JP2009234973A - Method for purifying discotic liquid crystallin compound - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for purifying a discotic liquid crystallin compound which has a high yield, is inexpensive, has high productivity, has reduced solid waste and is suited for mass production. <P>SOLUTION: The method for purifying a discotic liquid crystallin compound by removing impurities from a discotic liquid crystallin compound solution containing a synthesized discotic liquid crystallin compound includes bringing the above discotic liquid crystallin compound solution into contact with a clay mineral as an adsorbent. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for purifying a discotic liquid crystal compound, and more specifically, a raw material for a functional material such as an optically anisotropic material such as a retardation film or a hole injecting and transporting material in an organic electroluminescence (EL) device. The present invention relates to a method for purifying a discotic liquid crystal compound that can be used as a liquid crystal compound.

  In recent years, liquid crystal display elements have been widely used in word processors, personal computers, televisions, and the like, and industrial activities such as materials and devices related thereto have been actively conducted. A lot of compounds have been developed for active research and development of liquid crystal compounds that are the basis of liquid crystal display materials. These compounds are considered to be used not only for display elements but also for development of various applications. In addition to the rod-shaped liquid crystal compounds that have been well known and used in the past, disc-shaped liquid crystal compounds, so-called discotic liquid crystal compounds, have recently attracted attention.

  A typical example of the discotic liquid crystal compound is C.I. Destrade et al., Mol. Cryst. Liq. Cryst. 71, 111 (1981), for example, benzene derivatives, triphenylene derivatives, truxene derivatives, phthalocyanine derivatives, and B.I. Kohne et al., Angew. Chem. 96, p. 70 (1984), cyclohexane derivatives, J. Am. M.M. Lehn et al. Chem. Soc. Chem. Commun. , 1794 (1985) and J. Zhang, J. et al. S. A study report by Moore et al. Am. Chem. Soc. 116, 2655 (1994), various macrocyclene derivatives, C.I. Destrade et al. Phsique, 40, 4, C3-17 (1979) and C.I. Vauchier et al., Mol. Cryst. Liq. Cryst. 66, page 103 (1981), JP-A-7-306317.

On the other hand, in a method for producing a discotic compound useful as a discotic liquid crystal compound by esterification from a central precursor having a phenolic hydroxy group and a side chain precursor having a carboxylic acid, There are known a method of converting a certain carboxylic acid with an acid chloride, and a method of performing esterification by a reaction between a mixed acid anhydride derivative which is a side chain portion precursor and a central portion precursor having a phenolic hydroxy group. For example, C.I. Vauchier et al. [Mol. Cryst. Liq. Cryst. 66, 103 (1981)] and T.W. W. A research report by Warmerdam et al. [Liquid Crystals 3, 1087 (1988)], JP-A-9-95467, and the like. However, in the methods disclosed in these, the performance of the obtained discotic liquid crystal compound as an optically anisotropic material is not always sufficient, and even if re-purification by crystallization of the compound is performed, The purification method by column chromatography was practically very difficult to adopt from the viewpoint of mass production and production productivity. As a method for solving these problems, Patent Document 1 (Japanese Patent Laid-Open No. 2003-113141) uses an adsorbent such as silica gel or a synthetic adsorbent (main components MgO, Al ₂ O ₃ , SiO ₂ ). And a method for producing a high-performance discotic liquid crystal compound is described. However, in this method, a discotic liquid crystal compound solution obtained by reacting a central portion precursor that can be a central portion of a discotic liquid crystal compound with a side chain portion precursor that can be a side chain portion and then washing with water is adsorbent. That requires contact with water to dehydrate water from the organic layer in advance with anhydrous magnesium sulfate, etc., requires multiple adsorption processes, complicates the production process, and There is a problem that it is necessary to use an adsorbent and a large amount of waste is generated.
JP 2003-113141 A

  Accordingly, an object of the present invention is to provide a method for purifying a discotic liquid crystal compound that is suitable for mass production with high yield, low cost, high productivity, and low solid waste.

  As a result of intensive studies, the present inventors have found that the above problem can be solved by the following purification method. That is, the present inventors have found that the incorporation of a trace amount of impurities, which is overlooked by normal detection means, greatly affects the performance as a discotic liquid crystal compound, and has completed the present invention. That is, the present invention is as follows.

1. A method for purifying a discotic liquid crystal compound that removes impurities from a discotic liquid crystal compound solution containing a synthesized discotic liquid crystal compound, the method comprising contacting a clay mineral as an adsorbent with the discotic liquid crystal compound solution A method for purifying discotic liquid crystal compounds.
2. 2. The synthesized crystal of a discotic liquid crystal compound is dissolved in an organic solvent to obtain a discotic liquid crystal compound solution, and a clay mineral as an adsorbent is contacted with the discotic liquid crystal compound solution. A method for purifying discotic liquid crystal compounds.
3. A clay mineral as an adsorbent is brought into contact with a discotic liquid crystal compound solution obtained by reacting a central part precursor that can be a central part of a discotic liquid crystal compound with a side chain part precursor that can be a side chain part. 2. The method for purifying a discotic liquid crystal compound as described in 1 above.
4). It is obtained by reacting a central part precursor having a phenolic hydroxyl group that can be a central part of a discotic liquid crystal compound with a side chain part precursor having a carboxylic acid group that can be a side chain part in the form of a mixed acid anhydride derivative. 4. The method for purifying a discotic liquid crystal compound as described in 3 above, wherein a clay mineral as an adsorbent is brought into contact with the discotic liquid crystal compound solution.
5. 5. The discotic liquid crystal as described in any one of 1 to 4 above, further comprising a step of washing the discotic liquid crystal compound solution with water, and contacting the discotic liquid crystal compound solution after washing with a clay mineral as an adsorbent. Compound purification method.
6). 6. The method for purifying a discotic liquid crystal compound according to any one of 1 to 5, wherein the discotic liquid crystal compound solution is dried with a desiccant before contacting the clay mineral.
7). The structure of the discotic liquid crystal compound is represented by the following general formula (I) [wherein R represents an acyl group] The purification of the discotic liquid crystal compound according to any one of 1 to 6 above Method.

