-decyloxybenzoic acid 4-[(S).
It is clear that the spontaneous polarization of -2-methylbutoxy] phenyl is about 1 to ² nC / cm ² alone without adding to the host liquid crystal. Also this Sc
^{* The} liquid crystal composition shows a high-speed response of about 100 μsec at room temperature, but it is understood that this compound has a considerably low viscosity in view of the magnitude of spontaneous polarization.

Many of the compounds represented by the general formula (I) do not exhibit a liquid crystal phase by themselves, but since the addition amount to the host liquid crystal may be small, the liquid crystal phase of the liquid crystal composition, particularly Sc ^*.
It does not narrow the temperature range of the phases.

Examples of the compound showing the Sc phase (hereinafter abbreviated as Sc compound) used in the host liquid crystal to which the compound represented by the general formula (I) of the present invention is added as a chiral dopant include, for example, the following general formula ( A)

[0042]

[Chemical 9]

(In the formula, R ^a and R ^b represent an alkyl group, an alkoxyl group, an alkoxycarbonyl group, an alkanoyloxy group or an alkoxycarbonyloxy group, which may be the same or different from each other). Phenylbenzoate compounds represented by the general formula (B)

[0044]

[Chemical 10]

A phenylpyrimidine compound represented by the formula (wherein R ^a and R ^b have the same meaning as in the case of the general formula (A)) can be given.

The general formula (C) including the general formulas (A) and (B) is also included.

[0047]

[Chemical 11]

(In the formula, R ^a and R ^b have the same meanings as in the general formula (A), and the ring L and the ring M are 1,4-phenylene group, 1,4-cyclohexylene group, and
Pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, pyrazine-2,5-diyl group, pyridazine-
It represents a 3,6-diyl group, a 1,3-dioxane-2,5-diyl group or a halogen-substituted product thereof, which may be the same or different from each other, and Z ^{a is-.}
COO -, - OCO -, - CH 2 O -, - OCH 2 -, -
CH ₂ CH ₂ —, —C≡C— or a single bond. The compound represented by () can be used for the same purpose.

For the purpose of expanding the temperature range of the Sc phase of the liquid crystal composition to a high temperature range, the general formula (D)

[0050]

[Chemical 12]

(In the formula, R ^a and R ^b have the same meanings as in the general formula (A), and the ring L, the ring M and the ring N have the same meanings as the ring L and the ring M in the general formula (C). Which may be the same or different from each other, Z ^a and Z ^b each have the same meaning as Z ^a in the general formula (C), and these may be the same or different from each other. It is possible to use a tricyclic compound represented by

It is effective to use these compounds as a matrix liquid crystal of Sc by mixing these compounds, but it is only necessary to show the Sc phase as a composition, and it is not always necessary for each compound to show the Sc phase. .

To the thus obtained Sc matrix liquid crystal, the compound represented by the general formula (I) of the present invention and, if necessary, other optically active compound are added as a chiral dopant, so that the room temperature can be easily increased. Sc in a wide temperature range including
^* A liquid crystal composition exhibiting a phase can be obtained.

Further, the Sc ^* liquid crystal composition obtained by adding the compound represented by the general formula (I) of the present invention to the Sc matrix liquid crystal is a thin film of about 1 to 20 μm between two transparent glass electrodes. By encapsulating as, it can be used as a display cell. In order to obtain good contrast, it is necessary to make the monodomain uniformly oriented. For this reason, many methods have been tried, but in order to exhibit a good alignment property, the liquid crystal material is I (isotropic liquid) phase-N from the high temperature side.
^* (Chiral nematic) phase-S _A (smectic A) phase-
Sc ^* phase or shows a phase sequence I-phase -S _A phase -Sc ^* phase, N ^*
It is said that it is necessary to increase the spiral pitch in the phase and Sc ^* phase. In order to increase the spiral pitch, a method of mixing an appropriate amount of chiral compounds having mutually opposite twist directions is generally used, but in the compound represented by the general formula (I) of the present invention, the induced spiral pitch is considerably large. In addition to being large, the addition amount required for high-speed response is small, so that the spiral pitch adjustment is almost unnecessary.

[0055]

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

The structure of each compound was confirmed by NMR, IR, MS and elemental analysis. The phase transition temperature is measured by a polarization microscope equipped with a temperature control stage and a differential scanning calorimeter (DS).
It carried out using C) together. (KBr) in IR represents the measurement by tableting. CDCl _{3 in} NMR represents a solvent, s is a singlet, d is a doublet, t is a triplet,
q represents a quartet, quintet represents a quintet, sextet represents a 6t, m represents a multiplet, and b represents a broad absorption. Further, for example, dt represents a double triplet line. J represents a coupling constant. M ^{+ in} MS represents the parent peak, and the value in parentheses represents the relative intensity of that peak. All "%" in the composition represent "% by weight".

