JPH0459746A - Carboxylic ester compound, liquid crystal compound and liquid crystal composition - Google Patents

Abstract

NEW MATERIAL:A carboxylic ester compound of formula I (R is 3-20C alkyl, 3-20C alkoxy, 3-20C halogenated alkyl; the ring A is group of formula II, III, IV, V, VI or VII). EXAMPLE:1'''-Trifluoromethylheptyl trans-4-[4'-(6''-n-decyloxy-2''-naphthoyloxy) phenyl]cyclohexanecarboxylate. USE:A liquid crystal compound. The compound gives display elements having characteristics such as a wide action temperature range, a large switching rate, a switch threshold voltage in a proper range and an extremely little consumption power. PREPARATION:For example, a compound of formula VIII is reacted with a compound of formula IX and further with a 6-alkoxynaphthalene-2-carboxylic acid to obtain the compound of formula I wherein the ring A is a group of formula III and R is alkoxy.

Description

[Detailed description of the invention] Oimidate Gogoso! The present invention relates to novel carboxylic acid ester compounds, liquid crystal compounds, and liquid crystal compositions. More specifically, the present invention relates to novel carboxylic acid ester compounds, liquid crystal compounds, and liquid crystal compositions used in display elements and the like.

TECHNICAL BACKGROUND OF THE INVENTION Many display devices such as office automation equipment that have been used in the past are driven in TN (twisted nematic) mode.

However, when this method is adopted, in order to change the displayed image, it is necessary to change the molecular position of the liquid crystal compound, which increases the driving time and also requires additional processing time to change the molecular position of the liquid crystal compound. There is a problem in that the voltage applied, that is, the power consumption also increases.

On the other hand, a switching element using a ferroelectric liquid crystal compound can function as a switching element simply by changing the alignment direction of the molecules of the liquid crystal compound, so that the switching time can be significantly shortened. Furthermore, since the product (psXE) of the spontaneous polarization (Ps) of the ferroelectric liquid crystal compound and the electric field strength (E) is the effective energy intensity for changing the orientation direction of molecules, power consumption is also extremely low. . Since such ferroelectric liquid crystal compounds have two stable states, or bistability, depending on the direction of the applied electric field, their switching threshold characteristics are also very good, making them useful as display devices for moving images. Particularly suitable for use.

When using such ferroelectric liquid crystal compounds in optical switching devices, etc., ferroelectric liquid crystal compounds must have an operating temperature range near or below room temperature, a wide operating temperature range, and a high switching speed. Many characteristics are required, such as being fast (fast) and having a switching threshold voltage within an appropriate range.

However, regarding conventionally known ferroelectric liquid crystal compounds, for example, R.B. Meyer et al.
, the paper [Journal de Physique (J, de
Phys, ) Volume 36, page L-69, 1975 Ko, Masaaki Taguchi, Takamasa Harada's paper [Proceedings of the 11th LCD Symposium 16
8, 1985], even though ferroelectric liquid crystal compounds generally have a narrow operating temperature and a wide operating temperature range, they do not have sufficient other properties and cannot be used as ferroelectric liquid crystal materials. Nothing that is practically satisfactory has been obtained.

OBJECTS OF THE INVENTION The present invention aims to provide novel carboxylic acid ester compounds.

Furthermore, the present invention particularly provides a liquid crystal that can be used to form a display device, etc., which has excellent characteristics such as a wide operating temperature range, a high switching speed, a switching threshold voltage within an appropriate range, and operation with extremely low power consumption. The present invention aims to provide compounds and liquid crystal compositions.

Summary of the Invention The carboxylic acid ester compound of the present invention has the following formula % formula % [] However, in formula [I], R has 3 to 20 carbon atoms.
Detailed Description of the Invention Next, the carboxylic acid of the present invention The ester compound will be specifically explained.

The carboxylic acid ester compound of the present invention has the following formula % formula % Represents a group selected from the group consisting of.

Further, the liquid crystal compound of the present invention is characterized by being represented by the above formula [I].

Furthermore, the liquid crystal composition of the present invention is characterized by containing a carboxylic acid ester compound represented by the above formula [I].

The present invention provides novel carboxylic acid ester compounds. By using this carboxylic acid ester compound as a liquid crystal compound, we can manufacture various devices with excellent properties such as a wide operating temperature range, high switching speed, extremely low power consumption, and stable contrast. I can do it.

... [I, however, the expression [! ], R has 3 to 20 carbon atoms
It is a type of group selected from the group consisting of an alkyl group having 3 to 2 o carbon atoms, an alkoxy group having 3 to 2 o carbon atoms, and a halogenated alkyl group having 3 to 20 carbon atoms.

In the above formula [E], when R is an alkyl group having 3 to 20 carbon atoms, such alkyl group may be in any form of linear, branched or alicyclic form. However, the molecules of carboxylic esters in which R is a linear alkyl group exhibit excellent liquid crystallinity because they have a rigid structure in which the molecules extend straight. Such a linear alkyl group is preferably an alkyl group having 6 to 20 carbon atoms, and specific examples of such a linear alkyl group include hexyl group, heptyl group, octyl group, Examples include decyl group, dodecyl group, tetradecyl group, hexadecyl group and octadecyl group.