8). 8. The method for purifying a discotic liquid crystal compound according to any one of 1 to 7 above, wherein the clay mineral is used in a method of pre-coating a body feed or a sparkler filter.
9. 9. The method for purifying a discotic liquid crystal compound according to any one of 1 to 8 above, wherein the clay mineral is montmorillonite.

According to the purification method of the discotic liquid crystal compound of the present invention, the dehydration step is not necessarily required and the adsorption step can be greatly simplified compared to the conventional method using silica gel and a synthetic adsorbent. It has the advantage that it simplifies the process and significantly reduces waste of dehydrating agent and adsorbent. Further, the discotic liquid crystal compound obtained by the purification method of the present invention is excellent in performance as a discotic liquid crystal material.
That is, according to the present invention, it is possible to provide a method for purifying a discotic liquid crystal compound that is suitable for mass production with high yield, low cost, high productivity, and low solid waste.

Hereinafter, the present invention will be described in more detail.
The discotic liquid crystal compound according to the present invention is characterized by having a discotic molecular portion at the center. The disk-like morphological features of the central part excluding the side chain part can be expressed, for example, as follows for the hydrogen substitute that is the original compound. First, the molecular size is determined as follows.
1) Construct a molecular structure that is as close to a plane as possible, preferably a planar molecular structure. In this case, as the bond distance and bond angle, it is preferable to use standard values corresponding to the orbital mixture. For example, the Chemical Society of Japan, Chemical Handbook 4th edition, Chapter II, Volume 15 (1993 published by Maruzen) You can refer to it.
2) Using the structure obtained in 1) as an initial value, the structure is optimized by a molecular orbital method or a molecular force field method. Examples of the method include Gaussian 92, MOPAC 93, CHARMm / QUANTA, and MM3. Gaussian 92 is preferable.
3) The center of gravity of the structure obtained by structure optimization is moved to the origin, and the coordinate axis is taken as the inertial principal axis (the principal axis of the inertia tensor ellipsoid).
4) A sphere defined by the van der Waals radius is given to each atom, thereby describing the shape of the molecule.
5) Measure the length in the direction of each coordinate axis on the van der Waals surface, and let them be a, b and c, respectively.
When a disk-like form is defined using a, b, and c obtained by the above procedure, preferably a ≧ b> c and a ≧ b ≧ a / 2, more preferably a ≧ b> c and a ≧ It can be expressed as b ≧ 0.7a. Moreover, it is preferable that b / 2> c.

  These characteristics are required as a discotic liquid crystal compound. Here, as specific compounds of the discotic liquid crystal compound, for example, the Chemical Society of Japan, Quarterly Chemical Review No. 22 “Chemicals of Liquid Crystals”, Chapter 5 and Chapter 10 Section 2 (published in 1994). Destrade et al., Mol. Cryst. Liq. Cryst. 71, 111 (1981), B.I. Kohne et al., Angew. Chem. 96, p. 70 (1984), J. Am. M.M. Lehn et al. Chem. Soc. Chem. Commun. , 1794 (1985), J. Am. Zhang, J. et al. S. A study report by Moore et al. Am. Chem. Soc. 116, 2655 (1994), and derivatives of mother nucleus compounds.

  Examples include benzene derivatives, triphenylene derivatives, truxene derivatives, phthalocyanine derivatives, porphyrin derivatives, anthracene derivatives, hexaethynylbenzene derivatives, dibenzopyrene derivatives, coronene derivatives, and phenylacetylene macrocycle derivatives. Furthermore, the cyclic compounds described in the Chemical Society of Japan, “Chemical Review No. 15 New Aromatic Chemistry” (published by the University of Tokyo Press, 1977) and their electronic structures such as heteroatom substitution can be mentioned.

  Examples of the central part precursor that can be the central part of the discotic liquid crystal compound include a central part precursor having a phenolic hydroxyl group, such as a benzene ring, triphenylene ring, truxene ring, phthalocyanine ring, porphyric acid, anthracene ring, hexaethynyl. Examples include compounds in which a hydroxyl group is radially substituted on a benzene ring, dibenzopyrene ring, coronene ring, or phenylacetylene macrocycle ring. The center part precursor used in the present invention is preferably 2,3,6,7,10,11-hexahydroxytriphenylene having a triphenylene ring substituted with a hydroxyl group. A discotic liquid crystal compound is formed by a structure in which these are the central part of the molecule and, for example, an alkanoyloxy group or a substituted benzoyloxy group is radially substituted as its side chain part.

  As the side chain portion precursor, an alkyl halide having 18 or less carbon atoms which may have an ether bond or an unsaturated bond such as allyl bromide, 1-butyl bromide, 1-hexyl bromide, 2-ethoxyethyl bromide, etc. , Allyl alcohol, 1-butanol, 1-hexanol, 2-ethoxyethanol and the like, an alcohol having 18 or less carbon atoms which may have an ether bond or an unsaturated bond, and a side having a carboxylic acid group A chain | strand part precursor is mentioned.