Example 1 trans-1,1-difluoro-2-hexyloxymethyl-3- [4- (4-octyloxyphenyl) phenyl] cyclopropane (Table 1 represented by the general formula (I)) No. 1 and No.
Compound 2)

(1-a) 3- [4- (4-octyloxyphenyl) phenyl]
Synthesis of 2-propyn-1-ol

[0059]

[Chemical 13]

4-Bromo-4'-octyloxybiphenyl 15 g (42 mmol) triethylamine 100
In a ml solution, 4.8 ml of 2-propyn-1-ol (8
3 mmol) and 1.5 g (2.1 mmol) of dichlorobis (triphenylphosphine) palladium (II).
0.2 g (1.0 mmol) of copper (I) iodide was added,
The mixture was heated under reflux for 7 hours. After completion of the reaction, ethyl ether 50
0 ml was added and the mixture was filtered through Celite. The filtrate was poured into 1000 ml of saturated saline, the organic layer was separated, and the reaction product was extracted from this organic layer three times with 100 ml of ethyl ether. 200 ml of 1M hydrochloric acid aqueous solution and 200 m of saturated sodium hydrogen carbonate aqueous solution
1 and further washed with 200 ml of saturated saline and dried over anhydrous sodium sulfate. After filtering this, the filtrate was concentrated under reduced pressure, and the obtained residue was separated and purified using column chromatography (filler: Wakogel C-200, developing solvent: hexane / ethyl acetate = 5/1), and 3 -[4-
7.7 g (yield 55%) of (4-octyloxyphenyl) phenyl] -2-propyn-1-ol was obtained.

Melting point: 140 to 142 ° C.

IR (KBr) 3100-3600,2
950, 2875, 1610, 1500, 1480, 1
290,1252,1038,830cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.88
(T, J = 7.0 Hz, 3 H), 1.1 to 2.0 (m,
12H), 1.60 (s, 1H), 3.97 (t, J =
7.0Hz, 2H), 4.48 (d, J = 5.0Hz,
2H), 6.93 (d, J = 9.0Hz, 2H), 7.
48 (m, 4H), 7.49 (d, J = 9.0Hz, 2
H)

MS m / z 336 (M ⁺ , 10
0), 224 (83)

[0065] Elemental analysis: C ₂₃ H ₂₈ O ₂ Calculated: C, 82.10%; H, 8.38% Found: C, 82.07%; H, 8.51%

(1-b) Synthesis of (E) -1-acetoxy-3- [4- (4-octyloxyphenyl) phenyl] -2-propene

[0067]

[Chemical 14]

Compound 3.4 obtained in Example (1-a)
g (10 mmol) in 150 ml of ethyl ether at room temperature, 0.87 g of lithium aluminum hydride (2
A suspension of 3 mmol of ethyl ether in 50 ml was added dropwise, and the mixture was stirred for 1 hour. After completion of the reaction, add 0.5 to the reaction solution.
After pouring into 400 ml of M hydrochloric acid and further adding 200 ml of tetrahydrofuran (THF), this was filtered, and the reaction product was extracted from the filtrate three times with 200 ml of THF. 100 ml of this saturated aqueous sodium hydrogen carbonate solution,
Then, it was washed with 100 ml of saturated saline solution, dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain (E) -3- [4- (4-octyloxyphenyl) phenyl] -2-propene. 3.3 g of -1-ol crude product was obtained. A solution of this crude product in 50 ml of THF was added with 9.4 ml (100 mmol) of acetic anhydride and 8 ml (10 ml) of pyridine.
(0 mmol) was added and the mixture was stirred at room temperature for 5 hours. After the reaction was completed, the reaction solution was added with a saturated sodium hydrogen carbonate aqueous solution
The reaction product was extracted 3 times with 100 ml of ether, and the extract was washed with 100 ml of saturated saline. The solution was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure. The obtained residue is separated and purified using column chromatography (filler: Wakogel C-200, developing solvent: hexane / ethyl acetate = 5/1) to obtain (E) -1-acetoxy-3- [4- (4-octyloxyphenyl) phenyl] -2-propene 2.8
g (yield 81%) was obtained.

Melting point: 131 to 133 ° C.

