JPH01131134A - Optical active lactic acid derivative and liquid crystal composition containing the same - Google Patents

Abstract

NEW MATERIAL:A compound of formula I (R1 is 1-16C alkyl; R2 is 2-16C alkyl, rings A, B, C and D are formulas VII, VIII or formula IX; Y is -COO-, -OCO-, single bond; 1, m, n are 0, 1; k is 0-6; * is asymmetric carbon). EXAMPLE:4-[(S)-2-Propoxypropanoyloxy]phenyl 4'-[(S)-(2)- methylbutoxy]biphenyl-4-carboxylate. USE:Ferroelectric liquid crystal composition. It has high possibility of application to liquid crystal display elements excellent in response and memorizing properties. PREPARATION:The reaction of a compound of formula IIa where Y is -COO- with another compound of formula VI gives a compound of formula IIIa, then, the product is converted into its acid chloride,. Then, the chloride is allowed to react with formula Va to give the subject compound of formula Ia among those of formula I.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a novel optically active lactic acid derivative useful as an electro-optical display material and a liquid crystal composition containing the compound, and in particular to a liquid crystal composition having ferroelectric properties. The present invention provides a liquid crystal material that can be used for liquid crystal display elements, and has particularly excellent responsiveness and memory performance compared to conventional liquid crystal materials.

[Prior art]

The currently widely used liquid crystal display elements are mainly of the TN type, which utilizes nematic liquid crystals, and although they have many advantages, their responsiveness is inferior to that of light-emitting types such as CRTs. Compared to the display method, the major drawback was that it was much slower. Many liquid crystal display systems other than the TN type have been studied, but improvements in their responsiveness have not yet been achieved.

However, display elements using ferroelectric smectic liquid crystals can respond 100 to 1000 times faster than conventional devices, and have multistability, so they can retain the display even when the power is turned off (memory effect). This has recently become clear. For this reason, it has great potential to be used in optical shutters, printer heads, flat-screen televisions, etc., and research and development is currently being conducted in various fields to put it into practical use.

The liquid crystal phase of ferroelectric liquid crystals belongs to the tilted chiral smectic phase, and among them, the one that is practically desirable is chiral smectic C (hereinafter abbreviated as Sc), which has the lowest viscosity. ) phase.

Liquid crystal compounds exhibiting an "sc" phase (hereinafter abbreviated as "sc" compounds) have been studied and many compounds have already been synthesized. However, these Sc* compounds alone must meet the following conditions for use as a ferroelectric liquid crystal display element: (a) exhibiting ferroelectricity in a wide temperature range including room temperature; and (b) exhibiting ferroelectricity in a high temperature range. Having an appropriate phase series (/
In particular, the chiral nematic (N) phase should exhibit a long helical pitch) It should have an appropriate tilt angle (E) It should have low viscosity (F) It should have a large spontaneous polarization above a certain level (G) ( There is no known product that satisfies the following: exhibiting good orientation as a result of b) and shi → ('F), and exhibiting high-speed responsiveness as a result of (e) and (f). .

Therefore, at present, liquid crystal compositions having an SC* phase (hereinafter abbreviated as Sc* liquid crystal compositions) are currently being used for study purposes.

Methods for preparing SC liquid crystal compositions include (a) a method of mixing a plurality of "sc"compounds; and (b) a non-chiral smectic C that does not exhibit ferroelectricity.
(hereinafter abbreviated as SC).A liquid crystal compound or composition exhibiting a phase (hereinafter referred to as the base SC liquid crystal composition) has a chiral chemical reaction '@ (hereinafter referred to as chiral do gunt).
However, the former method increases the viscosity of the composition, making it difficult to achieve a high-speed response, and the latter method is more common.

[Problem to be solved by the invention]

However, there are many restrictions on the chiral dopants used in the latter. First of all, Kairaldo Mother herself,
It is necessary to have a very large spontaneous polarization or to be able to induce a very large spontaneous polarization. Otherwise, Sc
*In order to lower the viscosity of the liquid crystal composition, the amount of chiral dopant added must be small;
This is because the spontaneous polarization of the Sc* liquid crystal composition becomes too small. Next, chiral dopants have a torsional force on the ♂ phase and the sc'' phase as well as spontaneous polarization, and compounds that can exhibit particularly strong spontaneous polarization tend to have a strong twisting force.Especially N If the helical pitch in the phase becomes small, it will have a negative effect on the orientation, so a chiral compound with the opposite twist direction is added to increase the helical pitch (particularly in the N* phase) of the Sc* liquid crystal composition. In this case, if the direction of the spontaneous polarization of the compound with the opposite twist direction is also opposite, or if the direction is small even if it is in the same direction, then the spontaneous polarization of the chiral dopant as a whole There were many troublesome problems in adjusting the helical pitch, such as the polarization becoming small.

Furthermore, although it is not necessarily necessary for the chiral dopant to exhibit a liquid crystal phase, in order to avoid narrowing the temperature range of the SC liquid crystal composition, it is desirable that the chiral dopant exhibit a liquid crystal phase, especially a tilted chiral smectic phase. It is advantageous if the material exhibits the S♂ phase up to a high temperature range.