  Examples of the side chain portion precursor having a carboxylic acid that can be a side chain portion include saturated fatty acids (for example, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid), 4 -Alkylbenzoic acids (for example as alkyl groups butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl), 4-alkoxybenzoic acids (for example as alkoxy groups butoxy, pentyloxy, hexyloxy, heptyloxy, octyl) Oxy, nonyloxy, decyloxy, dodecyloxy), and the molecule may contain an aryl group or a heterocyclic group.

  In addition, C.I. Hansch, A.D. Leo, R.A. W. Taft, Chemical Review (Chem. Rev., 1991), Vol. 91, pages 165-195 (American Chemical Society) may be substituted, and representative examples include alkoxy groups and alkyl groups. Group, alkoxycarbonyl group and halogen atom. Further, the molecule may have a functional group such as an ether group, an ester group, a carbonyl group, a thioether group, a sulfoxide group, a sulfonyl group, or an amide group. In particular, in a molecule, a functional group that is weak against acid, for example, a functional group that causes hydrolysis or addition reaction, specifically an α, β-unsaturated carbonyl group {for example, acryloyl [specifically, for example, 4-acryloyloxy Butanoic acid, 6-acryloyloxyhexanoic acid, 8-acryloyloxyoctanoic acid, 10-acryloyloxydecanoic acid, 4- (acryloyloxybutyloxy) benzoic acid, 4- (6-acryloyloxyhexyloxy) benzoic acid, 4- (8-acryloyloxyoctyloxy) benzoic acid, 4- (10-acryloyloxydecyloxy) benzoic acid], methacryloyl [specifically, for example, 4-methacryloyloxybutanoic acid, 6-methacryloyloxyhexanoic acid, 8- Methacryloyloxyoctanoic acid, 10-methacryloyloxy Decanoic acid, 4- (4-methacryloyloxybutyloxy) benzoic acid, 4- (6-methacryloyloxyhexyloxy) benzoic acid, 4- (8-methacryloyloxyoctyloxy) benzoic acid, 4- (10-methacryloyloxydecyl) Oxy) benzoic acid], crotonoyl}, enol ether group {eg vinyl ether [specifically, for example, 4-vinyloxybutanoic acid, 6-vinyloxyhexanoic acid, 8-vinyloxyoctanoic acid, 10-vinyloxydecanoic acid, 4 -(4-vinyloxybutyloxy) benzoic acid, 4- (6-vinyloxyhexyloxy) benzoic acid, 4- (8-vinyloxyoctyloxy) benzoic acid, 4- (10-vinyloxydecyloxy) benzoic acid ], Epoxy group, acetal group, silyl ether group Preferable to the case. The number of atoms in the main chain of the side chain precursor is preferably 2 to 30, more preferably 4 to 20, excluding the carboxylic acid or benzoic acid part.

In the present invention, a central part precursor having a phenolic hydroxyl group that can be a central part of a discotic liquid crystal compound and a side chain part precursor having a carboxylic acid group that can be a side chain part in the form of a mixed acid anhydride ester are esterified. It is a preferred form to synthesize a discotic liquid crystal compound.
Examples of the acid that forms a pair with the carboxylic acid used in the preparation of the mixed acid anhydride derivative include, for example, carbonic acid ester (for example, carbonic acid monoethyl ester), carboxylic acid (for example, pivalic acid, trifluoroacetic acid), and sulfonic acid (for example, , Methanesulfonic acid, toluenesulfonic acid) and inorganic acids (for example, phosphoric acid). Of these, sulfonic acid is preferable, and methanesulfonic acid is more preferable. These acids are reacted with carboxylic acid in the form of acid chloride. The amount of acid chloride used at this time is 0.9 to 1.05 equivalents, preferably 1.0 equivalents, relative to the carboxylic acid. It is.

  Examples of the solvent used when preparing the mixed acid anhydride derivative include 1,2-dimethoxyethane, 1,4-dioxane, toluene, tetrahydrofuran (THF), ethyl acetate, butyl acetate, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK). ) And dimethylformamide (DMF), among which tetrahydrofuran (THF), toluene, ethyl acetate, and butyl acetate are particularly preferable. That is, in the present invention, a nonpolar solvent is preferable, and at least one nonpolar solvent is preferably used as a reaction solvent. Here, as the nonpolar solvent, those having a dielectric constant at 20 ° C. of 10.0 or less are preferable, and more specifically, ethers, aromatic hydrocarbons, esters, aliphatic hydrocarbons, A solvent having no group is preferable, and examples thereof include the above tetrahydrofuran (THF), toluene, ethyl acetate, and butyl acetate. At least one of the solvents used in preparing the mixed acid anhydride derivative is preferably a solvent that is sparingly soluble in water, and a solvent that separates into two layers when water is added is preferable. Specific examples include toluene, ethyl acetate, and butyl acetate.