In addition, when R is a halogenated alkyl group having 3 to 20 carbon atoms, examples of the halogenated alkyl group include:
Examples include groups in which at least a portion of the hydrogen atoms of the above-mentioned alkyl groups are substituted with halogen atoms such as F, CM, Br, and engineering.

Further, when R is an alkoxy group having 3 to 20 carbon atoms, examples of such an alkoxy group include an alkoxy group having an alkyl group as described above. Specific examples of such alkoxy groups include hexoxy, heptoxy, octyloxy, decyloxy, dodecyloxy, tetradecyloxy, heptadecyloxy, hexadecyloxy and octadecyloxy groups. be able to.

When using the carboxylic acid ester compound of the present invention as a liquid crystal compound, compounds in which R is an alkoxy group in the formula [Il] are highly useful.

Furthermore, in the above formula [I], Represents one type of group selected from the group consisting of.

Among these groups, when the carboxylic acid ester compound of the present invention is used as a liquid crystal compound, in consideration of liquid crystal properties, any of the groups represented by these is preferable. Therefore, specific examples of the carboxylic acid ester compound of the present invention represented by the above formula [J] include compounds represented by the following formulas [1] to [48].

(Margin below) ...[30] C.F.

...[361 ...[42] The carboxylic acid ester compound of the present invention can be produced by using a combination of known synthesis techniques.

For example, the above carboxylic acid ester compound can be synthesized according to the synthetic route shown below. In addition, in the example of the reaction route shown below, the case where R1 is an alkoxy group is made into an example, and the synthesis example of the carboxylic acid ester compound of this invention is demonstrated.

That is, for example, trans-4-(4°-benzyloxyphenyl)cyclohexanecarboxylic acid (i) and 1
- reacting with trifluoromethylheptyl alcohol (11) using 4-N,N-dimethylaminopyridine and methylene chloride as a solvent while dropping an esterifying agent such as N,N'-dicyclohexylcarbodiimide. Trans-4-(4'-benzyloxyphenyl)cyclohexanecarboxylic acid-1''-trifluoromethylheptyl ester (iii) is obtained.

trans-4-(4°-benzyloxyphenyl)cyclohexanecarboxylic acid 1”- obtained as above
) Lifluoromethylheptyl ester (iii) is added to a solvent such as tetrahydrofuran and reduced using hydrogen gas in the presence of a reduction catalyst such as palladium-carbon to obtain trans-4-(4'-hydroxyphenyl). Cyclohexanecarboxylic acid-1''-)lifluoromethylheptyl ester (iv) is obtained.

Then, using 4-N,N-dimethylaminopyridine and methylene chloride as a solvent, while dropping N,N'-dicyclohexanecarbodiimide, 6-alkoxynaphthalene-2-carboxylic acid (V) obtained in the above step was added. The carboxylic acid ester compound of the present invention can be obtained by reacting the obtained trans-4-(4°-hydroxyphenyl)cyclohexanecarboxylic acid-1″°-trifluoromethylhephthyl ester (1v).

Note that the above method is an example of a method for producing the carboxylic acid ester compound of the present invention, and the carboxylic acid ester compound of the present invention should not be interpreted to be limited by such a production method.

Among the carboxylic acid ester compounds according to the present invention obtained as described above, trans-4-[4°
An IH-NMR chart of -(6''-n-decyloxy-2'-naphthoyloxy)phenylcocyclohexanecarboxylic acid-1''-)lifluoromethylheptyl ester is shown in FIG.

In the above formula, the numbers 1 to 11 indicate hydrogen thicknesses, and these numbers correspond to the numbers assigned to the peaks in FIG.

In addition, 1,2,3.4-tetrahydro-6-(6°-n-hebutyloxy-2'-naphthoyloxy)naphthalene-2-carboxylic acid R-1''-)refluoro The second IH-NMR chart of methylheptyl
As shown in the figure.

In addition, in the above formula, the numbers 1-10 indicate hydrogen atoms, and these numbers correspond to the numbers assigned to the peaks in Figure 2.In the formula [1] obtained as above, The represented carboxylic acid ester compound can be used as a raw material for the synthesis of organic compounds, and can also be suitably used, for example, as a liquid crystal compound.

Among these carboxylic acid ester compounds,
As liquid crystal compounds, compounds represented by the following formulas [10], [30] and [39] exhibit excellent liquid crystal properties.

Table 1 shows the phase transition temperatures of the liquid crystal compounds [10], [30] and [39]. In the tables shown below, Cry represents a crystalline phase, SmC ratio represents a chiral smectic C phase, SmA represents a smectic A phase, and Iso represents an isotropic liquid.

Table 1 [10] [30] [39] 72'C 27°C 25°C 90°C 50°C 110°C 122°C As illustrated in Table 1, the liquid crystal compound of the present invention exhibits a smectic phase over a wide temperature range. There are many compounds.

Conventionally, when a liquid crystal compound is used alone, there are almost no known liquid crystal compounds that exhibit a smectic phase over a wide range of temperatures like this compound.

The liquid crystal compound of the present invention not only exhibits a smectic phase over a wide range of temperatures, but also an optical switching element manufactured using such a liquid crystal compound has excellent high-speed response.

Although the liquid crystal compound of the present invention can be used alone, it is preferable to mix it with other liquid crystal compounds and use it as a liquid crystal composition. For example, the liquid crystal compound of the present invention can be used as a main ingredient in a chiral smectic liquid crystal composition or as an auxiliary agent in a liquid crystal composition containing another compound exhibiting smectic A as a main ingredient.