Therefore, there has been a desire for a chiral liquid crystal compound that can exhibit large spontaneous polarization, has a large helical pitch, and exhibits an S♂ phase by itself as much as possible up to high temperatures.

The problem to be solved by the present invention is that it has a large spontaneous polarization, a large helical pitch compared to the optical component, and also exhibits a tilted chiral smectic phase. The object of the present invention is to provide a novel chiral compound that exhibits an SC* phase and is capable of high-speed response.

[Means for solving problems]

In order to solve the above problems, the present invention provides - Formula (1) % formula % (1) The compound represented by (hereinafter abbreviated as compound (1))

)I will provide a.

In the above formula, R4 represents an alkyl group having 1 to 16 carbon atoms, but if the number of carbon atoms is small, the spontaneous polarization of compound '(I) will be small, and if the number of carbon atoms is large, the viscosity will tend to be high. Preferably it is an alkyl group having 3 to 8 carbon atoms.

InIn each independently represents O or 1, but m
When = n = O, the liquid crystallinity of compound (1) is poor, and when m = n = 1, the viscosity becomes insular, so m = 1゜n =
0 or m=Q, nxl, that is, compound (1)
is preferably tricyclic.

t represents 0 or 1, and represents an integer of 1 to 6, with 0 or 1 being particularly preferred. R2 represents an alkyl group having 2 to 16 carbon atoms, and is particularly preferably an alkyl group having 2 to 6 carbon atoms.

C″ and C″11 each independently have an absolute configuration of (S)
Alternatively, it represents an asymmetric carbon atom with the (R) configuration, but the (S) configuration is preferred in consideration of the ease of obtaining raw materials.

Y represents -COO-, -0CO-, or a single bond.

The compound of formula (1) according to the present invention can be produced, for example, by the following production method.

(1) If Y represents -coo-, the oath
- 趶輔= (Formula (ff)a above, (III)a, (IV)a,
(V) R1゜R,c'' at a, C**, ■, ■
, ■, ■, In m net, each have the same meaning as in formula (1)) By reacting the hydroxycarboxylic acid of formula (n) a with the acid chloride of the lactic acid derivative of formula (M), A carnic acid of formula (III)a is prepared. This was reacted with thionyl chloride and the formula (■
) The compound of formula (1-a) can be produced by reacting the n4 optically active phenol of formula (V) a after forming the acid chloride of a. Also Cm) a and (V)
It can also be produced by directly esterifying dicyclohexylcar from a with a dehydration condensation agent such as diimide.

(ii) When y represents 10CO-/7noヱυ (In the above formula (II)b, (I[I)b, (V)b, R1+ R2*C*, C**, ■ ,■+O*
OD * fn * n + 1- * is expressed by formula (1)
Hydroquinone (if m = 0) or biphenol (if m = 1) of formula (If) b (each having the same meaning as in formula (■)) or a substituted product thereof
The phenol derivative of formula (III) b is produced by reacting with an acid chloride which is a lactic acid derivative of By reacting this with an optically active acid chloride of formula (V)b, a compound of formula (1-b) can be produced. (
Similarly to 1), (V) Cal ? corresponding to b? acid and (1
) It can also be produced by directly esterifying b.

(+i+) When y represents a single bond, an optically active phenol (for example, if compound (1) is a two-ring type, the formula (V)
It is sufficient to use the compound of a, and it is sufficient to use 3) to the formula (■
) by reacting the acid chloride of the lactic acid derivative of
can be manufactured.

Each raw material compound used in each step of (+) to (111) can be obtained, for example, as follows.

Hydroxycarboxylic acid of formula (]) a 1 Phenol or biphenol of formula (If) b is partially commercially available, but if necessary, an aninol derivative represented by the following formula (■) can be acetylated and By treatment with performic acid followed by demethylation, a compound of formula (II)b is obtained by treatment with sodium hypobromite solution followed by demethylation to obtain a compound of formula (II)a. Can be done. Further, the compound of formula (II) a is obtained by brominating the compound of formula ('4) to form a bromide of formula (K), converting it into a Grignard compound with magnesium, and then reacting it with carbon dioxide gas.
Subsequently, demethylation can also be performed to obtain the desired kernels.

When t = The formula (
XI) can be directly reacted with a tosylate of formula (V)a to obtain an optically active phenol of formula (V)a, which can be further treated with thionyl chloride to obtain an optically active acid chloride of formula (V)b. Can be done.

In the case of a compound of formula (V)b, the carboxyl group of formula (II)a is protected as a lower alkylnisyl,
In some cases, reaction with tosylate followed by hydrolysis to give carbic acid gives better yields.

(X) (M) (■)b 1) (XI), base 2) H+(V)a
When Ct=1) Here, many compounds are already commercially available regarding the optically active alcohol (X), especially the (S) form.

In formula (X), alcohols where k is 1 to 5 can be obtained from alcohols where k=o by extending the carbon chain according to a conventional method.

In addition, other synthetic methods have been reported for the (R) form of the compound, and it can be obtained according to these methods.