  Examples of the base used in preparing the mixed acid anhydride derivative include tertiary amines (for example, triethylamine, diisopropylethylamine, N-methylmorpholine) and pyridines (for example, pyridine, picoline, lutidine). Triethylamine and diisopropylethylamine are preferred. The amount used is preferably 1.0 to 2.0 equivalents, more preferably 1.0 to 1.1 equivalents relative to the carboxylic acid. The temperature at the time of preparing the mixed acid anhydride derivative is preferably −30 ° C. to 15 ° C., more preferably −20 ° C. to 5 ° C. As a method for preparing a mixed acid anhydride derivative, for example, acid chloride is dropped into a system of (carboxylic acid + amine + solvent), amine is dropped into a system of (carboxylic acid + acid chloride + solvent), and (acid chloride + solvent). ), (Carboxylic acid + amine + solvent) is added dropwise. In particular, (carboxylic acid + amine + solvent) is preferably added dropwise to the (acid chloride + solvent) system. Examples of the base used for the reaction between the mixed acid anhydride derivative and the hydroxyl group include tertiary amines (for example, triethylamine, diisopropylethylamine, N-methylmorpholine) and pyridines (for example, pyridine, picoline, lutidine). Preferably, triethylamine and diisopropylethylamine are used.

  The central precursor having a phenolic hydroxyl group may be added to the mixed acid anhydride derivative reaction solution in the form of powder, suspension, or solution, or the mixed acid anhydride derivative reaction solution may be added. Good. Examples of the solvent used include dimethyl sulfoxide (DMSO), dimethylformamide (DMF), THF, 1,2-dimethoxyethane, 1,4-dioxane, ethyl acetate, butyl acetate, dichloromethane, chloroform, and acetone. , Preferably DMF, DMSO, THF. Examples of bases used as deoxidizers for trapping acids generated by the activation of phenolic hydroxyl groups and esterification reactions in esterification reactions include tertiary alkylamines (for example, triethylamine, diisopropylethylamine, N-methylmorpholine, N-methylpyrrolidine, N-methylpiperidine), pyridines (for example, pyridine, picolines, lutidines) and anilines (N, N-dimethylaniline, N, N-diethylaniline) are preferable, Tertiary alkylamines (for example, triethylamine, diisopropylethylamine, N-methylmorpholine, N-methylpyrrolidine, N-methylpiperidine), pyridines (for example, pyridine, picolines, lutidines, 4-dimethylaminopyridine (DMAP)) ), Preferably the al, a tertiary alkyl amines (e.g., triethylamine, diisopropylethylamine, N- methylmorpholine, N- methylpyrrolidine, N- methylpiperidine). In addition, in order to activate the mixed acid anhydride and promote the esterification reaction, an electron-excess pyridine compound having no substituent at the α-position [for example, 4-dimethylaminopyridine (DMAP), 4-pyrrolidinopyridine , 4-piperidinopyridine] is preferably used in combination as a catalyst. In the present invention, the esterification reaction solvent is preferably a solvent containing at least one nonpolar solvent as described above, and examples thereof include tetrahydrofuran (THF), toluene, ethyl acetate, and butyl acetate. Moreover, in this invention, it is preferable to use the reaction liquid at the time of preparation of a mixed acid anhydride derivative as it is. Therefore, the reaction solvent at the time of preparing the mixed acid anhydride is preferably an esterification reaction solvent or a part of the reaction solvent.

  The present invention is characterized in that impurities are removed by bringing a clay mineral as an adsorbent into contact with the synthesized discotic liquid crystal compound solution.

  In the present invention, the discotic liquid crystal compound synthesized as described above can be taken out as crystals and dissolved in an organic solvent to form a discotic liquid crystal compound solution, which can be contacted with a clay mineral as an adsorbent.

  As the organic solvent used, an organic solvent having a dielectric constant of 20 or less and a donor number of 21 or less can be used. Specifically, aromatic hydrocarbon solvents such as toluene, ethylbenzene, xylene and cumene, halogen solvents such as chloroform, dichloromethane and chlorobenzene, ether solvents such as diethyl ether, tetrahydrofuran and dioxane, ethyl acetate, propyl acetate and acetic acid Examples thereof include ester solvents such as butyl and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. A combination of these solvents can also be used.

  Apart from this, in the present invention, a clay mineral as an adsorbent can be brought into contact with the reaction solution after the esterification reaction.

Examples of the clay mineral used as the adsorbent in the present invention include swellable clay minerals such as smectite and vermiculite, more preferably a smectite clay mineral, particularly preferably montmorillonite (or sometimes expressed as purified bentonite). It is. The amount of the adsorbent used is preferably 0.1 g to 1.5 g, more preferably 0.1 g to 1.0 g, and more preferably 0.1 g to 0 g with respect to 1 g of the theoretical yield of the target discotic liquid crystal compound. More preferably, 6 g is used.
In the present invention, the adsorbent is divided into two or more addition treatments (specifically, two or more divided additions) rather than a single addition treatment, thereby reducing the total amount of adsorbent used, and an alignment inhibitor Although it is effective for the removal, since the operation becomes complicated as the number of times increases, it is preferably 1 to 5 times, more preferably 1 to 2 times. Table 1 lists the clay minerals suitable for the present invention.

As the clay mineral used in the present invention, various naturally available clay minerals can be used as they are, but preferably, a smectite clay mineral obtained in nature, or a smectite clay mineral obtained in nature is further purified. High-purity smectite-based clay minerals, synthetic smectite-based clay minerals that are artificially synthesized, and more preferably, high-purity smectite-based clay minerals obtained by further refining naturally obtained smectite-based clay minerals, or It is a synthetic smectite clay mineral that is artificially synthesized, and particularly preferably montmorillonite (high-purity bentonite) obtained by refining a bentonite mineral that is naturally obtained, or synthetic montmorillonite that is artificially synthesized.
Bentonite (montmorillonite) and hectorite are the most important natural smectite clay minerals because of their availability. High-purity bentonite (montmorillonite) and high-purity hectorite obtained by refining these are the most important. It is available from the following.

<Origin of montmorillonite (high purity bentonite)>
Montmorillonite K10 (Sigma-Aldrich) ss
Kunipia F (Kunimine Industry Co., Ltd.)
Wenger A (Hojun Co., Ltd.)

<High purity hectorite source>
BENTONE (R) GS (Elementis Specialties)

  Synthetic smectite clay minerals synthesized artificially can be produced by hydrothermal synthesis. For example, hectorite is produced by the method of Japanese Patent Publication No. 61-12848, and saponite is produced by the method of Japanese Patent Publication No. 6-62290. it can.

  The contact treatment between the discotic liquid crystal compound solution and the clay mineral as the adsorbent (hereinafter referred to as treatment with an adsorbent) is preferably performed under stirring. The treatment time is preferably 30 minutes to 90 minutes, and more preferably 40 minutes to 80 minutes. When treating with an adsorbent, it may be heated, but is preferably carried out at room temperature. In the present invention, after the treatment with the adsorbent as described above, it is preferable to add a solvent in which the discotic liquid crystal compound is difficult to dissolve to the solution after the treatment, and crystallize and take out the solution as it is. Is preferably an alcohol solvent. The alcohol solvent is preferably methanol, ethanol, propanol, isopropanol, or butanol, more preferably methanol, ethanol, and particularly preferably methanol.

  In the present invention, when the reaction solution after the esterification reaction is treated with an adsorbent, the adsorbent may be added directly to the reaction solution, or before the adsorbent is added, the reaction solution and water are added. And the separated organic layer may be treated with an adsorbent. In the present invention, it is preferable to mix the reaction solution and water and treat the separated organic layer with an adsorbent.

  In the present invention, the reaction solution or the separated organic layer can be dried and then treated with an adsorbent. For drying, an inorganic desiccant is preferably used. Examples of these desiccants include anhydrous magnesium sulfate, mirabilite, molecular sieve, and silica gel, but anhydrous magnesium sulfate and mirabilite are preferred, and anhydrous magnesium sulfate is particularly preferred. Moreover, it is preferable to stir after adding a desiccant. The desiccant added to the reaction solution or the separated organic layer is preferably filtered after 20 minutes to 120 minutes, more preferably after 30 minutes to 90 minutes.

  In the present invention, the adsorbent is preferably used in a body feed or a method of pre-coating on a sparkler filter.

  In the present invention, the discotic liquid crystal compound particularly preferably applied is a compound represented by the following general formula (I).

  Here, R represents an acyl group, and the acyl group is an aliphatic or aromatic acyl group and may have a substituent. These acyl groups are the carboxylic acid-based acyl groups described in the side chain portion precursor, and the preferred ranges and specific examples in the above description are applied as they are. Specific examples of the compound represented by the general formula (I) are shown below. However, the scope of the present invention is not limited to these.

EXAMPLES Next, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.
Below, synthesis examples and physical property measurements of the discotic liquid crystal compound used in the present invention, further performance of the compound as a liquid crystal compound, production example of an optically anisotropic material using a composition containing the compound, and evaluation of the performance An example is given.

Example 1-1
<Mesylation reaction>
A 500 ml three-necked flask was charged with 58.5 g of butyl acetate, 0.11 g of nitrobenzene and 17.77 g (0.16 mol) of methanesulfonyl chloride and cooled to 4 ° C., and 58.4 g of THF, 0.05 g of nitrobenzene, 14.31 g of triethylamine. (0.14 mol), diisopropylethylamine 3.23 g (0.025 mol) and 4- (4-acryloyloxybutyloxy) benzoic acid 40 g (0.15 mol) in solution were added dropwise at 4-8 ° C., Stir for 1 hour after dropping.

<Esterification>
To the mesylation reaction solution, 10.91 g (0.11 mol) of triethylamine, 4.65 g (0.04 mol) of diisopropylethylamine, 0.925 g (8 mmol) of 4-dimethylaminopyridine, and 6.6 g of THF are added. After the addition, 7.21 g (0.022 mol) of HHTP dissolved in 76 g of THF was added dropwise at 4 to 10 ° C. and reacted at 10 ° C. for 2 hours, whereby 2,3,6,7,10,11-hexa [4 -(Acroyloxybutoxy) benzoyloxy] triphenylene was synthesized.
<Washing>
304 g of well water is added to the esterification reaction solution and stirred at 20 ° C. for 5 minutes. After separation, the aqueous layer is discarded, and 18.24 g of NaCl is dissolved in 304 g of well water and added. After separation, discard the aqueous layer.
<Adsorption>
11.2 g of montmorillonite K10 (Sigma-Aldrich) is added to the dehydrated liquid, and the mixture is stirred for 1 hour and filtered through Celite.
<Crystal>
Add 381 ml of methanol to the purified solution and stir at 15 ° C. for 1 hour 30 minutes. Thereafter, the mixture was cooled to −6 ° C., stirred for 30 minutes, and filtered to obtain 2,3,6,7,10,11-hexa [4- (acryloyloxybutoxy) benzoyloxy] triphenylene (yield 35.6 g, yield 89). %).

Example 1-2
<Mesylation reaction>
A 500 ml three-necked flask was charged with 58.5 g of butyl acetate, 0.11 g of nitrobenzene and 17.77 g (0.16 mol) of methanesulfonyl chloride and cooled to 4 ° C., and 58.4 g of THF, 0.05 g of nitrobenzene, 14.31 g of triethylamine. (0.14 mol), a solution of diisopropylethylamine 3.23 g (0.025 mol) and 4- (4-acryloyloxybutyloxy) benzoic acid 40 g (0.15 mol) was added dropwise at 4-8 ° C., Stir for 1 hour after dropping.

<Esterification>
To the mesylation reaction solution, 10.91 g (0.11 mol) of triethylamine, 4.65 g (0.04 mol) of diisopropylethylamine, 0.925 g (8 mmol) of 4-dimethylaminopyridine, and 6.6 g of THF are added. After the addition, 7.21 g (0.022 mol) of HHTP dissolved in 76 g of THF was added dropwise at 4-10 ° C., and reacted at 10 ° C. for 2 hours, whereby 2,3,6,7,10,11-hexa [4 -(Acroyloxybutoxy) benzoyloxy] triphenylene was synthesized.

<Washing>
304 g of well water is added to the esterification reaction solution and stirred at 20 ° C. for 5 minutes. After separation, the aqueous layer is discarded, and 18.24 g of NaCl is dissolved in 304 g of well water and added. After separation, discard the aqueous layer.
<Crystal>
Add 381 ml of methanol to the purified solution and stir at 15 ° C. for 1 hour 30 minutes. Thereafter, the mixture was cooled to −6 ° C., stirred for 30 minutes, filtered, and crude 2,3,6,7,10,11-hexa [4- (acryloyloxybutoxy) benzoyloxy] triphenylene (yield 36.2 g, yield). 90%).
<Adsorption>
Crude crystals obtained by the above crystallization (crystals equivalent to those obtained in Comparative Example 3) 36.2 g and 4-methoxyphenol 72 mg were dissolved in 90.5 ml of butyl acetate, and montmorillonite K10 (Sigma-Aldrich) 11 Add 2 g, stir for 1 hour, and filter through Celite.
<Crystal>
290 ml of methanol is added to the purified solution and stirred at 15 ° C. for 1 hour and 30 minutes. Thereafter, the mixture was cooled to −6 ° C., stirred for 30 minutes, filtered, and 2,3,6,7,10,11-hexa [4- (acryloyloxybutoxy) benzoyloxy] triphenylene (yield 34.5 g, yield 86). %).

Comparative Example-1
<Mesylation reaction>
A 500 ml three-necked flask was charged with 58.5 g of butyl acetate, 0.11 g of nitrobenzene and 17.77 g (0.16 mol) of methanesulfonyl chloride and cooled to 4 ° C., and 58.4 g of THF, 0.05 g of nitrobenzene, and 14.3 of triethylamine. A solution of 31 g (0.14 mol), diisopropylethylamine 3.23 g (0.025 mol) and 4- (4-acryloyloxybutyloxy) benzoic acid 40 g (0.15 mol) was added dropwise at 4-8 ° C. After dropping, the mixture is stirred for 1 hour.

<Esterification>
To the mesylation reaction solution, 10.91 g (0.11 mol) of triethylamine, 4.65 g (0.04 mol) of diisopropylethylamine, 0.925 g (8 mmol) of 4-dimethylaminopyridine, and 6.6 g of THF are added. After the addition, 7.21 g (0.022 mol) of HHTP dissolved in 76 g of THF was added dropwise at 4-10 ° C., and reacted at 10 ° C. for 2 hours, whereby 2,3,6,7,10,11-hexa [4 -(Acroyloxybutoxy) benzoyloxy] triphenylene was synthesized.

<Washing>
304 g of well water is added to the esterification reaction solution and stirred at 20 ° C. for 5 minutes. After separation, the aqueous layer is discarded, and 18.24 g of NaCl is dissolved in 304 g of well water and added. After separation, discard the aqueous layer.
<Dehydration>
11.2 g of anhydrous magnesium sulfate is added to the above extract and stirred at 20 ° C. for 1 hour, and the magnesium sulfate is removed by filtration.
<Adsorption>
7.44 g of KYOWARD 700SN (product of Kyowa Chemical Industry Co., Ltd.) is added to the dehydrated liquid, and the mixture is stirred for 1 hour and filtered through Celite. Next, 12.6 g of Kyoward 700SN (a synthetic adsorbent composed of silica and alumina) is added to the filtrate, and the mixture is stirred for 1 hour and filtered through Celite.
<Crystal>
Add 381 ml of methanol to the purified solution and stir at 15 ° C. for 1 hour 30 minutes. Thereafter, the mixture was cooled to −6 ° C., stirred for 30 minutes, filtered, and 2,3,6,7,10,11-hexa [4- (acryloyloxybutoxy) benzoyloxy] triphenylene (yield 35.2 g, yield 86). %).

Comparative Example-2
<Mesylation reaction>
A 500 ml three-necked flask was charged with 58.5 g of butyl acetate, 0.11 g of nitrobenzene and 17.77 g (0.16 mol) of methanesulfonyl chloride and cooled to 4 ° C., and 58.4 g of THF, 0.05 g of nitrobenzene, 14.31 g of triethylamine. (0.14 mol), diisopropylethylamine 3.23 g (0.025 mol) and 4- (4-acryloyloxybutyloxy) benzoic acid 40 g (0.15 mol) in solution were added dropwise at 4-8 ° C., Stir for 1 hour after dropping.

<Esterification>
To the mesylation reaction solution, 10.91 g (0.11 mol) of triethylamine, 4.65 g (0.04 mol) of diisopropylethylamine, 0.925 g (8 mmol) of 4-dimethylaminopyridine, and 6.6 g of THF are added. After the addition, 7.21 g (0.022 mol) of HHTP dissolved in 76 g of THF was added dropwise at 4-10 ° C., and reacted at 10 ° C. for 2 hours, whereby 2,3,6,7,10,11-hexa [4 -(Acroyloxybutoxy) benzoyloxy] triphenylene was synthesized.

<Washing>
304 g of well water is added to the esterification reaction solution and stirred at 20 ° C. for 5 minutes. After separation, the aqueous layer is discarded, and 18.24 g of NaCl is dissolved in 304 g of well water and added. After separation, discard the aqueous layer.
<Dehydration>
11.2 g of anhydrous magnesium sulfate is added to the above extract and stirred at 20 ° C. for 1 hour, and the magnesium sulfate is removed by filtration.
<Crystal>
381 ml of methanol is added to the dehydrating solution and stirred at 15 ° C. for 1 hour and 30 minutes. Thereafter, the mixture was cooled to −6 ° C., stirred for 30 minutes, filtered, and 2,3,6,7,10,11-hexa [4- (acryloyloxybutoxy) benzoyloxy] triphenylene (yield 35.2 g, yield 86). %).

Comparative Example-3
<Mesylation reaction>
A 500 ml three-necked flask was charged with 58.5 g of butyl acetate, 0.11 g of nitrobenzene and 17.77 g (0.16 mol) of methanesulfonyl chloride and cooled to 4 ° C., and 58.4 g of THF, 0.05 g of nitrobenzene, 14.31 g of triethylamine. (0.14 mol), diisopropylethylamine 3.23 g (0.025 mol) and 4- (4-acryloyloxybutyloxy) benzoic acid 40 g (0.15 mol) in solution were added dropwise at 4-8 ° C., Stir for 1 hour after dropping.

<Esterification>
To the mesylation reaction solution, 10.91 g (0.11 mol) of triethylamine, 4.65 g (0.04 mol) of diisopropylethylamine, 0.925 g (8 mmol) of 4-dimethylaminopyridine, and 6.6 g of THF are added. After the addition, 7.21 g (0.022 mol) of HHTP dissolved in 76 g of THF was added dropwise at 4-10 ° C., and reacted at 10 ° C. for 2 hours, whereby 2,3,6,7,10,11-hexa [4 -(Acroyloxybutoxy) benzoyloxy] triphenylene was synthesized.

<Washing>
304 g of well water is added to the esterification reaction solution and stirred at 20 ° C. for 5 minutes. After separation, the aqueous layer is discarded, and 18.24 g of NaCl is dissolved in 304 g of well water and added. After separation, discard the aqueous layer.
<Crystal>
381 ml of methanol is added to the above washing solution and stirred at 15 ° C. for 1 hour and 30 minutes. Thereafter, the mixture was cooled to −6 ° C., stirred for 30 minutes, and then filtered to obtain 2,3,6,7,10,11-hexa [4- (acryloyloxybutoxy) benzoyloxy] triphenylene (yield 36.0 g, yield 90). %).

Example 2 (Measurement of physical properties of a discotic liquid crystal compound)
In HPLC, GPC, and NMR, it was difficult to detect the physical property differences of the discotic liquid crystal compounds of Examples 1-1 and 1-2 and Comparative Examples 2 to 3, but physical property differences could be found by TLC measurement. done. In particular, it was found that the result of the spot 24 mm from the origin of the TLC secondary development has a very high correlation with the performance of the discotic liquid crystal compound.
<One-dimensional expansion method>
4 μl of a 10% compound ethyl acetate solution is spotted with MICROCAPS on a MERCH (5715) silica gel plate and developed 9.5 cm with ethyl acetate. The origin portion (spot portion) of this TLC plate is quantified under the following chromatoscanner measurement conditions.
<Two-dimensional expansion method>
The TLC plate developed under the conditions of the one-dimensional development method is further developed on the secondary side with THF / methanol = 9/1 (v / v) (development distance is 9.5 cm). A spot of 24 mm from the origin on the secondary development side is quantified under the following chromatographic scanner measurement conditions.

These results are shown in Table 2 below. From the results of Table 2 below, in the sample that was not subjected to the adsorption treatment only by anhydrous magnesium sulfate as in Comparative Example 2, and the sample that was not subjected to the dehydration and adsorption treatment in anhydrous magnesium sulfate as in Comparative Example 3, It can be seen that there are many origin component discotic liquid crystal compounds and the orientation as a discotic liquid crystal compound is poor. On the other hand, the compound obtained in Example 1-2 of the present invention showed an origin component AREA value equivalent to that of the compound obtained in Comparative Example 1, but Example 1-1 showed a high value. However, it was found that Example 1-1 showed high orientation even though the origin component was high. Therefore, after drying the primary developed TLC plate, it is further developed on the secondary side with THF / methanol = 9/1 (v / v), and each spot on the secondary development side correlates with the performance as a discotic liquid crystal compound. When the properties were compared, it was found that the correlation between the 24 mm portion component and the orientation was high from the origin on the secondary development side. It was found that the liquid crystal orientation deteriorates remarkably when a component of 24 mm from the origin on the secondary development side is preparatively separated and used together with a discotic liquid crystal compound. From this, it was found that the 24 mm portion component from the origin on the secondary development side is the main substance that inhibits orientation.
This is also clear from the fact that the area of the 24 mm portion component is low from the origin on the secondary development side of Example 1-2 and Comparative Example 1, and the performance of the retardation film shown in Example 4 described later correlates. is there.

<Chromatoscanner measurement conditions>
Model name: Shimadzu Corporation DUAL WAVELENGTH CHROMATO SCANNER CS-930
Measurement wavelength: λ254nm Scan mode: Zigzag mode Scan width: 7mm

Example 3 (Composition of a discotic liquid crystal compound and preparation of an optically anisotropic material using the same)
[Example of WV-SA (preparation by hand coating)]
(Saponification and alignment film formation)
A 1.5 N KOH-isopropyl alcohol solution was applied to cellulose acetate (CA-1) at 25 ml / m ^{2 and} dried at 25 ° C. for 5 seconds. The film was washed with running water for 10 seconds, and the film surface was dried by blowing air at 25 ° C. Thereafter, an alignment film coating solution having the following composition was applied at 28 ml / m ² with a # 16 wire bar coater. Drying was performed with warm air of 60 ° C. for 60 seconds, and further with warm air of 90 ° C. for 150 seconds.

――――――――――――――――――――――――――――――――――――
Alignment film coating solution ――――――――――――――――――――――――――――――――――――
Modified polyvinyl alcohol 20 parts by mass Water 360 parts by mass Methanol 120 parts by mass Glutaraldehyde 0.5 parts by mass ――――――――――――――――――――――――――――― ―――――――

(Formation of optically anisotropic layer)
A discotic liquid crystal compound coating solution having the following composition is applied with a # 4 wire bar coater, heated in a high-temperature bath at 125 ° C. for 3 minutes to align the discotic liquid crystal compound, and then UV is irradiated using a high-pressure mercury lamp. Irradiated with 500 mJ / cm ² and allowed to cool to room temperature, an optical compensation sheet KS-1 was prepared.

――――――――――――――――――――――――――――――――――――
Discotic liquid crystal compound coating solution ――――――――――――――――――――――――――――――――――――
Discotic liquid crystal compound 9.1 parts by mass Ethylene oxide-modified trimethylolpropane acrylate 0.9 parts by mass (V # 360, Osaka Organic Chemical Co., Ltd.)
Cellulose acetate butyrate 0.2 parts by mass (CAB551-0.2 Eastman Chemical)
0.05 parts by weight of cellulose acetate butyrate (CAB531-1 Eastman Chemical)
Irgacure 907 3.0 parts by mass Kayacure DETX (manufactured by Nippon Kayaku Co., Ltd.) 0.1 parts by mass Methyl ethyl ketone 25.9 parts by mass ――――――――――――――――――― ――――――――――――――――

  The thickness of the optically anisotropic layer was 1.8 μm.

Example 4 (Performance evaluation of retardation film)
The alignment property of the liquid crystal phase is important as a performance item of the discotic liquid crystal compound such as an optically anisotropic material such as a retardation film. As the evaluation method, the “quenching value” described below was measured, and the discotic liquid crystal compound was evaluated.

[Extinction value]
The transmittance when the optical compensation sheet was arranged between the two polarizing plates arranged in crossed Nicol so that the transmittance was minimized was measured, and the orientation of the discotic liquid crystal compound was evaluated. The lower the extinction value, the higher the orientation. From the results in Table 3, it can be seen that the compounds obtained in Examples 1-1 and 1-2 of the present invention and Comparative Example 1 all exhibit high orientation.
Measurement wavelength: 550 nm
The transmittance of the polarizing plate in the paranicol arrangement is set to 100%.

Claims (9)

  A method for purifying a discotic liquid crystal compound that removes impurities from a discotic liquid crystal compound solution containing a synthesized discotic liquid crystal compound, the method comprising contacting a clay mineral as an adsorbent with the discotic liquid crystal compound solution A method for purifying discotic liquid crystal compounds.   The crystal of the synthesized discotic liquid crystal compound is dissolved in an organic solvent to obtain a discotic liquid crystal compound solution, and a clay mineral as an adsorbent is brought into contact with the discotic liquid crystal compound solution. Purification method of discotic liquid crystal compound.   A clay mineral as an adsorbent is brought into contact with a discotic liquid crystal compound solution obtained by reacting a central part precursor that can be a central part of a discotic liquid crystal compound with a side chain part precursor that can be a side chain part. The method for purifying a discotic liquid crystal compound according to claim 1.   It is obtained by reacting a central part precursor having a phenolic hydroxyl group that can be a central part of a discotic liquid crystal compound with a side chain part precursor having a carboxylic acid group that can be a side chain part in the form of a mixed acid anhydride derivative. The method for purifying a discotic liquid crystal compound according to claim 3, wherein clay mineral as an adsorbent is brought into contact with the discotic liquid crystal compound solution.   The discotic according to any one of claims 1 to 4, further comprising a step of washing the discotic liquid crystal compound solution with water, and contacting the discotic liquid crystal compound solution after the washing with a clay mineral as an adsorbent. A method for purifying a liquid crystal compound.   The method for purifying a discotic liquid crystal compound according to any one of claims 1 to 5, wherein the discotic liquid crystal compound solution is dried with a desiccant before contacting the clay mineral. The structure of the discotic liquid crystal compound is represented by the following general formula (I) [wherein R represents an acyl group]. The discotic liquid crystal compound according to any one of claims 1 to 6, Purification method.

  The method for purifying a discotic liquid crystal compound according to any one of claims 1 to 7, wherein the clay mineral is used in a method of precoating a body feed or a sparkler filter.   The method for purifying a discotic liquid crystal compound according to any one of claims 1 to 8, wherein the clay mineral is montmorillonite.