JP3073760B2 - Pyrimidine liquid crystal compounds - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel pyrimidine-based liquid crystal compound useful for a display device.

[Prior art] Currently, TN (twisted nematic) is used as a liquid crystal display device.
The type display method is most widely used. This TN liquid crystal display has many advantages such as low driving voltage and low power consumption. However, they are inferior to light emitting devices (cathode tubes, electroluminescence, plasma displays, etc.) in response speed. A new TN display device with a twist angle of 180 to 270 ° has been developed, but the response speed is still inferior. Although various improvements have been made in this way, a TN type display element having a high response speed has not been realized. However, in a new display method using a ferroelectric liquid crystal, which has been actively studied recently, there is a possibility that the response speed can be remarkably improved (NAClark et al .; Applied Phys.lett., 36, 899 (198).
0)). This method uses a chiral smectic phase such as a chiral smectic C phase exhibiting ferroelectricity. It is known that not only the chiral Sc phase but also the phases such as chiral smectic F, G, H and I exhibit ferroelectricity.

Many characteristics are required for ferroelectric liquid crystal materials used in ferroelectric liquid crystal display devices actually used, but at present, a single compound cannot satisfy such characteristics, It is necessary to use a ferroelectric liquid crystal composition obtained by mixing a liquid crystal compound or a non-liquid crystal compound.

Further, not only a ferroelectric liquid crystal composition consisting of a ferroelectric liquid crystal compound alone, but also a compound exhibiting a non-chiral smectic C, F, G, H, I, etc. It has been reported that a composition can be used as a basic substance, and one or more compounds exhibiting a ferroelectric liquid crystal phase can be mixed therewith to form a ferroelectric liquid crystal composition as a whole. Furthermore, a compound or composition exhibiting a phase such as smectic C is used as a basic substance, and one or more compounds that are optically active but do not exhibit a ferroelectric liquid crystal phase are mixed to form a ferroelectric liquid crystal composition as a whole. (Mol. Cryst. Liq. Cryst., 89, 327 (1982)).

Taken together, it can be seen that a ferroelectric liquid crystal composition can be formed by mixing one or more optically active compounds with a basic substance regardless of whether or not it exhibits a ferroelectric liquid crystal phase.

As these basic substances, various compounds exhibiting a non-chiral smectic liquid crystal phase such as smectic C are used, but practically a liquid crystal compound or a mixture exhibiting a smectic C phase in a wide temperature range including room temperature is desirable. As components of these smectic C liquid crystal mixtures,
And liquid crystal compounds such as phenylbenzoate, biphenyl, phenylpyridine and 5-alkyl-2- (4-alkoxyphenyl) pyrimidine.

[Problems to be Solved by the Invention] However, it is determined whether or not a chiral smectic C liquid crystal material obtained by adding an optically active compound thereto exhibits excellent performance in a liquid crystal display utilizing ferroelectricity. , The final evaluation has not yet been obtained. This is because liquid crystal displays utilizing ferroelectricity have not been technically completed. Therefore, at present, it is necessary to carry out various tests on a new material for a smectic C liquid crystal composition.

[Means for Solving the Problems] The present inventors have conducted intensive studies on a novel liquid crystal compound useful for the smectic C liquid crystal composition, which is suitable for use as described above, and as a result, the present invention has been achieved. did. That is, the present invention relates to the general formula Wherein R and R ′ are an alkyl group having 1 to 18 carbon atoms;
X ₁ and X ₂ are a single bond (direct bond), -O-, -S- or-
C≡C-, m and n are 1, Y is -C≡C-, and A is a 1,4-phenylene group or a 2,6-naphthylene group which may be substituted by a fluorine atom. A pyrimidine-based liquid crystal compound represented by the formula:

In the general formula (1), examples of the alkyl group having 1 to 18 carbon atoms for R and R ′ include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group,
n-heptyl group, n-octyl group, n-nonyl group, n-
Decyl, n-undecyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl and the like.

Of these, an alkyl group having 3 to 14 carbon atoms is preferable.

A is preferably substituted by a fluorine atom,
4-phenylene group, 4,4'-biphenylene group or 2,6-
It is a naphthylene group.

Examples of a group in which one or two CH groups present in a 1,4-phenylene group or a 4,4'-biphenylene group are replaced by N include: And so on.

Specific examples of the compound represented by the general formula (1) include compounds having groups as shown in Tables 1 to 4.