IR (KBr) 2950,2880,1
745 (CO), 1610, 1505, 1295, 12
60,972,835,785cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 7.0 Hz, 3H), 1.26 to 1.40
(M, 8H), 1.47 (quintet, J = 7.0)
Hz, 2H), 1.80 (quintet, J = 6.5)
Hz, 2H), 2.11 (s, 3H), 3.99 (t,
J = 6.5 Hz, 2H), 4.74 (dd, J = 6.4)
and1.2 Hz, 2H), 6.30 (dt, J = 1)
5.9 and 6.4 Hz, 1H), 6.67 (d, J =
15.9 Hz, 1H), 6.96 (d, J = 8.8H)
z, 2H), 7.43 (d, J = 8.3Hz, 2H),
7.51 (d, J = 8.8Hz, 4H)

MS m / z 380 (M ⁺ , 100),
226 (30), 43 (53)

Elemental analysis: Calculated as C ₂₅ H ₃₂ O ₃ : C, 78.91%; H, 8.47% Actual value: C, 78.77%; H, 8.52%

(1-c) Synthesis of trans-2-acetoxymethyl-1,1-difluoro-3- [4- (4-octyloxyphenyl) phenyl] cyclopropane

[0075]

[Chemical 15]

Compound 2.6 obtained in Example (1-b)
A solution of 4 g (6.9 mmol) of diethylene glycol dimethyl ether in 30 ml was heated under reflux, and to this reaction solution was added sodium chlorodifluoroacetate 5.3 g (35 mmol) of diethylene glycol dimethyl ether in 30 ml.
The solution was added dropwise over 0.5 hour. After heating under reflux for another 10 minutes, the mixture was cooled to room temperature, and the reaction mixture was mixed with ice water.
After pouring into 0 ml and then adding 100 ml of hexane, the mixture was filtered through Celite. After separating the organic layer of this filtrate, the reaction product was extracted twice with 50 ml of ether from this organic layer, and the extract was saturated with saturated saline solution.
It was washed 3 times with ml and dried over anhydrous sodium sulfate. After filtering this and concentrating the filtrate under reduced pressure, the obtained residue was subjected to column chromatography (filler: Kieselgel).
60, developing solvent: hexane / ethyl acetate = 10/1) for separation and purification, and trans-2-acetoxymethyl-1,1-difluoro-3- [4- (4-octyloxyphenyl) phenyl] cyclo. 2.8 g (yield 92%) of propane was obtained.

Melting point: 44 to 45 ° C.

IR (KBr) 2940,2860,1
743 (CO), 1610, 1503, 1475, 13
70, 1210 to 1300, 1180, 1050, 10
30,1020,820cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.8
9 (t, J = 7.0 Hz, 3H), 1.24 to 1.41
(M, 8H), 1.47 (quintet, J = 7.1)
Hz, 2H), 1.80 (quintet, J = 6.6)
Hz, 2H), 2.11 (s, 3H), 2.28 (d
q, J = 14 and 7.6 Hz, 1H), 2.68 (d
d, J = 14 and 7.6 Hz, 1H), 3.99
(T, J = 6.6 Hz, 2H), 4.26 (ddd, J
= 11.9, 7.7, and 1.5Hz, 1H), 4.
37 (ddd, J = 11.9, 7.5, and1.3H
z, 1H), 6.96 (d, J = 8.7Hz, 2H),
7.25 (d, J = 8.2 Hz, 2H), 7.49
(D, J = 8.7 Hz, 2H), 7.51 (d, J =
8.3Hz, 2H)

MS m / z 430 (M ⁺ , 92), 3
80 (26), 258 (86), 256 (63), 23
8 (18), 43 (100)

[0081] Elemental analysis: Calculated _{C 26 H 32 F 2 O 3} : C, 72.53%; H, 7.49% Found: C, 72.68%; H, 7.61%

(1-d) Synthesis of trans-2-hydroxymethyl-1,1-difluoro-3- [4- (4-octyloxyphenyl) phenyl] cyclopropane

[0083]

[Chemical 16]

Compound 2.5 obtained in Example (1-c)
g (5.8 mmol) in THF 50 ml solution, potassium hydroxide 1.0 g (17 mmol) in methanol 20 m
1 solution was added dropwise and the mixture was stirred at room temperature for 1 hour. After the reaction,
The reaction solution was poured into 200 ml of 1M hydrochloric acid, and the reaction product was extracted three times with 100 ml of ether, and the extract was washed with 100 ml of a saturated aqueous sodium hydrogen carbonate solution and then with 100 ml of a saturated saline solution. Further, this extract was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure. The obtained residue is separated and purified using column chromatography (filler: Kieselgel 60, developing solvent: hexane / ethyl acetate = 3/1), and trans-2-hydroxymethyl-1,1-difluoro-
3- [4- (4-octyloxyphenyl) phenyl]
2.1 g (yield 91%) of cyclopropane was obtained.