In other words, a liquid crystal compound exhibiting ferroelectricity induces an optical switching phenomenon by applying a voltage, and by utilizing this phenomenon, a display device with good responsiveness can be manufactured (for example, 56-107216, JP-A-59-118744, Japanese Patent Application No. 2-1166392).

Ferroelectric liquid crystal compounds that can be used in such display devices include chiral smectic C phase, chiral smectic F phase, chiral smectic C phase, chiral smectic H phase, chiral smectic I phase, chiral smectic J phase, or chiral smectic phase. A compound that exhibits either phase. However, display elements using such liquid crystal compounds other than the chiral smectic C phase (Sm C's phase) generally have a high (slow) response speed;
It was believed that driving by chiral smectic C phase is practically advantageous.

However, the method of driving a display element in the smectic A phase as already proposed by the present inventors (Japanese Patent Application No. 62-1
57808), the ferroelectric liquid crystal compound of the present invention can be used not only in the chiral smectic C phase but also in the smectic A phase. Therefore, by blending the liquid crystal compound of the present invention with other liquid crystal compounds, it is possible to obtain a liquid crystal composition that has a wide range of liquid crystal temperatures and further has faster electro-optical compatibility.

When producing a liquid crystal composition using the liquid crystal compound of the present invention, this liquid crystal compound can be used as a main agent or as an auxiliary agent, as described above.

In the liquid crystal composition containing the liquid crystal compound of the present invention, the content of the liquid crystal compound represented by the above formula [I] is as follows:
It can be appropriately set in consideration of the characteristics of the liquid crystal compound used, the viscosity of the composition, the operating temperature, the intended use, etc. In particular, the liquid crystal compound is usually used in an amount ranging from 1 to 99% by weight, preferably from 5 to 75% by weight, based on the total weight of the liquid crystal substances in the liquid crystal composition.

Further, one or more types of liquid crystal compounds of the present invention may be blended in the liquid crystal composition.

In such a liquid crystal composition, examples of compounds exhibiting a chiral smectic C phase that can be blended with the liquid crystal compound represented by the above formula [l] include (+)
-4'-(2''-methylbutyloxy)phenyl-6
-Octyloxynaphthalene-2-carboxylic acid ester, 4'-decyloxyphenyl-6-((+)-2°'-
(methylbutyloxy)naphthalene-2-carboxylic acid ester.

Further, as an example of a liquid crystal compound that can constitute a liquid crystal composition by blending a carboxylic acid ester compound represented by the above formula [E] with a compound other than the above-mentioned compound exhibiting the chiral smectic C phase, are Schiff base-based liquid crystal compounds such as CH30◎CH=N@caHQ (C6H]3)O(wing CH=N@CN, azoxy-based liquid crystal compounds such as (C4H9)0goC00GCell 13 (C71f)
ts )0-◎coo◎benzoic acid ester liquid crystal compounds such as Cll, (C5H11)<E)COO◎CN (c5++1.) (E)coo((double0-C51111
cyclohexylcarboxylic acid ester liquid crystal compounds such as 1, diphenyl liquid crystal compounds such as (C5H,,)-@-begCN, terphenol liquid crystal compounds such as, cyclohexyl liquid crystal compounds such as In addition to nematic liquid crystal compounds represented by pyrimidine liquid crystal compounds such as and, cholesteric liquid crystal compounds such as cholesterin hydrochloride, cholesterin nonanoate, and cholesterin oleate, as well as known smectic liquid crystal compounds. can be mentioned.

In addition, when forming, for example, a display element using the liquid crystal compound according to the present invention, in addition to the above-mentioned liquid crystal compound, for example, a conductivity imparting agent and a life-enhancing agent may be used together with ordinary liquid crystal compounds. Additives may be added.

A liquid crystal composition can be prepared by mixing the liquid crystal compound of the present invention, the liquid crystal compound as described above, and other additives by a conventional method.

A liquid crystal element can be prepared using such a liquid crystal composition.

FIG. 3 shows an example of a cross section of a liquid crystal element using the above liquid crystal composition.

As shown in Figure 3, this liquid crystal element basically consists of two
A transparent substrate (hereinafter also referred to as a substrate) 1a.

1b and a gap 3 defined by the two substrates 1a and lb, and a liquid crystal composition 4 filled in the gap 3 between the cells.

At least one of the substrates 1a, lb must be transparent, and usually glass or transparent plastic such as polycarbonate is used as the substrate.

At least one of the substrates 1a and 1b is usually coated with indium oxide on at least the surface facing the liquid crystal composition (the inner surface of the substrate).
Electrodes 5a and 5b made of tin or the like are provided. Further, as the substrate, a transparent electrode substrate in which a transparent electrode is integrally formed on the substrate as described above can also be used.

Furthermore, alignment control films 6a and 6b are provided on at least one surface of the substrate as described above that is in contact with the liquid crystal composition. Although it is sufficient that the orientation control film 1 is provided on one substrate, it is preferable that the orientation control film is provided on both substrates. FIG. 3 shows an embodiment in which two alignment control films are provided, one for each substrate, and these alignment control films are indicated by 6a and 6b. Such alignment control films include, for example, polyimide, polyvinyl alcohol, polyamideimide, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, siloxane polyimide, cellulose resin, melamine resin, Yuria resin, acrylic. Polymer films formed from polymer compounds such as resins or conductive polymers: cyclized rubber photoresists,
Films formed from cured electron beam photoresists such as phenol novolak photoresists, polymethyl methacrylate, and epoxidized 1,4-polybutadiene:
and,Sin,Sin,,Ge01A Q20. ,Y
This is a deposited film formed from inorganic compounds such as 2O1, ZrO2, MgF2, and CeF. As the orientation control film, a polyamide film or an obliquely deposited SiO3 film is particularly suitable.
Alternatively, a vapor-deposited film of an inorganic compound such as a GeO film is preferable. One such alignment control film may be provided on the surface facing the liquid crystal of either one of the substrates, but it is preferable to provide a total of two films, one on the surface of each substrate facing the liquid crystal composition. Preferably.

This type of self-control @ film has a surface that is enveloped by the liquid crystal of the substrate.
A method of applying the above-mentioned resin by, for example, a spin code method, a method of applying heat treatment after such application,
Various methods are used depending on the material used, such as pasting a resin film, applying a photosensitive resin and then curing it by irradiating it with energy rays, and vapor-depositing an inorganic material. can be formed.

Furthermore, this orientation control film is usually subjected to an orientation treatment. Here, the alignment treatment refers to a treatment for aligning liquid crystal molecules in a predetermined direction. For example, when polyimide is used, it is performed by rubbing the polyimide in one direction with a cloth, etc. This polyimide can be subjected to orientation treatment by a rubbing method.

The thickness of such an alignment control film is usually o, oos ~ 0.2
5 μm, preferably within the range of 0.01 to 0.15 μm.

When an alignment control film is disposed on each substrate, the alignment control film as described above may be disposed so that the direction of the liquid crystal compound regulated by the alignment control film is constant. In particular, the alignment direction of the liquid crystal compound oriented by the regulating force of one alignment control film and the alignment direction of the liquid crystal compound oriented by the regulating force of the other alignment control film are substantially parallel, and the alignment direction is It is preferable to arrange the two alignment control films so that they are substantially opposite to each other. By arranging the alignment control film in this manner, the initial alignment of the liquid crystal composition injected into the cell is improved, and a liquid crystal element with excellent contrast and the like can be obtained.

The cell filled with the liquid crystal composition includes two substrates 1a and lb on which alignment control films 6a and 6b are formed as described above.
A gap 3 is formed which is filled with liquid crystal material.

Such a gap 3 can be formed, for example, by arranging the substrates 1a and 1b with spacers 7 interposed therebetween. By arranging the spacer 7 in this way, it is possible to secure the gap 3 for filling the liquid crystal composition, and it is also possible to prevent the liquid crystal composition from leaking. Note that space #3 can be formed using a spacer that forms a side wall as described above, and also particles having a predetermined particle diameter (internal spacer) in the liquid crystal composition.
It can also be formed by blending.

The width of the gap formed in this way is usually 1.5 to 7
μm1 is preferably within the range of 1.8 to 5 μm.

In such a liquid crystal element, various thin films such as a photoconductive film, a light blocking film, and a light reflecting film may be further provided.

In such a liquid crystal element, the cell gap 3 as described above is filled with a liquid crystal composition containing the carboxylic acid ester compound of the present invention in an oriented state.

At least one deflection plate is disposed outside the cell thus formed. In Figure 3,
The deflection plates are shown at 8a, 8b. This deflection plate 8a
, 8b are arranged so that their deflection surfaces form an angle of usually 70 to 110 degrees, preferably 90 degrees. Furthermore, a liquid crystal element 10 (in which a liquid crystal compound is filled and initially aligned) is placed between these two polarizing plates.
(liquid crystal composition filled in the gaps between cells) to determine the positional relationship of the champion so that the light beam transmitted through the deflection plate 8a, the liquid crystal element 10, and the deflection plate 8b is in the brightest state or the darkest state. is preferred.

The liquid crystal element as described above can be driven, for example, by the following method.

The first method is to interpose a thin film cell filled with an oriented liquid crystal compound between two polarizing plates, apply an external electric field to this thin film cell, and change the orientation vector of the ferroelectric liquid crystal compound. , is a method of displaying using the polarization properties of two polarizing plates and the birefringence of a ferroelectric liquid crystal compound.

When a chiral smectic phase is formed in such a thin film cell, the liquid crystal compound exhibits bistability. Utilizing this property, it is possible to reverse the electric field and transition the liquid crystal compound from one stable state to another. Optical switching can then be performed using these two stable states.

Among the liquid crystal compounds of the present invention, ferroelectric liquid crystal compounds exhibiting a chiral smectic phase have spontaneous polarization.
- When a variable voltage is applied, there is a memory effect even after the electric field is erased. Therefore, by utilizing this memory effect, it is possible to maintain a constant state in which voltage continues to be applied to the thin film cell.

Therefore, a display device having such a thin film cell can reduce power consumption. Furthermore, in this case the contrast of the display device is stable and yet very sharp.

Furthermore, in a switching element using a chiral smectic liquid crystal compound, switching is possible simply by changing the orientation direction of the molecules, and since the primary term of electric field strength acts on the drive, low voltage drive is possible.

Furthermore, if this switching element is used, a high-speed response of several tens of microseconds or less can be realized, so the scanning time of each element can be significantly shortened, making it possible to manufacture a large-screen display with many scanning lines.

Furthermore, optical switching can be performed using an antiferroelectric liquid crystal composition containing this compound.

Further, even in the smectic A phase of the liquid crystal compound of the present invention, which does not have bistability, when an electric field is applied, the molecules are induced to tilt, so optical switching can be performed using this property. Furthermore, since the liquid crystal compound of the present invention exhibits two or more stable states even in a liquid crystal phase with low symmetry, optical switching can be performed in the same manner as in the case of the smectic A phase.

A second display method using the liquid crystal compound of the present invention is a method of mixing the liquid crystal compound of the present invention and a dichroic dye and utilizing the dichroism of the dye. This is a method of displaying by changing the wavelength of light absorbed by the dye by changing the orientation direction of the compound. The dye used in this case is usually a dichroic dye, and examples of such dichroic dyes include azo dyes, naph)4non dyes, cyanine dyes, and anthraquinone dyes. .

In addition, in a liquid crystal element using a liquid crystal composition containing the liquid crystal compound of the present invention, various commonly used display methods can be employed in addition to the display methods described above. That is, a liquid crystal element using a liquid crystal composition containing the liquid crystal compound of the present invention can be used for electric address display such as static drive, simple matrix drive, and composite matrix drive, optical address display, thermal address display, electron beam address display, etc. It can be driven depending on the driving method.

Such a liquid crystal element can be used as various devices such as a White Tiller type color display device, a cholesteric nematic phase change type display device, and a device for preventing the occurrence of reverse domain in a TN type cell.

Furthermore, the liquid crystal element as described above can be used in a memory type liquid crystal display element such as a thermal writing type display element or a laser writing type display element.

Furthermore, elements using liquid crystal compounds with ferroelectric properties are
In addition to the above-mentioned uses, it can be preferably used in optical switching elements such as optical shutters or liquid crystal printers, and liquid crystal elements such as piezoelectric elements and pyroelectric elements.

Effects of the Invention The present invention provides a novel carboxylic acid ester compound.

This novel carboxylic acid ester compound is optically active and has a specific structure in which ring structures including naphthalene ring structures are combined, and this structure forms a rigid structure. , exhibits a smectic phase in a wide temperature range around room temperature, and can be preferably used as a ferroelectric liquid crystal compound.

By blending the same type and/or other types of liquid crystal compounds with this liquid crystal compound, it is possible to lower the operating temperature of the liquid crystal phase without impairing the ferroelectricity of this liquid crystal compound. The temperature range can be expanded.

Therefore, by using this liquid crystal compound or a liquid crystal composition containing this liquid crystal compound, it is possible to obtain a display element or the like that has high-speed response over a wide temperature range.

Further, this liquid crystal compound or a liquid crystal composition containing this liquid crystal compound can be preferably used as an antiferroelectric liquid crystal compound in a wide temperature range around room temperature.

Furthermore, the scanning time of liquid crystal displays manufactured using such devices is significantly reduced.

Further, since the liquid crystal compound of the present invention has spontaneous polarization, by filling a thin film cell with the liquid crystal compound, a device having a memory effect even after erasing the electric field can be obtained.

In such a device, power consumption can be reduced and stable contrast can be obtained. Low voltage drive is also possible. Since such a device utilizes the smectic phase of a carboxylic acid ester compound, it is preferably used as an optical switching element used in a wide temperature range.

Next, examples of the present invention will be shown, but the present invention is not limited to these examples. Further, the symbols R and S used below mean R-form and oct-form.

Example 1 trans-4-[4°-(6°'-n-decyloxy-
Synthesis of 2°°-naphthoyloxy)phenylcocyclohexanecarboxylic acid-1''-)lifluoromethylheptyl ester 1st step trans-4-(4°-hydroxyphenyl)cyclol
＼2.20 g (10 mmol) of xanecarboxylic acid, 6.84 g (40 mmol) of benzyl bromide, 5 potassium carbonate
．． A mixture of 53 g (40 mmol) and 50 ml of dimethylformamide was stirred at 120° C. for 4 hours.

The mixture was further stirred at room temperature for 4 hours.

Trans-4-(4'-benzoyloxyphenyl)cyclohexanecarboxylic acid benzyl ester, a white solid, is obtained by adding the reaction mixture into 450 ml of water, filtering the resulting viscous material and washing with hexane.2. 54
g (6.4 mmol) was obtained.

2.54 g (6.4 mmol) of trans-4-(4°-benzyloxyphenyl)cyclohexanecarboxylic acid benzyl ester obtained in the first step, 0.86 g (13 mmol) of 85% potassium hydroxide aqueous solution ) and 30 ml of ethanol. A mixture of 30 ml of water was stirred at 120° C. for 9 hours.

The reaction mixture was added to 200 ml of water and the system was made acidic by dropwise addition of hydrochloric acid, yielding a white solid.

By filtering this, white solid trans-
1.68 g (5.4 mmol) of 4-(4°-benzyloxyphenyl)cyclohexanecarboxylic acid were obtained.

3rd stage 1.68 g of trans-4-(4″-benzyloxyphenyl)cyclohexanecarboxylic acid obtained in the 2nd stage (
5.4 mmol), R-1-)lifluoromethylheptyl alcohol 0.994 g (5.4 mmol), 4
-N,N-dimethylaminopyridine 0.12g (1 mmol) and methylene chloride 20ml were added
10.8 ml of a methylene chloride solution containing 1.11 g (5.4 mmol) of '-dicyclohexylcarbodiimide was added dropwise with stirring over 1 hour.