In Table 1, each symbol represents the following groups.

BUT; nC ₄ H ₉ − PEN; nC ₅ H ₁₁ − HEX; nC ₆ H ₁₃ − HEP; nC ₇ H ₁₅ − OCT; nC ₈ H ₁₇ − NON; nC ₉ H ₁₉ − DEC; nC ₁₀ H ₂₁ − UND nC ₁₁ H ₂₃ -DOD; nC ₁₂ H ₂₅ -NAPHTHIL; 2,6-naphthylene group; a compound represented by the general formula (1) representing a single bond can be synthesized, for example, through the following steps. (Where R, X ₁ , X ₂ , A and R ′
Is the same as in the case of the general formula (1)) That is, the compound of the present invention is obtained by reacting the compound of the general formula (2) with the compound of the general formula (3) in triethylamine under an inert gas atmosphere using a zero-valent or divalent palladium catalyst. The compound of 1a) can be obtained.

Or That is, the compound of the general formula (4) is reacted with a compound of the general formula (2) and 3-methyl-1-butyn-3-ol in triethylamine under an inert gas atmosphere using a zero-valent or divalent palladium catalyst. After forming the compound, the compound of the general formula (5) can be obtained by reacting powdered sodium hydroxide in anhydrous toluene. General formula (5)
Is reacted with a compound of the general formula (6) in triethylamine under an inert gas atmosphere using a zero-valent or divalent palladium catalyst to obtain the compound of the general formula (1a) of the present invention. Can be obtained.

The compound of the general formula (2) can be synthesized, for example, through the following steps.

That is, a compound of the general formula (8) obtained by reacting a compound of the general formula (7) with urea in the presence of an acid catalyst is reacted with a halogenating agent (for example, phosphorus oxychloride) to form a compound of the general formula (2). A compound can be obtained.

The compound of the general formula (7) can be synthesized, for example, through the following steps.

That is, a compound of the general formula (10) obtained by reacting a compound of the general formula (9) with ethyl orthoformate is reacted with a Vilsmeier reagent (for example, a reaction product of phosphorus oxychloride and dimethylformamide) to form a compound. Equation (7a)
Can be obtained.

That is, a compound of the general formula (11) and bromoacetaldehyde diethyl acetal are converted into anhydrous dimethylformamide,
After heating in anhydrous dimethyl sulfoxide or anhydrous tetrahydrofuran to obtain a compound of the general formula (12), the compound is reacted with a Vilsmeier reagent (eg, a reaction product of phosphorus oxychloride and dimethylformamide) to give a compound of the general formula (7b) Can be obtained.

The compounds of the general formulas (3) and (6) can be synthesized, for example, through the following steps.

That is, the compound of the general formula (6a), which is a raw material of the compound of the present invention, can be obtained by alkylating the compound of the general formula (13) with an alkylating agent (for example, an alkyl halide). The compound of the general formula (6a) is converted to 3-methyl-
1-butyn-3-ol is reacted with triethylamine in an inert gas atmosphere using a zero-valent or divalent palladium catalyst to give a compound of the general formula (14), and then powdered in anhydrous toluene. By reacting sodium, a compound of the general formula (3a), which is a raw material of the compound of the present invention, can be obtained.

That is, the compound of the general formula (17) can be obtained by reacting the compound of the general formula (16) obtained by esterifying the compound of the general formula (15) with benzoyl chloride with phenylboric acid in the presence of a palladium catalyst. A compound of the general formula (17) is converted into a halogenating agent (for example, periodic acid +
After halogenation with iodine), the compound is hydrolyzed with an alkali (eg, sodium hydroxide) and isolated and purified to give the compound of the general formula (19). The compound of the general formula (6b), which is a raw material of the compound of the present invention, is obtained by reacting the compound of the general formula (19) with an alkali metal hydroxide and then alkylating the compound with an alkylating agent (eg, an alkyl halide). Can be obtained. General formula (6b)
Is reacted with 3-methyl-1-butyn-3-ol in triethylamine under an inert gas atmosphere using a zero-valent or divalent palladium catalyst to give a compound of the general formula (23). By reacting powdered sodium hydroxide in toluene, the compound of the general formula (3b), which is a raw material of the compound of the present invention, can be obtained.