Melting point: 101 to 102 ° C.

IR (KBr) 3200-3600,2
950, 2870, 1610, 1480, 1270, 1
255,1162,1048,1020,1000,8
26 cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 7.0 Hz, 3 H), 1.2 to 1.4 (m,
8H), 1.47 (quintet, J = 7.1 Hz,
2H), 1.6 (bs, 1H), 1.80 (quint)
et, J = 6.6 Hz, 2H), 2.22 (dqd, J
= 13.0, 7.7, and 1.7 Hz, 1H), 2.
64 (ddd, J = 13.0, 7.5, and 1.7H
z, 1H), 3.84 to 3.92 (m, 1H), 3.9.
3 to 4.00 (m, 1H), 3.99 (t, J = 6.6)
Hz, 2H), 6.95 (d, J = 8.8Hz, 2
H), 7.26 (d, J = 8.2 Hz, 2H), 7.4
8 (d, J = 8.7 Hz, 2H), 7.51 (d, J =
8.1Hz, 2H)

MS m / z 388 (M ⁺ , 99), 2
56 (45), 245 (58), 225 (59), 57
(55), 43 (100)

Elemental analysis: Calculated as C ₂₄ H ₃₀ F ₂ O ₂ : C, 74.20%; H, 7.78% Actual value: C, 74.24%; H, 7.85%

(1-e) Synthesis of trans-2,2-difluoro-3- [4- (4-octyloxyphenyl) phenyl] cyclopropanecarboxylic acid (S) -1-phenylethyl

[0091]

[Chemical 17]

0.12 g (0.4 mmol) of tetrabutylammonium bromide was added to 100 ml of an aqueous solution of 1.2 g (7.7 mmol) of potassium permanganate, which was obtained in Example (1-d). 80 ml of a benzene solution containing 1.0 g (2.6 mmol) of the compound was added, and the mixture was stirred at room temperature for 20 hours. After completion of the reaction, 2.0 g of sodium hydrogen sulfite was added, the mixture was poured into 500 ml of 1M hydrochloric acid, and the reaction product was extracted 4 times with 100 ml of THF. The extract was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to give trans-2,2-difluoro-3-.
1.1 g of crude [4- (4-octyloxyphenyl) phenyl] cyclopropanecarboxylic acid was obtained. Then
To 3 ml of a solution of 480 mg (1.2 mmol) of this crude product in dichloroethane, 2 ml of a solution of 300 mg (1.4 mmol) of dicyclohexylcarbodiimide (DCC) in dichloroethane was added, and 0.35 ml of (S) -1-phenylethanol (2. 8 mmol) and a small amount of 4-
N, N-Dimethylaminopyridine (DMAP) was added and stirred at room temperature for 20 hours. After completion of the reaction, this reaction solution was filtered through Celite, and the filtrate was poured into 150 ml of a saturated aqueous solution of ammonium chloride, and the reaction product was treated with ether 5
Extract 3 times with 0 ml, and extract this solution with 50 ml of saturated saline solution.
Washed with. The extract was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure. The obtained residue is subjected to column chromatography (filler: Kiesel
gel60, developing solvent: hexane / toluene = 10 /
After separation and purification using 1), 130 mg of trans-2,2-difluoro-3- [4- (4-octyloxyphenyl) phenyl] cyclopropanecarboxylic acid (S) -1-phenylethyl was obtained. Yield 21% (non-polar component /
Polar component = 44/56). Further, this was separated and purified using preparative liquid chromatography (filler: Si-60, developing solvent: hexane / ethyl acetate = 20/1) to separate a non-polar component and a polar component.

Non-polar component Melting point: 72 ° C.