The mixture was further reacted at room temperature for 10 hours.

The reaction mixture was filtered and the resulting filtrate was concentrated.

By separating the concentrate using column chromatography, Tolan X-4-(4'-/
(ndyloxyphenyl)cyclohexanecarboxylic acid R
-1”-trifluoromethylheptyl ester 2.27
g (4, furimimole) was obtained.

4th step trans-4-(4'-benzyloxyphenyl)cyclohexanecarboxylic acid R-1''- obtained in the 3rd step
2.27 g (4° furimmol) of refluoromethylheptyl ester, 1.6 g of 5% palladium-carbon catalyst.

Hydrogen gas was bubbled into a mixture of 57 ml of tetrahydrofuran at room temperature for 6.5 hours while stirring.

Next, the reaction mixture was filtered using Celite, which is a filter aid, and the resulting filtrate was further concentrated.

By separating the concentrate using column chromatography, trans-4 (4'-hydroxyphenyl), cyclohexanecarboxylic acid R-1, which is a colorless viscous substance, was obtained.
-) Lifluoromethylheptyl ester 1°90 g
(4, furomimol) was obtained.

5th step 0.386 g (1 mmol) of trans-4-(4-hydroxyphenyl)cyclohexylcarboxylic acid R-1''-trifluoromethylheptyl ester obtained in the 4th step 6-〇-decyloxynaphthalene 2-carboxylic acid 0
．． 328 g (1 mmol), 0.21 g (1 mmol) of N,N'-dicyclohexylcarbodiimide in a mixture of 0.012 g (0.1 mmol) of 4-N,N-dimethylaminopyridine and 10 ml of methylene chloride. 2 ml of a methylene chloride solution containing the above was added dropwise over 1 hour while stirring at room temperature.

The reaction was further continued at room temperature for 8 hours.

The reaction mixture was filtered and the resulting filtrate was concentrated.

The concentrate was separated using column chromatography to obtain 0.58 g of a white solid.

When the FD-mass spectrum of this white solid was measured, the value of M/e was 696.

FIG. 1 shows a chart of the IH-NMR spectrum of this compound.

The compound obtained from these analysis results is the target trans-4-[4°-(6”-n-decyloxy2′°-
naphthoyloxy)phenylcocyclohexylcarboxylic acid R-1'°-trifluoromethylheptyl ester (
It was identified as Exemplified Compound [18]).

Example 2 1,2.3.4-tetrahydro-6-(6°-〇-hebutyloxy2°-naphthoyloxy)naphthalene-2-
Synthesis of carboxylic acid R-1''-trifluoromethylheptyl ester 1st step 3.76 g (20 mmol) of 6-hydroxy-2-naphthoic acid, 5.38 g (30 mmol) of 1-bromohebutane, 85% purity water A mixture of 2.64 g (40 mmol) of potassium oxide, 0.11 g (0.7 mmol) of sodium iodide, 40 ml of ethanol and 5 ml of water was reacted under nitrogen atmosphere at reflux temperature for 10 hours. 20 ml of an aqueous potassium hydroxide solution was added, and the mixture was further reacted at the same temperature for 2 hours. After the reaction mixture was cooled to room temperature, 80 ml of water was added and acidified with 20% hydrochloric acid, and the precipitated solid was isolated by filtration.

The filtrate was washed with water, dried, and recrystallized with 10 times the weight of ethanol to obtain 4.26 g (14°9) of 6-n-heptyloxy-2-naphthoic acid as a white solid.
mmol) was obtained.

Second stage A mixture of 2.86 g (10 mmol) of 6-n-hebutyloxy-2-naphthoic acid obtained in the first stage and 75 ml of 1,2-jethoxyethane was heated to 120°C and stirred under a nitrogen atmosphere. 3 g (130 millipram atoms) of sodium metal was added to the mixture, and the mixture was further heated to reflux temperature.

To this reaction mixture was added 13.55% of 1so-amyl alcohol.
g (154 mmol) was added dropwise over 1 hour, and the reaction was continued under reflux for an additional 9 hours. After cooling to room temperature, remaining metallic sodium was decomposed by adding ethanol, and the reaction mixture was made acidic using 20% hydrochloric acid. After adding 100 ml of water to the reaction mixture, the organic phase was separated and further washed with water.

The organic phase was concentrated under reduced pressure to obtain 3.54 g of solid.

By recrystallizing this solid using 4 times the weight of hexane, 1, 2.3.4-tetrahydro-6-n-heptyloxy-2-naphthoic acid 2, which is a white solid, is obtained.
2 g (7.6 mmol) were obtained.

3rd stage 1, 2, 3, 4-tetrahydro- obtained in the 2nd stage
2.2 g of 6-n-hebutyloxy-2-naphthoic acid (7
, 6 mmol), 50 ml of acetic acid and 15.5 g of 47% hydrobromic acid were reacted at reflux temperature for 10 hours.

By concentrating under reduced pressure, solid 1, 2.3
1.46 g of 4-tetrahydro-6-hydroxy-2-naphthoic acid was obtained. The product was subjected to the next reaction without any particular purification.

4th stage 1, 2, 3, 4-tetrahydro- obtained in the 3rd stage
6-hydroxy-2-naphthoic acid (crude product) 1.46
g, benzyl bromide 5.47 g (32 mmol),
4.42 g (32 mmol) of potassium carbonate and N,N
-A mixture of 40 ml of dimethylformamide was reacted at 120°C for 10 hours. After cooling to room temperature, 200 ml of water was added, acidified with 20% hydrochloric acid, and then diluted with toluene 1, 2.
3.4-tetrahydro-6-benzyloxy-2-naphthoic acid benzyl ester and 1.2.3.4-tetrahydro-6-benzyloxy-2-naphthoic acid were extracted.

The extract was concentrated under reduced pressure to obtain 2.71 g of concentrate.

30 g of hexane was added to this concentrate, shaken, and left to stand to remove the hexane phase. The remaining organic phase was concentrated under reduced pressure to obtain 2.40 g of concentrate. This was subjected to the next reaction without further purification.

5th stage 2.40 g of crude product obtained in the 4th stage, purity 85
A mixture of 1.32 g (20 mmol) of % potassium hydroxide, 50 g of ethanol and 5 g of water was reacted at reflux temperature for 13 hours. After cooling the reaction mixture to room temperature, add 200ml of water.
1 and acidified with 20% hydrochloric acid, the precipitated pale yellow solid was filtered off and washed with water and hexane. After drying, 1.20 g (4.3 mmol) of 1.2.3.4-tetrahydro-6-benzyloxy-2-naphthoic acid was obtained.

6th stage 0.239 g of 1, Z, 3,4-tetrahydro-6-benzyloxy-2-naphthoic acid obtained in the 5th stage
(0,85 mmol), R-1-)rifluoromethylheptatool 0,1-56 g (0,85 mmol)
, 4-N, N-dimethylaminopyridine 0.012
g (0.1 mmol) and 2 ml of methylene chloride solution containing 0.21 g (1 mmol) of N,N'-dicyclohexylcarbodiimide in a mixture of 20 ml of methylene chloride.
1 was added dropwise over 1 hour at room temperature with stirring. The mixture was further reacted at room temperature for 6 hours.

The reaction mixture was filtered and the resulting filtrate was concentrated.

By separating the concentrate using column chromatography, 1,2.3.4-tetrahydro-6-benzyloxy-naphthalene-2-carboxylic acid R-1'-)lifluoromethylheptyl, which is a pale yellow liquid, was obtained. ester 0
, 34 g (0, furomillimoles) were obtained.

7th step 1, 2.3.4-tetrahydro- obtained in the 6th step
6-benzyloxy-naphthalene-2-carboxylic acid R-
1°-trifluoromethylheptyl ester 0.31
g (0.69 mmol), 5% palladium/carbon 0.
Hydrogen was blown into a mixture of 3 g and 30 ml of tetrahydrofuran at room temperature and under normal pressure for 8 hours while stirring. The reaction mixture is filtered using Celite, which is a filter aid, and the resulting filtrate is concentrated to obtain a pale yellow liquid, 1, 2.3.
0.25 g (0.69 mmol) of 4-tetrahydro-6-hydroxy-naphthalene 2-carboxylic acid R-1°-trifluoromethylheptyl ester was obtained.

8th stage 1, 2.3.4-tetrahydro- obtained in the 7th stage
6-hydroxy-naphthalene-2-carboxylic acid R-1'
-1-Lifluoromethyl-heptyl ester 0.25g
(0.69 mmol), 0.20 g (0.6
9 mmol), 4N,N-dimethylaminopyridine 0.
012 g (0.1 mmol) and methylene chloride 2
1.4 ml of a methylene chloride solution containing 0.14 g (0.69 mmol) of N,N'-dicyclohexylcarbodiimide was added dropwise to 0 ml of the mixture at room temperature over 30 minutes with stirring. The mixture was further reacted at room temperature for 3 hours.

The reaction mixture was filtered and the resulting filtrate was condensed.

The concentrate was separated using column chromatography to obtain 0.32 g of a colorless semi-solid.

The value of the FD-mass spectrum of this semi-solid is M/e=
It was 626.

FIG. 2 shows a chart of the LH-NMR spectrum of this compound.

From these analysis results, this compound has the following properties:
2.3.4-Tetrahydro-6-(6°-n-hebutyloxy-2′-naphthoyloxy)-naphthalene-2-
It was identified as carboxylic acid R-1'-trifluoromethylheptyl ester (exemplified compound [30]).

Example 3 Synthesis of 4°-(6°゛-detruoxy-2pernaphthoyloxy)biphenyl-4-carboxylic acid-1′°°-trifluoromethylheptyl ester First step 4′-hydroxybiphenyl-4-carvone acid 6.42
g (30 mmol), benzyl bromide 20.52 g (12
0 mmol), potassium carbonate 16.58 g (120
A mixture of 40 ml of dimethylformamide and 40 ml of dimethylformamide was stirred at 120° C. for 2.5 hours.

The mixture was further stirred at room temperature for 4.5 hours.

The reaction mixture was added to 500 ml of water and filtered to obtain 4°-benzyloxybiphenyl-, a white solid.
4-carboxylic acid benzyl ester was obtained.

2nd stage 4-benzyloxybiphenyl-4 obtained in the 1st stage
-Carboxylic acid benzyl ester 11.82 g (30 mmol), 85% potassium hydroxide aqueous solution 3°96 g (60 mmol)
A mixture of 30 ml of ethanol and 30 ml of water was heated under reflux for 4 hours.

The reaction mixture was poured into 400 ml of water, and hydrochloric acid was added thereto to make the system acidic, yielding a white solid. By filtering this, 7.95 g of 4'-benzyloxybiphenyl-4-carboxylic acid (
26.2 mmol) was obtained.

3rd stage 4-benzyloxybiphenyl-4 obtained in the 2nd stage
-carboxylic acid 1.50 g (5 mmol), R-1-)lifluoromethylheptyl alcohol 0.92 g (5 mmol), 4-N, N-dimethylaminopyridine 0.
1 of N,N'-dicyclohexylcarbodiimide in a mixture of 122 g (1 mmol) and 30 ml of methylene chloride.
．． 10 ml of methylene chloride solution containing 0.3 g (5 mmol)
1 was added dropwise over 3 hours while stirring.

The mixture was further reacted at room temperature for 4 hours.

The reaction mixture was filtered and the resulting filtrate was concentrated.

By separating the concentrate using column chromatography, 1.17 g (2.5 mmol) of 4°-benzyloxybiphenyl-4-carboxylic acid R-1''-)lifluoromethylheptyl ester, which is a colorless liquid, was obtained. Obtained.

4th stage 4'-benzyloxybiphenyl- obtained in the 3rd stage
Hydrogen gas was added to a mixture of 1.15 g (2.44 mmol) of 4-carboxylic acid R-1''-)rifluoromethylheptyl ester, 0.9 g of 5% palladium-carbon catalyst and 50 ml of tetrahydrofuran at room temperature with stirring. was infused for 6 hours.

Next, the reaction mixture was filtered using a filter aid, chloride, and the resulting filtrate was concentrated.

The concentrate was subjected to column chromatography to obtain 4°-hydroxybiphenyl-4-carboxylic acid R-, which is a colorless liquid.
1”-) Lifluoromethylheptyl ester 0°92
g (2.44 mmol) was obtained.

5th step 4'-Hydroxybiphenyl-4- obtained in the 4th step
Carboxylic acid R-1''-trifluoromethylheptyl ester 0.38 g (1 mmol), 6-decyloxynaphthalene-2-carboxylic acid 0.328 g (1 mmol),
4-N, N-dimethylaminopyridine 0.012 g
(0.1 mmol) and 20 ml of methylene chloride, N,N'-dicyclohexylcarbodiimide 0
．． 2 ml of methylene chloride solution containing 21 g (1 mmol)
1 was added dropwise over 1 hour while stirring at room temperature.

The reaction was further continued at room temperature for 8 hours.

The reaction mixture was filtered and the resulting filtrate was concentrated.

The concentrate was separated using column chromatography to obtain 0.03 g of a white solid.

When the FD-mass spectrum of this white solid was measured, the value of M/e was 690.

As a result of analysis of this white solid, it was found that the obtained compound was the desired 4°-(6"-n-decyloxy-2"
-naphthoyloxy)biphenyl-4-carboxylic acid R-
It was identified as 1''-)rifluoromethylheptyl ester.

[Brief explanation of drawings]

Figure 1 is a chart of the IH-NMR spectrum of trans-4-[4°-6''-n-decyloxy-2''-naphthoyloxy)phenylcocyclohexanecarboxylic acid-1°''-trifluoromethylheptyl ester. be. Figure 2 shows 1.2.3.4-tetrahydro-6-(6°
FIG. 3 is a chart of the IH-NMR spectrum of -n-hebutyloxy-2°-naphthoyloxy)naphthalene di-2-carboxylic acid R-1''-)rifluoromethylheptyl. FIG. 3 shows that the liquid crystal composition of the present invention It is a sectional view showing an example of a liquid crystal element used. la, lb...transparent substrate (substrate), 2... cell,
3... Gap, 4... Liquid crystal composition, 5a, 5b...
・Electrode, 6a, 6b... Orientation control film, 7... Spacer, 8a, 8b... Bending plate, 10... Contents of liquid crystal element correction

Claims (3)

[Claims] (1) A carboxylic acid ester compound characterized by being represented by the following formula [I]; ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ... [I] [However, in the formula [I], R is Number of carbon atoms: 3~
It is a type of group selected from the group consisting of 20 alkyl groups, alkoxy groups having 3 to 20 carbon atoms, and halogenated alkyl groups having 3 to 20 carbon atoms. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Represents a group selected from the group consisting of]. (2) Liquid crystal compound characterized by being represented by the following formula [I]; ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ... [I] [However, in the formula [I], R is a carbon atom Number 3~
It is a type of group selected from the group consisting of 20 alkyl groups, alkoxy groups having 3 to 20 carbon atoms, and halogenated alkyl groups having 3 to 20 carbon atoms. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Represents a group selected from the group consisting of]. (3) A liquid crystal composition characterized by containing a carboxylic acid ester compound represented by the following formula [I]; ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ...[I] ], R has 3 to 3 carbon atoms.
It is a type of group selected from the group consisting of 20 alkyl groups, alkoxy groups having 3 to 20 carbon atoms, and halogenated alkyl groups having 3 to 20 carbon atoms. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Represents a group selected from the group consisting of].