That is, the compound of the general formula (8c), which is a raw material of the compound of the present invention, can be obtained by reacting the compound of the general formula (22) with a halide of an alkali metal after diazotization. Compound of general formula (8c) and 3-methyl-1
By reacting -butyn-3-ol in triethylamine under an inert gas atmosphere using a zero-valent or divalent palladium catalyst, a compound of the general formula (23) can be obtained. The compound of the general formula (3c), which is a raw material of the compound of the present invention, can be obtained by reacting the compound of the general formula (23) with sodium hydroxide powder in anhydrous toluene.

That is, the compound of the general formula (1b), which is the compound of the present invention, can be obtained by hydrogenating the compound of the general formula (1a) using palladium carbon under a hydrogen atmosphere.

That is, the compound of the general formula (25) can be obtained by reacting the compound of the general formula (24) with hydrogen chloride gas in dry ethanol and then reacting with the ammonia gas. The compound of the general formula (2) is heated and refluxed in ethanol or methanol in the presence of a base (for example, sodium metal) to give the compound of the general formula (2).
The compound of 6) can be obtained. By reacting the compound of the general formula (26) with the compound of the general formula (3 ') in triethylamine under an inert gas atmosphere using a zero-valent or divalent palladium catalyst, the compound of the present invention represented by the general formula Compound (1c) can be obtained.

That is, the compound of the general formula (1c ′) is
The compound of the general formula (1d), which is the compound of the present invention, can be obtained by hydrogenation using palladium carbon.

The liquid crystal is generally used as a liquid crystal composition composed of two or more components, and the liquid crystal compound of the present invention can also be used as a component of the liquid crystal composition. The liquid crystal composition includes a smectic liquid crystal, for example, a smectic liquid crystal having no optically active site [2-p-alkyloxyphenyl-5-alkylpyrimidine, 2-p-alkylphenyl-5-alkyloxypyrimidine, 2-p-alkanoyl. Oxyphenyl-5-alkylpyrimidine, 2-p-alkyloxycarbonylphenyl-5-alkylpyrimidine, 2
-P-alkylphenyl-5-p-alkyloxyphenylpyrimidine, 2-p-alkyloxy-m-fluorophenyl-5-alkylpyrimidine, 2-p-alkyloxyphenyl-5- (trans-4-alkylcyclohexyl) Pyrimidine, 2-p-alkyloxyphenyl-5-alkylpyridine, 2-p-alkyloxy-
m-fluorophenyl-5-alkylpyridine, 2-p
-(P'-alkylphenyl) phenyl-5-alkylpyrimidine, 2-p-alkylphenyl-5-p-alkylphenylpyrimidine, p-alkyloxyphenyl-5-alkylpicolinate, 2-p-alkyloxyphenyl- 5-alkyloxypyrazine, 2-p-alkylphenyl-5-alkylpyrimidine, 2-p-alkyloxyphenyl-5-alkyloxypyrimidine,
2-p-alkylphenyl-5-alkyloxypyrimidine, 4-alkyloxy-4'-biphenylcarboxylic acid-p '-(alkyloxycarbonyl) phenyl ester, 4-alkyloxy-4'-biphenylcarboxylic acid-alkyl ester And / or ferroelectric crystals [optically active 4-alkyloxy-4'-biphenylcarboxylic acid-p '-(2-methylbutyloxycarbonyl) phenyl ester, optically active 4-n-alkyloxy-4'- Biphenylcarboxylic acid-2-methylbutyl ester, optically active p-alkyloxybenzylidene-
p'-Amino-2-chloropropylcinnamate, optically active p-alkyloxybenzylidene-p'-amino-
2-methylbutyl cinnamate etc.] and / or ordinary chiral smectic liquid crystal [optically active 4- (p-alkyloxybiphenyl-p'-oxycarbonyl)-
4 '-(2-methylbutyloxycarbonyl) cyclohexane, optically active pn-alkyloxybenzylidene-p'-(2-methylbutyloxycarbonyl) aniline, etc.]. Further, it may contain a chiral compound having no liquid crystallinity and / or a dichroic dye, for example, an anthraquinone dye or an azo dye.

A liquid crystal composition exhibiting ferroelectricity causes an optical switching phenomenon when a voltage is applied, and a display element having a fast response utilizing this phenomenon can be produced (for example, JP-A-56-107216,
JP-A-59-118744, NA Clark (NACl
ark), ST Lagerwal
l); Applied Physics Letter
ysics Lttetter) 36 , 899 (1980), etc.].