When 1=0, the compound of formula (V)a is obtained by reacting the compound derived from the compound of formula (■) with tosylate (XI) in the presence of a copper-based catalyst or the like. be able to.

The compound of formula (V)b is obtained by converting the bromide represented by formula (Xll) into a Grignard compound, and then reacting it with tosylate in the same manner as the compound of formula (V)a to introduce a carboxyl group according to a conventional method. can be obtained by

Alternatively, when k is 1 or more, the optically active alcohol is oxidized to give carbic acid, the acid chloride is made with thionyl chloride, this is reacted with a compound of formula (Xll) in the presence of aluminum chloride, and then Wolff- Kiachn
er reduction yoshikaru? The nyl group is reduced to form an optically active bromide represented by the formula. It can also be obtained by converting this into a Grignard compound and then reacting it with carbonic acid.

(■) 1) Mg 2) (Xl)-catalyst 3) HB'
(V)a (t=0 Oja combination) 1) CHsCO
C4AtCt32) NaOBr (v,, (,o)
case.

(X) The compound of formula (■) can be prepared, for example, by using a 4-bromo727yl derivative (CH30-C)Br as a Grignard compound, and in the presence of a catalyst such as radium chloride, formula (xIII)
By reacting with a compound of and demethylating it,
Obtainable.

In each process related to obtaining the above raw materials, -o,
(), o, <I) can also be considered interchangeably. For example, )IoQou (olou) has the same meaning as (olou).

Table 1 lists the transition temperatures of representative compounds of formula (1) thus produced.

The liquid crystal phase and phase transition temperature were measured using a polarizing microscope equipped with a temperature control stage and a differential scanning calorimeter (DSC), but the transition temperature may vary slightly depending on the purity of the sample or measurement conditions. It is something to do.

Confirmation of the structure of a compound can be done using infrared absorption spectrum (IR),
Nuclear magnetic resonance spectrum (MS) and mass spectrum (M
I went to S).

Purity was measured using various types of chromatography such as high performance liquid chromatography.

/ 7/ 271.・″ /′ In Table 1, C is a crystalline phase, SC is a chiral smectic C phase, SA is a smectic human phase, SX is a chiral smectic phase of unknown origin, N9 is a chiral nematic phase, and ■ is an isotropic liquid phase.・represents the existence of that phase, − represents that the phase does not exist, the number to the right of ・represents the transition temperature from that phase to a phase in the vortex region, and the numbers in parentheses indicates that the phase is monotropic. (★) indicates that the phase may exist.

The most significant structural feature of compound (1) is that it is a guichiral compound having asymmetric carbon atoms in both side chains of the molecule. On the other hand, a well-known one is one in which R2 derived from natural (S)-2-methylbutanol is an ethyl group and the absolute configuration of C** is (S). There are commercially available products with R2 other than ethyl group, and synthesis examples have been reported for the (R) form, but considering cost and ease of acquisition, (S)-2-methylbutanol-derived products are available. It is advantageous to use chiral groups. However, in SC* compounds having only this chiral group, the spontaneous polarization is quite small, and at most a nC/
It is also known that cW1. On the other hand, the torsion effect of this chiral group on the liquid crystal phase is that (k+t≦1
) is relatively strong.

The (S) form and (R) form of the other chiral group are both available, but the (S) form is the cheapest.

According to research conducted by the present inventors, it has been confirmed that this compound having a chiral group has a large spontaneous polarization of 100 nC/crR or more. Furthermore, the torsional resistance to the liquid crystal phase is quite strong.

As mentioned above, it is desirable for the chiral compound used in the ferroelectric liquid crystal composition to have as large a spontaneous polarization as possible. In this sense, SC* liquid crystal compositions in which only 10 to 40% of such compounds derived from lactic acid are added have the drawback that the helical pitch becomes too small and it is difficult to obtain good alignment. Therefore, it is necessary to adjust the helical pitch by adding a chiral compound whose torsion force is in the opposite direction.In this case, even if the compound has a reverse torsion, the direction of its spontaneous polarization is the same, or The spontaneous polarization must be negligible, and even if it is, the SC
*It is difficult to avoid a decrease in the spontaneous polarization of the entire chiral compound in the composition.

In addition, in order to obtain good orientation, I (isotropic liquid phase) → N
It is desirable that the phase transition sequence is * (chiral nematic phase) → SA (smectic phase) → SC8, and that the helical pitch of both the N1 phase and the SC* phase is sufficiently large. Adjusting at the same time itself,
It's quite a hassle.

Focusing on the fact that there is no difference in spontaneous polarization between at least 10 to about 100 times as large as the torsional force and the magnitude of the torsional force, in a compound containing both in the same molecule,
While always having a large spontaneous polarization, the contact group +0 辷-(C
We thought that depending on the absolute configuration of H2te and C@, c+I*, and the selection of k, R, and R2, the torsion would cancel each other out and become smaller, resulting in a large spiral and pitch, and we developed the present invention. This is what led to this.

The direction of torsion was right-handed when the absolute configuration of C8 was in the (S) configuration, and was overwhelming in the case where the absolute configuration was in the (R) configuration.