[Α] _D + 89.2 ° (c = 0.52,
CHCl ₃ , 20 ° C)

IR (KBr) 2950,2875,1
730 (CO), 1610, 1505, 1462, 12
90, 1240, 1178, 1150, 983 cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 7.0 Hz, 3H), 1.26 to 1.40
(M, 8H), 1.47 (quintet, J = 6.2)
Hz, 2H), 1.62 (d, J = 6.6Hz, 3
H), 1.80 (quintet, J = 6.9 Hz, 2
H), 2.76 (dd, J = 13.0 and 7.9H
z, 1H), 3.49 (ddd, J = 13.0, 7.
6, and 3.2 Hz, 1H), 3.99 (t, J =
6.5 Hz, 2 H), 5.99 (q, J = 6.6 Hz,
1H), 6.95 (d, J = 8.8Hz, 2H), 7.
25 (d, J = 8.1 Hz, 2H), 7.29 to 7.4.
0 (m, 5H), 7.48 (d, J = 8.8Hz, 2
H), 7.51 (d, J = 8.3Hz, 2H)

MS m / z 506 (M ⁺ , 1), 10
5 (100)

High resolution MS (M ⁺ ) Calculated value (m / z) as C ₃₂ H ₃₆ F ₂ O ₃ 506.2630 Measured value (m / z) 506.2603

Polar component Melting point: 83 ° C.

[Α] _D −72.3 ° (c = 0.57,
CHCl ₃ , 20 ° C)

IR (KBr) 2950,2875,1
730 (CO), 1610, 1505, 1462, 12
90, 1240, 1178, 1150, 983 cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 7.0 Hz, 3H), 1.26 to 1.40
(M, 8H), 1.47 (quintet, J = 6.9)
Hz, 2H), 1.60 (d, J = 6.6Hz, 3
H), 1.80 (quintet, J = 6.6 Hz, 2
H), 2.78 (dd, J = 13.0 and 7.9H
z, 1H), 3.51 (ddd, J = 13.0, 7.
6, and 2.7 Hz, 1H), 3.99 (t, J =
6.5 Hz, 2 H), 6.00 (q, J = 6.6 Hz,
1H), 6.96 (d, J = 8.6Hz, 2H), 7.
28 (d, J = 8.2 Hz, 2H), 7.31 to 7.4
0 (m, 5H), 7.49 (d, J = 8.6Hz, 2
H), 7.53 (d, J = 8.3 Hz, 2H)

MS m / z 506 (M ⁺ , 1), 10
5 (100)

Elemental analysis: Calculated as C ₃₂ H ₃₆ F ₂ O ₃ : C, 75.86%; H, 7.16% Actual value: C, 75.82%; H, 7.33%

(1-f) (+)-trans-1,1-difluoro-2-hydroxymethyl-3- [4- (4-octyloxyphenyl)
Synthesis of [phenyl] cyclopropane

[0106]

[Chemical 18] (In the formula, Ph represents a phenyl group.)

Nonpolar component of the compound obtained in Example (1-e) 24 mg (0.047 mmol) of toluene 1 m
diisobutylaluminum hydride (D
0.12 ml of a 1.0 M toluene solution of (IBAL-H) was added dropwise, and the mixture was stirred for 1 hour. After the reaction is complete, add 1 part of this reaction solution.
It is poured into 20 ml of M hydrochloric acid and the reaction product is treated with 10 m of ether
Extract 3 times with 1. The extract was washed with 10 ml of a saturated aqueous sodium hydrogen carbonate solution and then with saturated saline (10 ml), and dried over anhydrous sodium sulfate. This was filtered, the filtrate was concentrated under reduced pressure, and the obtained residue was subjected to thin layer chromatography (developing solvent: hexane / ethyl acetate = 2 /
1) was separated and purified to give white crystals of (+)-trans-1,1-difluoro-2-hydroxymethyl-3-.
16 mg (yield 88%) of [4- (4-octyloxyphenyl) phenyl] cyclopropane was obtained.

Melting point: 120 ° C.

[Α] _D + 20.0 ° (c = 0.44,
CHCl ₃ , 20 ° C)

IR (KBr) 3200-3600,2
960, 2950, 2875, 1610, 1505, 1
480, 1270, 1255, 1162, 1050, 1
020,825 cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 6.7 Hz, 3H), 1.24 to 1.41
(M, 8H), 1.47 (quintet, J = 7.1)
Hz, 2H), 1.54 (s, 1H), 1.80 (qu)
intet, J = 6.5 Hz, 2H), 2.23 (dq
d, J = 14.2, 7.5, and 1.7 Hz, 1
H), 2.64 (ddd, J = 13.6, 7.5, an
d1.9 Hz, 1H), 3.84 to 3.92 (m, 1
H), 3.93 to 4.01 (m, 1H), 3.99.
(T, J = 6.5 Hz, 2H), 6.95 (d, J =
8.8Hz, 2H), 7.26 (d, J = 8.2Hz,
2H), 7.49 (d, J = 8.7Hz, 2H), 7.
51 (d, J = 8.1Hz, 2H)

MS m / z 388 (M ⁺ , 99), 3
76 (30), 256 (45), 245 (58), 22
6 (58), 57 (55), 43 (100)

High resolution MS (M ⁺ ) C ₂₄ H ₃₀ F ₂ O ₂
Calculated value (m / z) 388.2212 Measured value (m / z) 388.2208

(1-g) (-)-trans-1,1-difluoro-2-hydroxymethyl-3- [4- (4-octyloxyphenyl)
Synthesis of [phenyl] cyclopropane

In the embodiment (1-f), the embodiment (1-
Instead of using the non-polar component of the compound obtained in e),
41 mg of polar component of the compound obtained in Example (1-e)
Example (1- except that (0.079 mmol) was used.
In the same manner as in f), white crystals of (-)-trans-1,
1-difluoro-2-hydroxymethyl-3- [4-
25 mg (yield 82%) of (4-octyloxyphenyl) phenyl] cyclopropane was obtained.

Melting point: 124 ° C.

[Α] _D −21.3 ° (c = 0.59,
CHCl ₃ , 20 ° C)

IR (KBr) 3200-3600,2
960, 2950, 2875, 1610, 1505, 1
480, 1270, 1255, 1162, 1050, 1
020,825 cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 6.7 Hz, 3H), 1.24 to 1.41
(M, 8H), 1.47 (quintet, J = 7.1)
Hz, 2H), 1.54 (s, 1H), 1.80 (qu)
intet, J = 6.5 Hz, 2H), 2.23 (dq
d, J = 14.2, 7.7, and 1.7 Hz, 1
H), 2.64 (ddd, J = 13.6, 7.4, an
d1.7 Hz, 1H), 3.84 to 3.92 (m, 1
H), 3.93 to 4.01 (m, 1H), 3.99.
(T, J = 6.5 Hz, 2H), 6.95 (d, J =
8.8Hz, 2H), 7.26 (d, J = 8.2Hz,
2H), 7.49 (d, J = 8.7Hz, 2H), 7.
51 (d, J = 8.2Hz, 2H)

MS m / z 388 (M ⁺ , 99), 3
76 (30), 256 (45), 245 (58), 22
6 (58), 57 (55), 43 (100)

High-resolution MS (M ⁺ ) C ₂₄ H ₃₀ F ₂ O ₂ Calculated value (m / z) 388.2212 Measured value (m / z) 388.2204

(1-h) (+)-trans-1,1-difluoro-2-hexyloxymethyl-3- [4- (4-octyloxyphenyl) phenyl] cyclopropane (represented by the general formula (I) No. 1 compound in Table 1)

[0123]

[Chemical 19]

Compound 14m obtained in Example (1-f)
g (0.036 mmol) in 0.5 ml of DMF,
After adding 16 μl (0.11 mmol) of hexyl iodide, 18 mg (0.72 mmol) of sodium hydride was further added at 0 ° C., and the mixture was stirred at room temperature for 2 hours. After the reaction,
The reaction solution was poured into 20 ml of 1M hydrochloric acid, the reaction product was extracted three times with 10 ml of ether, and the extract was washed with 10 ml of a saturated aqueous sodium hydrogen carbonate solution and then with 10 ml of saturated saline.
Washed with. Further, this extract was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was separated and purified using thin layer chromatography (developing solvent: hexane / ethyl acetate = 2/1) to give (+)-trans-1,1-difluoro-2-hexyloxymethyl as white crystals. 15 mg of -3- [4- (4-octyloxyphenyl) phenyl] cyclopropane (yield 89
%) Was obtained.

Melting point: 55 ° C.

[Α] _D + 22.7 ° (c = 0.6, C
HCl ₃ , 20 ° C)

IR (KBr) 2950,2910,2
850, 1605, 1500, 1470, 1240, 1
280, 1172, 1120, 1025, 1010, 9
92,820 cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 6.9 Hz, 6H), 1.26 to 1.40
(M, 14H), 1.47 (quintet, J = 6.
9Hz, 2H), 1.60 (quintet, J = 6.
8 Hz, 2H), 1.80 (quintet, J = 6.
8Hz, 2H), 2.17 (sextet, J = 7.6)
Hz, 1H), 2.57 (dd, J = 14.2, 7.6)
Hz, 1H), 3.45 (dt, J = 9.2 and 6.
6 Hz, 1 H), 3.52 (dt, J = 9.2 and
6.6 Hz, 1 H), 3.63 (ddd, J = 11.1.
0,7.6, and 1.6Hz, 1H), 3.74 (d
dd, J = 11.0, 6.4, and 1.9 Hz, 1
H), 3.99 (t, J = 6.6 Hz, 2H), 6.9.
5 (d, J = 8.8 Hz, 2H), 7.26 (d, J =
8.2Hz, 2H), 7.49 (d, J = 8.7Hz,
2H), 7.50 (d, J = 8.2Hz, 2H)

MS m / z 472 (M ⁺ , 37), 3
57 (60), 43 (100)

[0130] Elemental _{analysis: C 30 H 42 F 2 O} 2 Calculated: C, 76.23%; H, 8.95% Found: C, 76.10%; H, 9.13%

(1-i) (-)-trans-1,1-difluoro-2-hexyloxymethyl-3- [4- (4-octyloxyphenyl) phenyl] cyclopropane (represented by the general formula (I) No. 2 compound in Table 1)

In Example (1-h), Example (1-h)
Instead of using the compound obtained in f), the compound of Example (1-
23 mg (0.059 mmol) of the compound obtained in g)
In the same manner as in Example (1-h) except that the above compound was used, white crystals of (-)-trans-1,1-difluoro-2-hexyloxymethyl-3- [4- (4-octyloxyphenyl) were used. ) Phenyl] cyclopropane 23 mg (yield 8
4%).

Melting point: 53 ° C.

[Α] _D −21.9 ° (c = 0.81,
CHCl ₃ , 20 ° C)

IR (KBr) 2950,2910,2
850, 1605, 1500, 1470, 1240, 1
300,1178,1110,968,815cm ^-1

¹ H NMR (CDCl ₃ ) δ 0.89
(T, J = 6.9 Hz, 6H), 1.26 to 1.40
(M, 14H), 1.47 (quintet, J = 6.
9Hz, 2H), 1.60 (quintet, J = 6.
8 Hz, 2H), 1.80 (quintet, J = 6.
8Hz, 2H), 2.17 (sextet, J = 7.6)
Hz, 1H), 2.57 (dd, J = 14.2, 7.6)
Hz, 1H), 3.45 (dt, J = 9.2 and 6.
6 Hz, 1 H), 3.52 (dt, J = 9.2 and
6.6 Hz, 1 H), 3.63 (ddd, J = 11.1.
0,7.6, and 1.6Hz, 1H), 3.74 (d
dd, J = 11.0, 6.4, and 1.9 Hz, 1
H), 3.99 (t, J = 6.6 Hz, 2H), 6.9.
5 (d, J = 8.8 Hz, 2H), 7.26 (dd, J
= 8.2 Hz, 2H), 7.49 (d, J = 8.7H)
z, 2H), 7.50 (d, J = 8.2Hz, 2H)

MS m / z 472 (M ⁺ , 27), 3
57 (46), 43 (100)

High-resolution MS (M ⁺ ) C ₃₀ H ₄₂ F ₂ O ₂ Calculated value (m / z) 472.3150 Measured value (m / z) 472.3167

Example 2 Preparation of Sc ^* Liquid Crystal Composition A base liquid crystal (H-1) having a Sc phase having the following composition was prepared.

[0140]

[Chemical 20]

The phase transition temperature of this host liquid crystal (H-1) was as follows. 12.5 ° C. (Cr → Sc), 55.
_{5 ℃ (Sc-S A)} , 64.5 ℃ (S A -N), 70 ℃
(N-I).

95% of the base liquid crystal (H-1) and No. 1 in Table 1 obtained in Example 1 were obtained. A Sc ^* liquid crystal composition (M-1) consisting of 5% of the compound of 1 was prepared. The phase transition temperature was as follows.

[0143] _{^{51.0 ℃ (Sc * -S A)}} , 63.5 ℃
^{_{(S A -N *), 65.5}} ℃ (N * -I). The melting point was not clear.

Similarly, 90% of the base liquid crystal (H-1) and No. 1 in Table 1 obtained in Example 1 were obtained. Compound 10 of 1
% Sc ^* liquid crystal composition (M-2) was prepared. The phase transition temperature was as follows.

[0145] _{^{45.5 ℃ (Sc * -S A)}} , 60.0 ℃
(S _A -I).

Similarly, 95% of the base liquid crystal (H-1) and No. 1 in Table 1 obtained in Example 1 were obtained. 2% compound 5%
A Sc ^* liquid crystal composition (M-3) was prepared. The phase transition temperature was as follows.

[0147] _{^{49.5 ℃ (Sc * -S A)}} , 63.5 ℃
^{_{(S A -N *), 65.0}} ℃ (N * -I).

Similarly, 90% of the base liquid crystal (H-1) and No. 1 in Table 1 obtained in Example 1 were obtained. Compound 10 of 2
% Sc ^* liquid crystal composition (M-4) was prepared. The phase transition temperature was as follows.

[0149] _{^{45.5 ℃ (Sc * -S A)}} , 60.0 ℃
(S _A -I).

Example 3 Preparation of Liquid Crystal Display Device The Sc ^* liquid crystal composition (M-1) obtained in Example 2 was heated to the isotropic liquid (I) phase, and this was heated to a thickness of 2 μm. A liquid crystal display device was prepared by filling a glass cell composed of a sheet of transparent electrode plates (each of which was subjected to orientation treatment by polyimide coating-rubbing). When this was gradually cooled to room temperature, a uniformly aligned Sc ^* phase liquid crystal display device was obtained.

This liquid crystal display device has an electric field strength of 10 V _pp /
When a rectangular wave of μm, 50 Hz was applied and the electro-optical response speed was measured, a high-speed response of 105 μsec at 25 ° C. was confirmed. At this time, the tilt angle was 18.6 °, and the contrast was good. The spontaneous polarization was −2.9 nC / cm ² .

Similarly, the Sc ^* liquid crystal composition (M-
A liquid crystal display device was prepared using 2), (M-3) and (M-4), and its characteristics were measured. The results are shown below.

(M-2): Response speed 52 μsec, tilt angle 17.3 °, spontaneous polarization −9.8 nC / cm ² , good contrast.

(M-3): Response speed 130 μsec, tilt angle 16.3 °, spontaneous polarization +3.2 nC / cm ² , good contrast.

(M-4): Response speed 38 μsec, tilt angle 18.3 °, spontaneous polarization +9.5 nC / cm ² , good contrast.

[0156]

INDUSTRIAL APPLICABILITY The optically active difluorocyclopropane derivative represented by the general formula (I) of the present invention can induce a large spontaneous polarization by adding a small amount as a chiral dopant to a Sc matrix liquid crystal, and has a wide temperature range. so,
It is possible to provide a Sc ^* liquid crystal composition capable of high-speed response.

Further, the compound represented by the general formula (I) of the present invention can be easily produced industrially, is colorless and has excellent chemical stability against water, light and the like, and is practical.

Furthermore, the chiral smectic liquid crystal composition of the present invention can realize a high-speed response of 50 μsec or less, and is extremely useful as an optical switching element for display.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C07D 239/26 7038-4C 241/12 6701-4C 319/06 7729-4C C09K 19/30 6742- 4H 19/44 6742-4H G02F 1/13 500 8806-2K (72) Inventor Taejiro Hiyama 4-29-3-101 Kamizuruma, Sagamihara City, Kanagawa Prefecture (72) Inventor Tetsuo Kusumoto Minamidai, Sagamihara City, Kanagawa Prefecture 1- 9-2-102 (72) Kenichi Sato 35-11 Kamimizo, Sagamihara City, Kanagawa Prefecture

Claims (8)

[Claims] 1. A compound represented by the general formula (I): (In the formula, R ¹ represents an alkyl group having 1 to 18 carbon atoms, X represents a single bond or —O—, and the ring A and the ring B are each independently a 1 or 2 fluorine atom. Optionally substituted 1,4-phenylene group, trans-
1,4-cyclohexylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, pyrazine-2,
5-diyl group, pyridazine-3,6-diyl group or 1,
Represents a 3-dioxane-2,5-diyl group, m represents 0 or 1, and R ² represents a fluorine atom or a carbon atom number of 1 to 1.
Represents an alkyl group having 1 to 18 carbon atoms which may be substituted by an alkoxyl group of 0, and the asymmetric carbon atoms at the 2- and 3-positions of the cyclopropane ring are each independently (R) or (S ) Arrangement. ) An optically active difluorocyclopropane derivative represented by 2. The optically active difluorocyclopropane derivative according to claim 1, wherein m = 0 and ring B is a 1,4-phenylene group optionally substituted by one or two fluorine atoms. 3. The optically active difluorocyclopropane derivative according to claim 2, wherein R ¹ is a linear alkyl group having 2 to 12 carbon atoms. 4. The optically active difluorocyclopropane derivative according to claim 3, wherein R ² is a linear alkyl group having 1 to 10 carbon atoms. 5. The optically active difluorocyclopropane derivative according to claim 4, wherein X is —O—. 6. A liquid crystal composition containing the optically active difluorocyclopropane derivative according to claim 1, claim 2, claim 3, claim 4 or claim 5. 7. The liquid crystal composition according to claim 6, which exhibits a ferroelectric chiral smectic phase. 8. A liquid crystal display device using the liquid crystal composition according to claim 6.