The liquid crystal composition of the present invention has a cell spacing of 0.5 to 10 μm.
m, preferably 0.5 to 3 μm in a liquid crystal cell,
By installing a polarizer on both sides, it can be used as an optical switching element (display element).

The above-mentioned liquid crystal cell can be manufactured by providing a transparent electrode and bonding two glass substrates whose surfaces are subjected to an alignment treatment with a spacer interposed therebetween.

Examples of the spacer include alumina beads, glass fibers, and polyimide films. As the orientation treatment method, a usual orientation treatment, for example, a polyimide film, a rubbing treatment, a SiO oblique deposition, or the like can be applied.

EXAMPLES Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited thereto.

Example 1 Production of Compound No. 8 in Table 1 β-n-heptyl-α-dimethylaminoacrolein (n-heptyl acetaldehyde diethyl acetal obtained by reacting n-octyl magnesium bromide with ethyl orthoformate) It can be obtained by the action of a Vilsmeier reagent.) In a solution of 15.0 g and 6.8 g of urea dissolved in 200 ml of ethanol, 3.0 g of concentrated hydrochloric acid was added, and the mixture was heated under reflux for 15 hours. After completion of the reaction, ethanol was removed and water was added. After neutralization by adding sodium hydroxide, the resulting precipitate was filtered and dried. By recrystallization from toluene, 5-n-heptyl-2-hydroxypyrimidine 1 was obtained.
1.4 g were obtained.

28.4 g of phosphorus oxychloride was added to a mixture containing 7.2 g of 5-n-heptyl-2-hydroxypyrimidine and 1.8 g of N, N-dimethylaminoaniline obtained in the above, and the mixture was refluxed for 5 hours. After the completion of the reaction, the temperature was returned to room temperature, and the reaction solution was poured into ice water. After neutralization with sodium hydroxide, the mixture was extracted with ether. The ether layer was washed with 1N aqueous hydrochloric acid, washed with water, and then the ether was removed. The ether was dissolved in hexane and purified with a silica gel column to obtain 6.5 g of oily 2-chloro-5-heptylpyrimidine.

1.0 g of 2-chloro-5-heptylpyrimidine and pn-
Octyloxy-m-fluorophenylacetylene 1.0 g
In 30 ml of triethylamine, bistriphenylphosphine palladium dichloride (60 mg) as a catalyst, copper (I) iodide
The reaction was carried out using 15 mg and 90 mg of triphenylphosphine at a reflux temperature under a nitrogen atmosphere for 10 hours. After the completion of the reaction, triethylamine was removed and extracted with toluene. The toluene layer was washed with hydrochloric acid, washed with water, treated with a silica gel column, and then recrystallized twice with ethanol to obtain 0.38 g of the compound of No. 8 in Table 1, which is a compound of the present invention as white crystals.
I got The structure of the compound was confirmed by NMR (nuclear magnetic resonance spectrum analysis), MS (mass spectrometry), IR (infrared absorption spectrum analysis) and elemental analysis. The IR, H-NMR and F-NMR spectra of the above compound are shown in FIGS. 1, 2 and 3, respectively.

Elemental analysis: Theoretical value (%) Actual value (%) C: 76.42 C: 76.30 H: 8.73 H: 8.91 N: 6.60 N: 6.45 F: 4.48 F: 4.56 Example 2 Production of compound No. 64 in Table 1 3.4 g of 2-chloro-5-heptylpyrimidine obtained in 1 of Example 1 and 3-methyl-1-butyn-3-ol 1.
6 g of the mixture was reacted for 13 hours at reflux temperature in a nitrogen atmosphere using 40 mg of bistriphenylphosphine palladium dichloride, 25 mg of copper (I) iodide and 200 mg of triphenylphosphine as catalysts in 40 ml of triethylamine. After the completion of the reaction, triethylamine was removed and extracted with toluene. The toluene layer was washed with a 1N aqueous hydrochloric acid solution, washed with water, and then the toluene was removed and recrystallized from hexane to obtain 2.8 g of the following compound (a) as a solid.