Regarding the direction, if the absolute configuration of C** is (S) body,
It is known that when t+k is O or an even number of 2.4.6, the winding is right-handed, and when t+k is an odd number of 1 or 3,5, the winding is left-handed. In the case of the (R) body, the opposite is true.

Therefore, for example, the absolute configurations of C* and C** are both (S)
In case of body, +0)-7-+CH21 and Chi0-
, -CH2-, -0+CH2+2. +CH2, 1, etc., and when t+k is an odd number, the torsional forces due to both chiral groups are canceled out. The same applies to both (R) forms. The absolute configurations of C* and C** are (R) and (S
) or in the case of (S) and (R), (QpCH2+, single bond, -0-CH2-, +CH2chi2.0(-
When CH2, ÷α29, L+k is an even number, the torsional force is canceled out. However, as t+k becomes large, t0 is preferably about 0 to 2, υ
-CI-1-L: Compared to a liquid crystal compound having only 00 group as a chiral group, the induced helical pitch is much larger.

The absolute configuration of a part of compound (1), t+k,
Table 2 shows the magnitude of the induced helical pitch.

The second helical pitch of the N0 phase and the SC* phase is obtained by adding 10 to 40% of compound (1) to a base SC liquid crystal composition consisting of a phenylbenzoate-phenylpyrimidine system, which will be described later, to obtain an SC0 liquid crystal composition having an N1 phase. It is calculated by measuring it as a physical object and extrapolating it. Therefore, this value does not necessarily match the pitch of compounds that exhibit N9 phase or SC* phase alone; Since it is effective to use it as a donolant, it is very practical. Note that these measurements were performed at a temperature 5° below the transition point. As is clear from Table 2, when the absolute configurations of C8 and C** are both (S), and when K is O or 2, the pitch of the particularly important N* phase is 0.14 to 0. .16
- is very fine, whereas if k is 1, then
When it is large, from 0.7 μm to 3 μm or more, and is added in an amount of 10 to 30% to the base SC liquid crystal composition, a layer with good orientation can be formed.

The helical pitch of the N* phase and the SC* phase of the 9 sc'' liquid crystal composition obtained by adding the compound of Example 1 to the same base SC liquid crystal composition was 18 μm at 79.5° C., respectively.

A large and good orientation of 6.5 μm at 45° C. was confirmed. On the other hand, in the case of the compound of Example 4, the helical pitch of the N* phase of the SC* liquid crystal composition to which 30% was added was 1 μm or less, making it difficult to obtain good orientation.

In the measurement of the spontaneous polarization of compound (1), as well as the helical pitch, the phenylbenzoate-pyrimidine matrix S
SC" obtained by adding 10 to 40
This was done by measuring the spontaneous polarization of the phase and extrapolating from that value. Although this does not directly represent the value of compound (I) alone, it alleviates the influence of the tilt angle on the value of spontaneous polarization, and is very practical when used as a donut's arm. In the compound of Example 1, Tc
-80 nC/cm at T=10°, Te-T=
It showed a large value of 120 nC/m2 at 20°. The measurement results are summarized in Table 3.

Table 3 All of these values are of the same order of magnitude or considerably larger than if they were taken as chiral groups.

As mentioned above, the compound (1) is (0舅CH2+i12
When appropriately selected, SC* has a large spontaneous polarization, a large helical pitch, and good orientation by adding 10 to 40% to the base SC liquid crystal composition.
A liquid crystal composition can be easily obtained.

Moreover, the SC* liquid crystal composition obtained in this way is 1,
As shown in the examples below, it is an extremely excellent compound capable of high-speed response of 100 μsec or less at room temperature.

In general, introducing a branching group into the side chain of a liquid crystal molecule reduces the liquid crystallinity, and the phase transition temperature of the metal is K.
Since compound (1) has branched methyl groups in both side chains, its phase transition temperature is considerably lower than that of compounds with similar skeleton structures, and it is only m that exhibits liquid crystallinity by itself.
-1-a = 3, which is a tricyclic type.

It is effective to use compound (I) as an SC9 liquid crystal composition by mixing it with an SC liquid crystal composition mainly consisting of a low-viscosity liquid crystal compound without a branching group, but in this case, if the chiral compound has liquid crystallinity, There is a point where, if it is not present at all, the clearing point of the composition will be significantly lowered. Furthermore, when the chiral compound is of the four-ring type, the liquid crystallinity is high and the transition point is high, but there is also the problem that the viscosity becomes extremely high. Therefore, the most preferred compound (1) is a tricyclic type. Furthermore, if the chiral compound does not have chiral smectic properties, the temperature range of the SC'' phase in the composition tends to be narrowed.

Compound (1) is characterized in that most of it exhibits a chiral smectic phase, and the temperature range of the SC* phase is hardly narrowed during mixing.

As the liquid crystal compound to be used in the base SC liquid crystal composition, for example, phenylbenzoate compounds (A) and phenylpyrimidine compounds (B) as shown below can be used.