1.7 g of powdered sodium hydroxide was added to a solution of 2.8 g of the above compound (a) in 100 ml of dry toluene.
Heated to reflux for an hour. After cooling, toluene was removed after washing with water. The obtained black oil was dissolved in hexane and separated and purified by a silica gel column to obtain 1.7 g of liquid 2-ethynyl-5-n-heptylpyrimidine.30.0 g of o-fluoro-p-iodophenol was added to 300 ml of anhydrous toluene. The mixture was dissolved, 16 ml of pyridine was added, and the mixture was stirred at room temperature. To this, 17.6 ml of benzoyl chloride was added dropwise over 15 minutes, and the mixture was stirred at room temperature for 24 hours. The reaction mixture was washed sequentially with water, 1N hydrochloric acid, a saturated aqueous solution of sodium hydrogen carbonate and water, and then toluene was distilled off. By recrystallizing the obtained solid from ethanol, 38.2 g of the following compound (b) was obtained.
I got

12.8 g of the compound (b) obtained in was dissolved in 50 ml of toluene, 25 ml of a 2M aqueous sodium carbonate solution was added, and the mixture was stirred at room temperature. Under an inert gas atmosphere, 860 mg of tetrakistriphenylphosphine palladium and 30 ml of an ethanol solution of 5.0 g of phenylboric acid were added, and the mixture was heated under reflux for 5 hours.
After allowing to cool, the reaction was stopped with 3 ml of 30% aqueous hydrogen peroxide, extracted with toluene, washed with water, and the toluene was distilled off. By recrystallizing the obtained solid from hexane, the following compound (c) was obtained.
7.0 g were obtained.

Dissolve 5.6 g of the compound (c) obtained in the above in 70 ml of acetic acid,
To this, 2 ml of sulfuric acid, 1.1 g of metaperiodic acid, and 2.4 of iodine
g was added and stirred at 90 ° C. for 10 hours. After cooling, the reaction mixture was poured into 200 ml of ice water, excess iodine was reduced with sodium bisulfite, and the precipitated solid was collected by filtration. This was recrystallized from toluene to give the following compound (d) 3.
5 g were obtained.

The compound (d) 3.5 obtained in the above was suspended in 60 ml of ethanol, 1.0 g of sodium hydroxide was added thereto, and the mixture was heated under reflux for 1 hour. After cooling, ethanol was distilled off, and the obtained solid was dissolved in 80 ml of water. Carbon dioxide gas was blown into this solution, and the precipitated solid was collected by filtration to obtain 2.4 g of the following compound (e).

2.4 g of the compound (e) obtained in the above was dissolved in 20 ml of dimethyl sulfoxide, and an aqueous sodium hydroxide solution (1.0 g
/ 10 ml) and 1.3 g of 1-bromohexane, and the mixture was stirred at 65 ° C. for 5 hours. After cooling, the reaction mixture was extracted with hexane and washed twice with water. The hexane was distilled off to obtain 2.7 g of the following compound (f).

1.5 g of the compound (f) obtained in the above and 0.8 g of the compound obtained in 50 ml of triethylamine were used as catalysts to prepare 20 mg of bistriphenylphosphine palladium dichloride and copper (I) iodide.
The reaction was carried out at room temperature for 5 hours under a nitrogen atmosphere using 5 mg. After the completion of the reaction, triethylamine was removed and extracted with toluene. The toluene layer was washed with 1N aqueous hydrochloric acid, washed with water, treated with a silica gel column, and then recrystallized twice with ethanol to obtain white crystals of the compound of the present invention.
0.97 g of the compound No. 1-64 in 1 was obtained. The IR, H-NMR and F-NMR spectra of the above compound are shown in FIGS. 4, 5 and 6, respectively.

Elemental analysis: Theoretical value (%) Actual value (%) C: 78.81 C: 78.65 H: 7.84 H: 7.65 N: 5.93 N: 6.01 F: 4.03 F: 4.12 Example 3 Production of compound No. 84 in Table 1 6-bromo-2-naphthol is converted to dimethyl sulfoxide
Aqueous sodium hydroxide (9.0 g of sodium hydroxide, 20 ml of water) was added to the solution dissolved in 300 ml, and the mixture was stirred until a uniform solution was obtained. Then n-hexyl bromide 37.0
g was added and stirred at room temperature for 3 days. 1.51 ice water
And extracted three times with hexane. After washing the hexane layer with water, hexane was removed and recrystallized from methanol to obtain 54.4 g of 2-n-hexyloxy-6-bromonaphthalene.

13.0 g of 2-n-hexyloxy-6-bromonaphthalene and 4.3 g of 3-methyl-1-butyn-3-ol obtained in
Was reacted in 150 ml of triethylamine using 120 mg of bistriphenylphosphine palladium dichloride, 30 mg of copper (I) iodide and 180 mg of triphenylphosphine as a catalyst at a reflux temperature for 6 hours under a nitrogen atmosphere. After the completion of the reaction, triethylamine was removed and extracted with toluene. The toluene layer was washed with 1N aqueous hydrochloric acid, washed with water, and then water in the toluene layer was removed. Then, 3.5 g of sodium hydroxide powder was added, and the mixture was heated under reflux for 1 hour. After cooling, toluene was removed after washing with water. The resulting black oil was recrystallized from methanol to give 6-n-hexyloxy-2-
5.6 g of ethynylnaphthalene was obtained.

In 2.0 ml of 2-n-hexyloxy-6-ethynylnaphthalene obtained in the above and 1.7 g of 2-chloro-5-heptylpyrimidine obtained in the example 1 in 60 ml of triethylamine, bistriphenylphosphine palladium dichloride was used as a catalyst.
The reaction was carried out for 6 hours at a reflux temperature under a nitrogen atmosphere using 0 mg, copper (I) iodide 25 mg and triphenylphosphine 150 mg. After the completion of the reaction, triethylamine was removed and extracted with toluene. The toluene layer was washed with 1N aqueous hydrochloric acid, washed with water, and then treated with a silica gel column.
By performing recrystallization twice, 1.05 g of the compound of No. 84 in Table 1, which is a compound of the present invention, as white crystals was obtained. I of the above compound
The R spectrum and H-NMR spectrum are shown in FIGS. 7 and 8, respectively.

Elemental analysis value: Theoretical value (%) Actual value (%) C: 81.31 C: 81.19 H: 8.41 H: 8.53 N: 6.54 N: 6.45 Example 4 Production of Compound No. 134 in Table 1 p-iodobenzoic acid 57.0 130 g of thionyl chloride was added to g, and the mixture was heated under reflux for 8 hours to prepare p-iodobenzoic acid chloride. After removing excess thionyl chloride, anhydrous toluene
Dissolved in 400 ml and cooled to below 10 ° C. The solution was stirred while blowing ammonia gas at 20 ° C. or less on the surface of the toluene solution. The resulting precipitate was filtered and dried, washed with 1N aqueous sodium hydroxide, washed with water, dried, and then recrystallized from methanol to obtain 50.6 g of p-iodobenzoic acid amide.

P-Iodobenzoic acid amide 5 in 300 ml of anhydrous dioxane
0.0 g was suspended and cooled to 10 ° C. or less.

51.0 g of trifluoroacetic anhydride was added dropwise at 20 ° C. or lower.
After the completion of the dropwise addition, the temperature was returned to room temperature and stirred for a day. The resulting red clear solution was poured into ice water. The resulting precipitate was filtered and dried, and then recrystallized from hexane to obtain 33.2 g of p-cyanoiodobenzene.

About 12 g of dried hydrogen chloride was stirred into 400 ml of absolute ethanol containing 33.2 g of p-cyanoiodobenzene while stirring.
Blow below ℃. After stirring at room temperature for 3 days, the solvent was removed and then dry ethanol containing about 30 g of anhydrous ammonia was added.
After slowly adding 00 ml under ice-cooling, the mixture was stirred at room temperature for 3 days. After removing ethanol and ammonia, anhydrous ether was added and the resulting precipitate was filtered to obtain 20.8 g of solid p-iodobenzamidine hydrochloride.