(wherein R1 and R6 are linear or branched alkyl groups,
Alkoxy group, alkylcargenyloxy group, and alkoxycal represent a nyl group and an alkoxycargenyloxy group. Examples of the branched group include a methyl group and fluorine. - and R5 are particularly preferably linear alkyl or alkoxy groups.

Introduction of branching groups is also effective for lowering the melting point. ) Also, compounds represented by the general formula (C), including (A) and (B), can be used for the same purpose.

(In the formula, R1 and 9 are the same as above, and X is -COO
-, -0CO-, -CI(20-, -0CI(2-, -
CH2CH2-.

-C-th C- or represents a single bond. ) A base SC liquid crystal composition with low viscosity can also be obtained by mixing these bicyclic compounds, but when it is desired to further expand the temperature range of the SC phase, especially to a high temperature range, the general formula (
A tricyclic compound represented by D) can be effectively used.

() and 0 are the same as the above-mentioned building and association. Xl and X2 are the same as the above-mentioned X, but it is desirable that at least one of them is a single bond. ) Above (A) ~ (
It is sufficient for the compound D) to exhibit an SC phase as a composition, and it is not necessary for all individual compounds to exhibit an SC phase.

Further, even compounds other than (A) to (D) can be used for purposes such as reducing the viscosity of the composition as long as they are liquid crystalline compounds with low viscosity.

The obtained liquid crystal compound or composition can be used as a liquid crystal display cell by forming a thin film with a uniform thickness (1 μm to 20 μm at degrees) between two transparent electrode plates.

In a display cell, liquid crystal molecules need to be homogeneous monodomains with the long axis of the molecules parallel to the electrode plane, with uniform orientation. For this purpose, the surface of the electrode plate is subjected to an alignment treatment such as rubbing or vapor deposition, or an electric field or a magnetic field is applied, a temperature gradient is created, or a combination of these methods is used to achieve isotropic alignment. Generally, a method is employed in which the liquid crystal phase (I) is gradually cooled down to the liquid crystal phase for orientation.

In particular, recently, cells that have been subjected to an alignment treatment have been developed with liquid crystals that exhibit a phase sequence of isotropic liquid phase (I) → chiral nematic phase (N*) → smectic A phase (SA) → chiral smectic C phase (sc”). In particular, a method of aligning by increasing the helical pitch of the N'' phase is often used, and the same method can be used for the SC'' liquid crystal composition containing about 10 to 30 compounds of the formula (R) of the present invention. In a good way,
Uniformly oriented monodomain cells can be easily obtained.

〔Example〕

The present invention will be specifically explained below with reference to Examples, but of course the gist and scope of the present invention are not limited by these Examples.

Example 1 Synthesis of 4-((S)-2-glopoxyzolonono-9noyloxy)phenyl 4'-((S)-2-methylbutoxy)piphenyl-4-carboxylate 1-a)
4'-((S)-2-methylbutoxy)piphenyl-4-cal? synthesis of 4'-hydroxybiphenyl-4-carnoic acid 6,24
It was dissolved in 11t-dimethyl sulfoxide group 50, and 2.909 g of Kt-butoxypotassium was added to this solution under water cooling, and the mixture was stirred. In this solution, (S)-2 synthesized from (S)-2-methylbutanol and p-)luenesulfonyl chloride was added.
-Methylbutyl p-)luenesulfonate 7.0N
was dissolved in 59ml of tetrahydrofuran and added dropwise over 1 hour. The mixture was further stirred at room temperature for 30 minutes. After making the reaction solution acidic with hydrochloric acid, it was extracted with ether, and the crude crystals obtained by distilling off the ether were recrystallized from hexane to give 4'-((S) -
7.5y of 2-methylbutoxy)biphenyl-4-cargenic acid ethyl ester was obtained. This was processed into ethanol 15 (Il) in which 2 sodium hydroxide and OI were dissolved, and heated and dissolved. After refluxing for 6 hours, it was allowed to cool, and the precipitated crystals were separated from each other. The crude crystals were recrystallized twice from benzene. Let me,
4'-((S)-2-methylbutoxy)biphenyl-
5.5 g of white crystals of 4-cargenic acid were obtained.

1-b) 4-hydroxyphenyl (S) -2-
Probyloxyglopionate (S)-ethyl lactate 20.0,51. Globil iodide 4
5.0.9 and 30.0 g of silver oxide were stirred in 100-dimethylformamide for 40 hours. Insoluble materials were separated from each other, water was added to the p-liquid, and the mixture was extracted three times with hexane. After dehydrating the hexane layer, it was distilled under reduced pressure to give 20% ethyl (S)-2-propoxyglopionate. I got OE'c. (78°150
Hg) This 18.0.9 was stirred in 100ml of 5N sodium hydroxide aqueous solution for 6 hours, and then diluted with water-cooled royal sulfuric acid at -3
~4. After extraction with ether several times, it was dehydrated and the solvent was distilled off to obtain 10.2F (S)-2-propoxypropionic acid. To this mixture, 20 g of thionyl chloride and 0.5 g of pyridine were added and heated under reflux for 2 hours. Excess thionyl chloride was distilled off under reduced pressure, and benzene was added.
After all the insoluble matter was removed, benzene was distilled off and the oily (S)
-2-Propoxypropionic acid chloride 10.5.9 was obtained.

9.0 g of hydroquinone dissolved in 50 rnl of pyridine was added to this 6.0# and stirred at 30-40° for 20 hours. Ethyl acetate was added, and the mixture was washed successively with 10% hydrochloric acid, water, and saturated brine, and then dehydrated over anhydrous sodium sulfate.

After concentration, the target product was separated by silica duplex column chromatography (developing solvent: hexane-ethyl acetate) to obtain 4.9 g of oily 4-hydroxyphenyl (S)-2-propoxypropionate.

1-c) Synthesis of the title compound 4'-((S) -2-methylbutoxy)piphenyl-4-carmenic acid obtained in 1-) 3.20. ! ilK
1.0 g of thionyl chloride 20m pyridine was added, and the mixture was heated and stirred for 3 hours. Excess pyridine was distilled off, toluene was added, and insoluble matter was filtered out. Toluene was distilled off and 4'-((
S) -2-methylbutoxy)piphenyl-4-carbic acid chloride 3.30.9 was obtained.

To 0.50.9 of this, 0.38.9 of 4-hydroxyphenyl (S)-2-fropipoxygropione-) obtained in 1-b) was dissolved in 10 LA' of methylene chloride and added. Ta. 1.0 g of pyridine was added and the mixture was allowed to react under reflux for 2 hours. After cooling, ethyl acetate was added, and the mixture was washed successively with 10% hydrochloric acid, saturated sodium bicarbonate, water, and saturated brine. After dehydration with anhydrous sodium sulfate, the solvent was distilled off, and the resulting composition was purified by silica glu column chromatography, developing solvent: chloroform-hexane), and recrystallized from Salanietta/L to obtain 4-((S). )-2-7'
Ropoxyzolonoyloxy)phenyl 4'-((
4.16N of white crystals of S) -(2)-methylbutoxy)piphenyl-4-cartoxylate were obtained. The phase transition temperatures are shown in Table 1.

Examples 2 to 6 In Example 1, 4'-hydroxypiphenyl-4-carboxylic acid ethyl ester in 1-a) was replaced with 4-hydroxybenzoic acid methyl ester, and hydroquinone i4 in 1-b) was replaced with 4'-biphenol. 4'-((S)-2-propoxyderonoyloxy)piphenyl-4-yl 4-((S)
-2-methylbutoxy) Henshade was obtained. (Example 2) Furthermore, by using octyl iodide instead of propyl iodide in Example 2, 4'-((S)-2
-octoxyprogunoyloxy)piphenyl-4-
yl 4-((S)-2-methylbutoxy)benzoate was obtained. (Example 3) In addition, in Example 1, 4'-((S)-2-methylbutoxy)piphenyl-4-carboxylic acid was replaced with 4'
By using -((S)-2-methylbutyl)piphenyl-4-carboxylic acid (synthesized from commercially available 4'-((S)-2-methylbutyl)-4-cyanopiphenyl), 4- ((S) -2-propoxypro/'P
noyloxy)phenyl 4'-((S) -2-methylbutyl)piphenyl-4-carboxylate (Example 4) and also the intermediately obtained 4-((
By using commercially available 4-((S)-2-methylbutyl)benzoic acid chloride in place of S)-2-methylbutoxy)benzoic acid chloride, 4'-((S)-2-octo xypropanoyloxy)piphenyl-4-yl4
-((S)-2-methylbutyl)benzoate was obtained.

(Example 5) Also, in place of 4-((S)-2-methylbutoxy)benzoic acid obtained as an intermediate in Example 3, (1) bromination (
2) Cyanation with cyanide steel (3-fluoro-4-((S)- produced through each step of hydrolysis of 3-cyano group (4)-OI((S)-2-methylbutylation)
By using 2-methylbutoxy)benzoic acid,
4'-((S) -2-octoxypropanoyloxy)biphenyl-4-yl 3-fluoro-4-((S)
-2-methylbutoxy)penzonite was obtained. (Example 6) Example 7 4-((S)-2-methylbutoxy)phenyl 4'
-((S) -2-propoxypro9noyloxy)
Synthesis of biphenyl-4-carboxylate 7-a)
Synthesis of 4'-((S)-2-propoxypro9noyloxy)biphenyl-4-carmenic acid (S)-2-propoxypropionic acid chloride obtained in step 2-b) 5.27.9 pyridine 35d and methylene chloride; /2
4'-Hydroxybiphenyl-4 dissolved in 011!7
- It was added dropwise into calgenic acid 7.06II, and after the completion of the dropwise addition, the mixture was reacted at reflux temperature for 6 hours. After the reaction was completed, a small amount of ethanol was added to esterify the unreacted acid chloride, dilute hydrochloric acid was added to make it weakly acidic, and the mixture was extracted with ether. A mixed solvent of n-hexane and ether was added to the crude crystals obtained by distilling off the solvent and heated to reflux temperature to remove insoluble 4'-hydroxypiphenyl-4-carmenic acid.
After cooling to 0°C, the precipitated crystals were counted. This recrystallization operation was further repeated to obtain 4.4811 white crystals of 4'-((s)-2-propoxygulono-4-noyloxy)biphenyl-4-carmenic acid.

This compound showed a liquid crystal phase. Its melting point was 155°C and its clearing point was 220°C.

7-b) Synthesis of the title compound Thionyl chloride 15- was added to 4.48.9 of the nine carboxylic acid obtained in 7-a), and while stirring, pyridine 2i-1 was added. After dissolving, it was heated to 40 to 50°C and reacted for 3 hours.

Excess thionyl chloride was distilled off, toluene was added to the residue, and the mixture was thoroughly stirred. After removing insoluble matter by t-filtration, the solvent was distilled off again to obtain 4.50 g of oily 4'-((S)-2-propoxygulono-4noyloxy)biphenyl-4-carmenic acid chloride. .

This acid chloride 33019 was dissolved in 154 methylene chloride and synthesized from hydroquinone and (S)-2-methylbutyl p-)luenesulfonate. 4- (
(S)-2-methylbutoxy)phenol 190rI
I9 and pyridine 1. Od was added, and the mixture was reacted for 3 hours under reflux of the solvent. The same post-treatment and purification operations as in Example 1 were performed to obtain 335 da of white crystals of the title compound.

Example 8 In the same manner as in Example 7, 4-((( S) -3-methylpentoxyphenyl
4'-((S)-2-broxygulono-9noyloxy)biphenyl-4-carboxylate was obtained.

Example 9 In Example 71, (S) -2-octoxypropionic acid chloride was used in place of (S) -2-propoxypropionic acid chloride, and 4'-hydroxypiphenyl-4
-3'-fluoro-4'-((S) -2-octoxypro/f-noyloxy) except that 3'-fluoro-4'-hydroxypiphenyl-4-carmenic acid was used in place of carmenic acid. Biphenyl-4-carmenic acid was obtained.

Using this, 4-((S)
-2-methylbutoxy)phenyl3'-fluoro-4'
-((S)-2-7'ropoxygulono-9noyloxy)
Biphenyl-4-carboxylate was obtained.

Examples 10 to 14 Similarly, 4-((S)-2-methylbutoxy)biphenyl-4-yl 4-((S)-2-glopoxyglopanoyloxy)benzoate (Example 10), r-
((S)-2-methyloctoxy)biphenyl-4-
yl 4-((S)-2-fropoxygulonosenoyloxy)benzoate (Disaster 2It Example 11), 4-((
S) -2-methylbutyl)phenyl 4'-((S)
-2-froIxiderono4noyloxy)biphenyl-
4-carboxylate (Example 12), 4-((S)
-3-methylpentyl)phenyl 4' -((S)-
2-Glopoxyglopanoyloxy)biphenyl-4-
Carboxylate (Example 13), 4'-((S)-2
-methylbutyl)biphenyl-4-yl 4- <(S
)-2-protunoyloxy)benzoate (Example 14) were obtained.

Example 15 (S)-2-octoxypropionic acid chloride and 4-
(4-((S)-2-methylbutoxy)phenyl)phenol was reacted in the same manner, and 4-((S)-2-
Methylbutoxy)phenyl(S)-2-octoxyglopanoate was obtained. (Example 15) The phase transition temperatures of each compound of Examples 2 to 15 are summarized in Table 1 above.

Implementation J16 SC" Preparation of liquid crystal composition/acid 7 and creation of display element Among the ferbenzoate compounds indicated by A in the text, R1 and R2 are both alkoxy, and 4 components (R,
=C,. R2,0, R2=C8H,, Oe 10!
-%: R,=C,H,,O,R2=C6H1,0
, 10%; R,= C8H,,0, R2= C,.

R2, 0, 10 heavy rat; R, = R2〒C8H,, 0, 1
0'! amount%) and the four pyrimidine components (R3
=C8H17,R4=C4゜H210124M child:
R5=CBH17* R4=C2H,,0,27% by weight
: R5=C8H, , R4=C6)1. ．． 0, 6
Company i%; R3=C7H,2, R4=C7H,,0,3
(hereinafter referred to as base SC liquid crystal composition A)
It is abbreviated as ) was prepared. This base SC liquid crystal composition exhibits an SC phase at temperatures below 65°C, an SA phase up to 67°C, and an SA phase at 72°C.
The nematic (hereinafter abbreviated as N) phase is shown in each case. Further, the melting point of this base SC liquid crystal composition was 5°C. An SC liquid crystal composition consisting of 70% by weight of this SC liquid crystal composition and 30% by weight of the compound obtained in Example 1 was prepared.
- Prepared. This SC* liquid crystal composition exhibited an SC* phase at temperatures below 53.5°C, an SA phase up to 79°C, and an N* phase up to 83.5°C. Moreover, the melting point of this SC* liquid crystal composition was 00 or less.

N of this SC* liquid crystal composition at 79.5°C and 80°C
The helical pitches of the phases are large, 18 μm and 16.5 μm, respectively, and the helical pitches of the SC* phase are also 6.5 μm and 2 μm at 45°C.
I rarely found one that was as large as 6 μm or more at 5°C.

This SC1 liquid crystal composition is heated to form an isotropic liquid phase, which is then connected to two glass transparent electrodes (one of which has been subjected to polyimide rubbing alignment treatment) via a 2.0 μm thick spacer. The space was filled to create a thin film cell.

This was gradually cooled at a rate of 5°C per minute, and the N* phase and S
The A phase was oriented to obtain a uniform SC* phase monodomain at 53.5° C. or lower. The orientation was very good.

A 20 V, 50 Hz rectangular wave was applied to this cell, and the intensity of the transmitted light was measured.
A high-speed response of 93 μsec at ℃ and 100 μsec at 25℃ was confirmed. Moreover, the spontaneous polarization at 25°C is 17n
It showed a large value of C/α2, and the tilt angle was 21°.

Example 17 SC liquid crystal composition A76 weight: 26% of the compound of Example 7
SC" liquid crystal composition was prepared by adding F% by weight.
``g-crystalline acid showed SC0 phase at 67' or less.

Using this liquid crystal composition, a display cell was prepared in the same manner as in Example 16.

Apply a 20V/50Hz square wave to this cell,
When we measured its transmission speed, we found that the response speed at 30°C was extremely fast at 57 μs, and the tilt angle was 32.4 μs.
It was °.

Example 18 2-(2-fluoro-4-octoxy)phenyl-5-
(4-hedityl)phenylpyrimidine X1 = X2 = single bond) 35 weight, 4octyl-1-(4-hexylpenzyloxy)benzene (in compound C, Ra = n
-C6H17 +
-CaH17-)31 SCC matrix liquid crystal 8
The composition was prepared.

An SC" liquid crystal composition was prepared consisting of this base SC liquid 6 composition 70 weight i-4 and the compound 30 weight it of Example 12. This S00 liquid crystal composition exhibited an SC* phase at 51°C or lower, It exhibited a high-speed response of 40 double seconds at 35°C.

Example 19 Three pyrimidine components of B (R3-n-C6H1y -*R
4” n-CIoH210-# 28% by weight; R
, -n-C6H17+.

R4-n-C, Hl, O-, 28%; R
3=n-C3H1,-.

R4” n-C, 3H170-, 24 weight t%) and 2-
(2-fluoro-4-octoxy)phenyl-5-(4
A base SC liquid crystal composition C consisting of 20% by weight of -heptyl)phenylpyrimidine was prepared. This base SCg and crystal composition C exhibit an SC phase up to 67.5°C, and an S phase up to 71°C.
It showed A phase and N1 phase up to 80.5°C, and its melting point was 13°.

When a mg product consisting of 90% of this base SC liquid crystal composition C and Compound 10 of Example 15, which does not show a liquid crystal phase by itself, was prepared, it showed an SC" phase up to 52.5 degrees, and no crystallization was observed. There wasn't.

This "sc" liquid crystal composition has a power density of 1.1 nC/cIr at 25°C.
It showed spontaneous polarization of L2.

〔Effect of the invention〕

The compound of the present invention (13 is an SC* obtained by adding it as a chiral dopant to a base SC liquid crystal composition)
It induces larger spontaneous polarization in liquid crystal compositions than conventionally known ester-based ferroelectric compounds. Also, sc”
The OT ability is to make the helical pitch of the liquid crystal composition sufficiently large, and adjustment of the helical pitch is hardly necessary or is extremely easy.

As shown in the examples, the compound (11) of the present invention can be easily produced industrially, is colorless and has excellent chemical stability against water, light, heat, etc., and is particularly useful for medicinal purposes.

Historically, the S00 liquid crystal composition according to the present invention has an extremely high response speed of 100 microseconds or less, and is extremely useful as a light switching element for display.

Agent Patent Attorney Katsutoshi Takahashi

Claims (1)

[Claims] 1. General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R_1 represents an alkyl group having 1 to 16 carbon atoms, and R_2 represents an alkyl group having 2 to 16 carbon atoms. ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ are each independently ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Y represents -COO-, -OCO- or a single bond. l, m and n each independently represent 0 or 1, k represents an integer from 0 to 6, C^* and C^* ^* each independently represents an asymmetric carbon atom in the (S) or (R) configuration.) A compound represented by: 2. The compound according to claim 1, wherein m is 0 and n is 1. 3. The compound according to claim 1, wherein m is 1 and n is 0. 4. ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ Mathematical formulas , chemical formulas, tables, etc. ▼ is ▲ mathematical formulas, chemical formulas,
There are tables, etc. ▼ and ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼ is ▲ there are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲
The compound according to claim 1, which has a mathematical formula, a chemical formula, a table, etc. 5. The compound according to claim 1, wherein k is 0 or 1. 6. The compound according to claim 1, wherein R_2 is an alkyl group having 2 to 6 carbon atoms. 7. The absolute configurations in C^* and C^*^* are both (S
) configuration according to claim 1. 8. The compound according to claim 7, wherein the sum of l and k is 1. 9. A liquid crystal composition containing the compound according to claim 1. 10. The liquid crystal composition according to claim 9, which exhibits a chiral smectic C phase.