100.0 g of n-decyl alcohol was added dropwise at a temperature of 70 to 80 ° C. to 800 ml of anhydrous dimethylformamide containing 25.0 g of hydrogen peroxide (60% pure) at a rate at which hydrogen generation did not become vigorous. When the generation of hydrogen stops, return to room temperature, and add bromoacetaldehyde
5.0 g was added dropwise over 1 hour. The mixture was stirred at room temperature for 3 days. After the completion of the reaction, the mixture was poured into ice water and extracted with toluene. After washing the toluene layer with water, toluene was removed and distillation under reduced pressure was performed to obtain 58.3 g of n-decyloxyacetaldehyde diethyl acetal. (Bp; 93-94 ° C / 0.4mmH
g) 82.5 g of dry dimethylformamide was dissolved in 350 ml of anhydrous 1,2-dichloroethane and cooled to 5 ° C or lower. 56.0 g of trichloromethyl chloroformate in the solution
At 10 ° C. or lower. After completion of the dropwise addition, the mixture was further stirred for 30 minutes and then separately prepared in a solution of n-decyloxyacetaldehyde diethyl acetal in 1,2-dichloroethane (n-dichloroethane).
-Decyloxyacetaldehyde diethyl acetal 5
8.0 g, 1,2-dichloroethane 75 ml) was added dropwise. After the completion of the dropwise addition, the mixture was refluxed for 3 hours. After cooling to room temperature, add aqueous sodium hydroxide (40.0 g of sodium hydroxide, 500 ml of water) and add 30 to 50 ° C.
For 3 hours. After washing the organic layer with water, 1,2-dichloroethane was removed and distillation under reduced pressure was performed to obtain 16.8 g of β-n-decyloxy-α-dimethylaminoacrolein.

To a solution prepared from 300 ml of absolute ethanol and 2.65 g of sodium metal was added p-iodobenzamidine.
9.0 g of β-n-decyloxy-α-dimethylaminoacrolein obtained with 10.6 g of hydrochloride was added, and the mixture was heated under reflux for 18 hours. After completion of the reaction, the solvent was removed and the mixture was extracted with toluene. The toluene layer was washed with 1N aqueous hydrochloric acid, washed with water, and then toluene was distilled off.
5.1 g of iodophenyl-5-decyloxypyrimidine were obtained.

2.0 g of 2-p-iodophenyl-5-decyloxypyrimidine and 1.0 g of 1-octyne obtained in
In 40 ml, the reaction was carried out overnight at room temperature under a nitrogen atmosphere using 48 mg of bistriphenylphosphine palladium chloride and 12 mg of copper (I) iodide as a catalyst. After the completion of the reaction, triethylamine was removed and extracted with hexane. Hexane layer
After washing with 1N hydrochloric acid and washing with water and then treating with a silica gel column, the compound of the present invention of white crystals, No. 134 in Table 1, was recrystallized twice with ethanol to give the compound No. 134.
1.2 g were obtained. IR spectrum and H-NMR of the above compound
The spectra are shown in FIGS. 9 and 10, respectively.

Elemental analysis: Theoretical value (%) Actual value (%) C: 80.00 C: 79.83 H: 9.52 H: 9.65 N: 6.67 F: 6.81 Example 5 Production of compound No. 157 in Table 4 150 ml of absolute ethanol and 1.33 To a solution prepared from g of sodium metal, 5.3 g of p-iodobenzamidine hydrochloride obtained in Example 4 and 4.3 g of β-n-nonyl-α-dimethylaminoacrolein were added, and the mixture was heated under reflux for 20 hours. After completion of the reaction, the solvent was removed and the mixture was extracted with toluene. The toluene layer was washed with 1N aqueous hydrochloric acid and washed with water, and then toluene was distilled off and recrystallized from methanol to obtain 3.8 g of 2-p-iodophenyl-5-nonylpyrimidine.

0.8 g of 2-p-iodophenyl-5-nonylpyrimidine and 0.5 g of pn-hexyloxy-m-fluorophenylacetylene obtained in the above were used as catalysts in 30 ml of triethylamine and bistriphenylphosphine palladium dichloride 12 as a catalyst.
The reaction was carried out for 5 hours at room temperature under a nitrogen atmosphere using 3 mg of copper (I) and copper (I) 3 mg. After the completion of the reaction, triethylamine was removed and extracted with toluene. After washing the toluene layer with 1N aqueous hydrochloric acid, washing with water and then treating with a silica gel column,
By recrystallizing twice with ethanol, 0.43 g of the compound of No. 157 in Table 4 which is a compound of the present invention as white crystals was obtained. The IR, H-NMR and F-NMR spectra of the above compound are shown in FIGS. 11, 12 and 13, respectively.

Elemental analysis: Theoretical value (%) Actual value (%) C: 79.20 C: 79.31 H: 8.20 H: 8.07 N: 5.60 N: 5.73 F: 3.80 F: 3.65 Example 6 Production of No. 96 compound in Table-2 To 20 ml of ethanol, 0.2 g of the compound of No. 64 in Table 1 obtained in Example 2 and 10 mg of 5% palladium carbon were added, and hydrogenation was carried out at a reflux temperature and normal pressure. After confirming the disappearance of hydrogen absorption, the catalyst was removed by filtration, and the mixture was cooled to room temperature. The obtained crystals were recrystallized again with ethanol to obtain white crystals of the compound of the present invention in Table-2.
0.15 g of No. 96 compound was obtained. The IR, H-NMR and F-NMR spectra of the above compound are shown in FIG. 14, FIG. 15 and FIG. 16, respectively.

Elemental analysis: Theoretical value (%) Actual value (%) C: 78.16 C: 78.31 H: 8.61 H: 8.43 N: 5.88 N: 5.97 F: 3.99 F: 4.10 Phases of compounds obtained in Examples 1 to 6 Table 5 shows transition temperatures.
Shown in

Each symbol in Table 3 represents the following phases.

Cry; crystalline phase S ₁ ; unidentified smectic phase S _A ; smectic A phase S _C ; smectic C phase N; nematic phase Iso; isotropic liquid phase ・; phase exists −; phase does not exist (); mono The present invention provides novel smectic C liquid crystals and smectic liquid crystals useful as components of smectic C liquid crystal compositions. These smectic liquid crystals have the following remarkable characteristics.

(1) Those having no liquid crystal phase at a lower temperature side than the smectic C phase are very useful because the temperature range of the smectic C phase can be expanded by mixing.

(2) Since the compound having a two-ring structure has a high maximum temperature in the smectic C phase temperature range while having a two-ring structure, when added to a liquid crystal composition having a low maximum temperature in the smectic C phase temperature range, it does not increase the viscosity. It is very useful because the maximum temperature can be increased.

(3) Among the liquid crystal compounds of the present invention, those having a rigid acetylene bond in the skeleton have very good orientation.

(4) Also, the liquid crystal having a naphthalene ring has a good alignment property due to its rigid skeleton, and is very useful as a component for improving the alignment property of a practical liquid crystal composition even if it does not exhibit a smectic C phase itself. It is.

(5) The viscosity is lower than that of the phenylbenzoate-based smectic liquid crystal C liquid crystal.

(6) Good compatibility with other smectic C liquid crystals.

(7) Good stability against light, heat and moisture.

(8) Since the structure is very similar to that of the tolan optically active substance (tolan dopant), the compatibility with these compounds is very good.

(9) Since a liquid crystal compound having an acetylene bond has a large birefringence, it is added to not only a smectic C liquid crystal composition but also a nematic liquid crystal composition to reduce the thickness of the liquid crystal display cell and increase the response speed. You can do it.

Due to the above effects, the liquid crystal compound of the present invention is a very useful substance in developing a practical ferroelectric smectic liquid crystal composition.

[Brief description of the drawings]

FIGS. 1, 2 and 3 show the IR, H-NMR and F-NMR spectra of the compound obtained in Example 1, respectively. FIGS. 4, 5 and 6 show the compounds of the Example, respectively. 9 shows IR, H-NMR and F-NMR spectra of the compound obtained in Example 2, and FIGS. 7 and 8 show IR and H-NMR of the compound obtained in Example 3, respectively. First
FIG. 0 shows IR and H of the compound obtained in Example 4, respectively.
FIG. 11, FIG. 12 and FIG. 13 show IR, H-NMR and F-NMR of the compound obtained in Example 5, respectively.
FIG. 14, FIG. 15 and FIG. 16 show IR, H-NMR and F-NMR spectra of the compound obtained in Example 6, respectively.
-Shows an NMR spectrum.

Continuation of the front page (72) Inventor Kuniyoshi Yoshio 11 Sanyo Kasei Kogyo Co., Ltd., 11-11 Hitotsubashi-Honcho, Higashiyama-ku, Kyoto-shi, Kyoto (56) References JP-A-63-60972 (JP, A) JP-A-36365 (JP, A) JP-A-60-149562 (JP, A) JP-A-59-5162 (JP, A) WO 89/6677 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C07D 239/26 C07D 239/34 C07D 239/38 C09K 19/34 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] (1) General formula Wherein R and R ′ are an alkyl group having 1 to 18 carbon atoms;
X ₁ and X ₂ are a single bond (direct bond), -O-, -S- or-
C≡C-, m and n are 1, Y is -C≡C-, and A is a 1,4-phenylene group or a 2,6-naphthylene group which may be substituted by a fluorine atom. is there Is a pyrimidine ring A pyrimidine-based liquid crystal compound represented by the formula: