JPH03263483A - Lactic acid derivative and liquid crystal element using liquid crystal material containing same derivative - Google Patents

Abstract

NEW MATERIAL:A compound shown by formula I (R<1> is alkyl or alkoxy; R<2> is alkyl; Y is group prepared by bonding three groups arbitrarily selected from groups shown by formula II to formula IV; C* is asymmetric carbon atom). EXAMPLE:{4-[2-(4-Octyloxyphenyl)pyrimidin-5-yl]phenyl} (S)-alpha-n- butyloxypropionate. USE:A liquid crystal composition for display element. PREPARATION:5-(4-Hydroxyphenyl)-2-(4'-octyloxyphenyl)pyrimidine is suspended in methylene chloride, mixed with (S)-alpha-butyloxypropionic acid, N,N'- dicyclohexylcarboxylic acid diimide and 4-pyrrolidinopyridine and stirred at room temperature for 6 hours. Then the precipitated crystal is filtered off, the filtrate is concentrated under reduced pressure to give crude white product, which is further passed through a silica gel column and extracted with a mixed solution of n-hexane/ether.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a novel lactic acid derivative and a liquid crystal element using a liquid crystal material containing the same.

(Prior Art) Liquid crystal elements are widely used in electro-optical devices such as watches, calculators, displays for personal computers, and displays for word processors. However, the currently used nematic liquid crystal has a slow electro-optic response time of 100 to 200 msec, making it inferior to plasma displays and the like, and its use in fields requiring high-speed response is limited.

On the other hand, liquid crystal elements using ferroelectric liquid crystals are known to exhibit high-speed response on the microsecond scale (N, A).

C1ark: Δapplied Phys, 1. eit,
, 3G, 809 (1980). ) It is expected that its practical application will not lead to a dramatic expansion of the applications of liquid crystal elements.

The ferroelectric liquid crystal uses the chiral smectic C phase (hereinafter abbreviated as Sc* phase), and the liquid crystal material has chemical stability, the appearance of O8c main phase 0 at a wide range of temperatures including room temperature, and good properties. Various properties such as orientation and high-speed response are required.

However, at present, it is difficult to obtain a liquid crystal material with a single composition of ferroelectric liquid crystal that satisfies the above characteristics and can be put to practical use. Similarly, in ferroelectric liquid crystals, attempts have been made to obtain the desired characteristics of -C by mixing several types of compounds.

As one method of mixing such ferroelectric liquid crystals, a method is known in which an optically active substance is added to a compound having an Sc phase that does not exhibit ferroelectricity to induce an Sc* phase. (W. Kuezynski et al. Chel
! 1°Phys, 1. ,et,t,,70.123
See (1,980). ) In this method, various physical properties of the ferroelectric liquid crystal (spontaneous polarization value Ps, Bitge=, Sc*
Temperature range of phase, tilt angle, bending 4'J1 index, anisotropy〇,
(viscosity, etc.), Ps and pitch can be easily controlled by adjusting the jll of the optically active substance added, and the Sct phase temperature range can be expanded by adjusting the compound having the Sc phase, which is the main component in the mixed components. This is iiJ Noh.

(Problems to be solved by the invention 1 and 2) However, in such a mixing method in which the Sc* phase is induced by adding an optically active substance, the selection of the optically active substance to be added is important. Ru.

For example, S
Adding a large amount to a compound having c phase1. In this case, the temperature range of the induced Sc* phase decreases rapidly, and in extreme cases, the problem arises that the Sc* phase no longer appears.

On the other hand, if the amount added is small, the influence on the Sc* phase temperature range will be small, but on the contrary, various properties important for a ferroelectric liquid crystal, such as responsiveness, will become insufficient.

Furthermore, optically active substances also have a significant effect on tilt angles.

That is, when a ferroelectric liquid crystal is applied to a birefringent liquid crystal display element, the contrast is highest when the tilt angle is 22.5°. However, some optically active substances exhibit a tilt angle of only about 10'', and a liquid crystal display element containing this in a liquid crystal material causes a significant decrease in contrast.

Therefore, an optically active substance added to induce an Sc* phase in a compound having an Sc phase that does not exhibit ferroelectricity (2) a compound that has liquid crystallinity in the SC* phase temperature range; (7) It is preferable to use a substance that potentially has liquid crystal properties, and it is desirable to use a substance that exhibits good properties of ferroelectric liquid crystal, such as response time and tilt angle, when mixed.

The present invention has been made to solve these problems.When mixed with a compound that exhibits white Sc phase or SC1* phase, ferroelectric liquid crystal and 1. The purpose of the present invention is to provide a solution using a lactic acid derivative and a liquid crystal material containing the lactic acid derivative, which is useful for obtaining the various properties necessary for the invention.

[Structure of the Invention] (Means for Solving the Problems) The lactic acid derivative of the present invention is characterized by being represented by 0CI(3 (wherein, R1 represents an alkyl group or an alkoxy group), ing.

Further, the liquid crystal element of the present invention has at least one transparent element.
It is characterized in that a liquid crystal material containing a lactic acid derivative represented by the above formula (1) is sandwiched between a pair of substrates.

Such a lactic acid derivative represented by the formula (1), for example, can be produced by the synthetic route shown below.

Synthetic route 1? -1'-01 (...(I)Hoc-ano
, cR2 ... (b) CH30 or its reactive derivative ↓ Esterified CH3 In the above synthetic route, R in the formula is a bond of three groups arbitrarily selected from the group consisting of and C represents an asymmetric carbon atom.

Furthermore, the raw material compound for synthesizing the lactic acid derivative of the present invention can be produced by the following synthetic route. In addition, in the following formula, Rb represents a hydroxy protecting group such as a benzyl group, and Ra represents an alkyl group.

Other raw material compounds can also be produced based on the above raw material synthesis route.

The alkyl group R1 of the lactic acid derivative represented by formula (I) of the present invention is a linear or branched alkyl group having 1 to 20 carbon atoms, such as a methyl group, an ethyl group, a propyl group, a butyl group, or a pentyl group. Examples include hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, and dodecyl group.

Furthermore, the alkoxy group of R1 has 1 to 2 carbon atoms.
Examples include a group having 0 straight-chain or branched alkyl groups as an alkyl moiety.

The alkyl group R2 in the lactic acid derivative of the present invention has 1 to 1 carbon atoms, as in the alkyl group R1 described above.
Twenty straight or branched alkyl groups are mentioned.

Furthermore, the Y group of the lactic acid derivative of the present invention is
The lactic acid derivative of the present invention has a molecular structure similar to that of a liquid crystal compound and has a large intramolecular dipole moment bias. The fundamental characteristics (pitch, response time, tilt angle, etc.) of the ferroelectric liquid crystal can be improved without significantly affecting the transition temperature of the ferroelectric liquid crystal phase and the set phase.

Furthermore, the SC phase and the liquid crystal phase, which is on the high temperature side,
That is, there is little influence on the phase transition temperature of the (chiral) nematic phase and smectic A phase, and it is possible to improve the orientation as well as the pitch.

(Example) The present invention will be explained below with reference to Examples.

Example 1 (S)-α-n-butyloxypropionic acid [4-+2
-(4-octyloxyphenyl)pyrimidin-5-yl)phenyl] 5-(4-hydroxyphenyl) -2-(4'-octyloxyphenyl)pyrimidine (0.5 g) was suspended in methylene chloride (20 ml). , to which (S)-α-butyloxypropionic acid (0.28 g), N,N'-
Dicyclohexylcarbodiimide (0.36g), 4
- Add pyrrolidinopyridine (40 mg) and leave at room temperature for 6 minutes.
Stir for hours.

] 0 Filter out the precipitated crystals. The filtrate was condensed under reduced pressure to obtain a white crude product. Add this to silica gel horn; Tsumu ni Kikaku L2, Rohe Keirin Ether mixture C solution 1
．． White crystals (0,
42g) was obtained.

IR (Nujol): 1770, IGoo, 15
80.1430.1250.1160.1.120 (J
-' Mass m/z + 504 (M") NMR (
CDCI3) δ: 0.88~・1.86 (251
1,m), 3.4[i-3,57(1,11,m),
3. (i [i ~3.77 (111, m), 4.04 (
2+1. t, J-7Hz), 4.22 (111,q, J
-711z), 7.01 (2H, d, J-9ttz),
7.28 (211, d, J-9Hz), 7.83 (2H
, dl-9Hz), 8.42 (2H, d, J=91tz
), 8.95 (21(,S) Example 2 (S)-α-lobobyloxypropionic acid [4−+2
-(4-nonyloquin-phenyl)pyrimidin-5-yl)phenyl] In the same manner as in Example 1, the compound -(-U- was obtained.

IR (Nujol): 1770.1600.15
80.1430.1200, 1 1160, l 1.15 (IJ"'Mass m
/z: 518 (M”) NMR (CDCI
3) δ: 0. H~1.85 (27H, m), 3
．． 4G ~ 3.57 (111, m), 3.66 ~ 3.77
(ilt, m), 4.04 (2+1.tl-7112)
, 4.22 (ltl, q, J-7iiz), 7.01 (
2tl, d, j-911z), 7.21i (2H, dl
-911z), 7.63 (2H, di-9Hz), 8,
42 (21-1, d, J-9+1z), 8°94 (2H
,S) Example 3 (S)-α-n-hexyloxypropionic acid [4-[
2-(4-octyloxyphenyl)pyrimidine-5
-yl)phenylco In the same manner as in Example 1, the compound described above was obtained.

IR (Nujol) + 17 [io, 1600.1
580.1430.1250゜1160.1.1.20
-' Mass m/z: 532 (M") NMR (
CDCI3) δ: 0.86-1. ．． 86 (29H, m
), 3.45~3.58 (ill, m), 3.65~
3.7[i(+,tl,i), 4.04(21+,t,
J-7Hz), 4.22 (lIt, q, J-71Iz)
,7.01(2H,d,J-9Hz>,7.2[1(2
H, d, J-911z), 7. [13(21(, dJ
-911z), 8.43 (2H, d, J-91fz),
8.95(2+1.S)] 2 Example 4 (S)-α-n-butyloxypropionic acid [4i5-
(4-octyloxyphenyl)pyrimidin-2-yl)phenyl] In this example, a synthesis example of a starting compound was first described, and then the synthesis was performed using the obtained starting compound [)
Describe the synthesis of target compounds.

4-1> Synthesis of raw material compound 2-<4-penzyloxyphenyl)-5-(4-hydroxyphenyl)pyrimidine 4-penzyloxytubonylamine synthesized by a conventional method using p-cyanophenol as a raw material 3.2 g of zinc) and 4-hydroxyphenylacetic acid according to a conventional method. 3-dimethylamino-2-di-4-hydroxyphenyl)-2-propen-1-al (2,98 g) was dissolved in pyridine (10 ml) and stirred at 17.70°C for 20 hours.

Pour the reaction solution into ice water and acidify with hydrochloric acid.
The resulting crystals were collected by filtration and recrystallized with ethanol.
Pale red crystals (3.25 g) of benzyl Aginfur)-5-(4-hydroxyunit 1'3)pyrimidine were obtained.

JR (Nujol): 1800.1575.15
10, +270.1250.1230, t i e o
-'Mass m/z: 354(M'')<4-2
> Synthesis of raw material compound 2-(4-hydroxyphenyl)-5-(4-0-octyloxyphenyl)pyrimidine 2-(4-benzyloxyphenyl)-5-(4-) obtained in <4-1> above hydroxyphenyl)pyrimidine (3
A dimethylformamide solution of 60% sodium hydride (0.44 g) was gradually added dropwise to a dimethylformamide suspension of 60% sodium hydride (0.44 g) under water cooling.

After stirring at room temperature for 1 hour, the mixture was cooled on ice again, and -octyl bromide (1.95 g) was added over about 20 minutes, followed by stirring at room temperature for 2.5 hours. The reaction solution was poured into ice water and extracted twice with methylene chloride. The organic layer was washed with water, dried over magnesium sulfate, and the solvent was distilled off under reduced pressure (2.0 g) to obtain a white crystalline residue (4.08 g).

This was mixed with tetrahydrosolane-ethanol mixed solvent (1,
/l) and 1.10% Pd-C after nitrogen substitution.
(0.54 g) was added, and catalytic reduction was carried out under a hydrogen pressure of 2 to 3 atm.

After filtering off the catalyst, the filtrate was concentrated under reduced pressure to obtain a yellow solid residue. This was recrystallized from ethanol and 2-(4-
<2.7 g of pale yellow crystals of hydroxyphenyl)-5-(4-n-octyloxyphenyl)pyrimidine were obtained.

IR (Nujol): 3400.3150.11
300.1575.1425, I280.1240.1
170.1180-'Mass m/z: 37
8(M”)NMR(CDCI3)δ: 0.8
6-1.86 (15) 1. m) ,4.01(2H,1
l-7Hz), 6.93 (2H, d, J-9Hz), 7
．． 03 (2H, d.

J-911z), 7.53 (2H, d, J-9Hz),
8.35(2)1. d, J-9t(z), 8.94(2
H, S) <4-3> Synthesis of lactic acid derivative (S)-α-n-butyloxypropionic acid [4-+5
-(4-octyloxyphenyl)pyrimidin-2-yl)phenylco A lactic acid derivative was obtained in the same manner as in Example 1 using the raw material compound obtained in <4-2> above.

5 IR (Nujol): 1750.1600.15
80.1510.1430.1280.1240-'Mass m/z: 504 (M") NMR
(CDCI3)6: 0.86 ~ 0.98 (
911, Ill>, 1. , 30-1.80 (LBH,
m), 3.46-3.57 (IH, m), 3. fi
7-3.78 (1, H, tn), 4.00 (2H, t
, J-711z), 4.22 (LH, q, J-month tz)
, 7.04(2)1. d, J-9Hz), 7.25(2
H, d, J-9Hz), 7.55 (2H, d, J=9H
z), 8.52 (2H, d, J-9Hz), 8.97 (
211,S) Example 5 (S)-α-n-butyloxypropionic acid [4-+4
'-(5-octylpyrimidin-2-yl))biphenyl]<5-1> Synthesis of raw material compound 2-[4-(4'-benzyloxy)biphenylyl]-
5-octylpyrimidine 4-(4'-benzyloxy)biphenylamidine hydrochloride (2°Og) synthesized from 4-cyano-4'-hydroxybiphenyl according to a conventional method and 3-N,N'-dimethylamino-2 - Octyl acrolein (1.8 g), sodium (1.8 g) and anhydrous methanol (100 g)
The mixture was heated under reflux for 20 hours in a methanol solution of sodium methylate prepared from (ml).

After cooling, the reaction solution was acidified with hydrochloric acid to obtain a crude product. After suspending this in ethyl acetate and filtering it, 2-[4
-(4'-benzyloxy)biphenylyl]-5-octylpyrimidine (2.0 g) was obtained.

NMR (CDCI3) δ: 0.81-0.95
(3)1. m), 1.16 to 1.48 (IOH, Iri
, 1.55-1.74 (2H, m), 2.83 (2H,
L.

J-7)lz), 5.12(2H,S), 7.0
7 (2H, d, J-8Hz), 7.33-7.48 (5
H, m), 7.59-7.70 (4H, m), 8.45
(2H, d.

J-8tlz), 8. fli3(211,3)<
5-2> Synthesis of raw material compound 2-[4-(4'-hydroxy)biphenylyl]-5
-Octylpyrimidine 2-[4-(4'-benzyloxy)biphenylyl]-5-octylpyrimidine (1,
, 9g) of tetrahydrofuran-ethanol (3:1)
Solution (160 ml) was added with 10% palladium-carbon (0
, 10 g) was added, and medium pressure reduction was performed under 2.5 atm hydrogen.

After removing palladium-carbon by filtration, solvent 7 was distilled off under reduced pressure to obtain a composition product. This was applied to a silica gel column and eluted with a mixed solvent of n-hexane-chloroform-ethyl acetate to obtain 2-[4(4'-hydroxy)biphenylyl]-5-octylpyrimidine (1.3 g).

IR (Nujol): 1240.1427.14
92.1523, I564.1585.3360 ”' Mass m/z: 380 (M”) NMR (
CDCI3) δ: 0.82-0.93 (311,
m), 1.18 to 1.43 (10H, l1l),
1.58-180 (211, m), 2.64 (2H,
t.

J=7Hz), 6.92 (2H, d, J-9Hz), 7
．． 26 (LH, S), 7.55 (2H, d, J-9Hz
), 7.86 (2H, d, J-9H2), 8.44 (2
8, dJ-9Hz), 8.84 (2H, S) <5-3> Synthesis of lactic acid derivative (S)-α-n-butyloxypropionic acid [414'
(5-Octylpyrimidin-2-ylbiphenyl) The above lactic acid derivative was obtained in the same manner as in Example 1 using the raw material compound obtained in <5-2> above.

IR (Nujol): 1115.1.764-
'Mass m/z: 4H (M'') 8 NMR (CDCI 3) δ: 0.85
~0.98 (Oil, m), 1.28 ~ 1.73 (19
! 1. m), 2. [13(211,t, J-711z
), 3.4G to 3.5G (1,11,m), 3.6f'
i = 3.77 (111, m), 4.21 (Ill, q
, J-711z), 7.20(211,d, l-811
z), 7.88 (21!, d, J-811z), ? , [
19 (211, dlJllz), 8.49 (2H, d,
J-811z), 8, 84 (2+1, S) Elemental analysis 3] 40 N2 03 calculated value [%1 7B
, 19 8,25 5.73 9.82 experimental value L%]
75.94 8,03 5.59 In the above-mentioned Examples, -C'0 compounds [Lactic acid derivatives are also summarized in Table 1].

(Table 1) 90 Next, an example will be described in which a liquid crystal material containing the lactic acid derivative was prepared and a liquid crystal element was manufactured.

Example 6 A liquid crystal composition (A) was prepared by mixing equimolar amounts of three types of compounds represented by the following structural formula.1. Ta.

Although this liquid crystal composition (A) has a phase transition temperature not shown in (-), it is not a highly conductive liquid crystal composition because it is composed of a non-optically active substance.

C-2°C, 5e53°C, 5A65°C, N69°C, Is.

Next, OC1 obtained in Example 1 of the present invention and expressed by the following formula
+3 (in the formula, the (S) appended to C indicates that the asymmetric carbon atom r has the S-absolute configuration) to 100% by weight of the liquid crystal composition represented by the above formula (A). A liquid crystal material (A-1, ) was prepared by adding 5% by weight of [2].

When the phase transition temperature of this liquid crystal material (A-1) was measured using a polarizing microscope under the temperature decreasing condition F of 5° C./min, the following results were obtained.

C<10℃, Se$55℃, 5A68℃, N*71℃
, Is.

In this way, the liquid crystal material (A-1) was a ferroelectric liquid crystal material in which the Sc, * phase appeared in the region including the strained part. I assembled the liquid crystal cell as shown in the diagram.

First, as shown in FIG. 1, a transparent electrode 3.4 is formed on a glass substrate 1.2, and a polyimide face is applied to the surface.
After rubbing the surface 2 to form an alignment layer 5.6,
This glass substrate 1.2 was held with rubbing layers facing each other at intervals of 2 μm, and the above-mentioned liquid crystal material (A-1) was filled between them to create a liquid crystal cell. 7 is a sealing material. Two polarizing plates 8.9 were placed on the sides of this liquid crystal cell, and when an electric field was applied while the temperature was maintained at 25°C, two states were displayed depending on the polarity of the electric field. I was able to confirm that. The response time at this time is for voltage application of ±IOV,
It was t5osec. Also, the angle between the two states is 35°
Met.

Furthermore, since it had both the N* phase and the SA phase on the high temperature side of the Sc* phase, it had excellent orientation, and monodomains could be easily formed over the entire orientation region.

Example 7 Similar to Example 6, the actual OC1+ of the present invention expressed by the following formula
3 is 100% by weight of the liquid crystal composition represented by formula (A) above.
5% by weight was added to the liquid crystal material (A-2) to prepare a liquid crystal material (A-2).

The phase transition temperature of this liquid crystal material (A-2) was measured by
When carried out under the same conditions as in Example 6, the following results were obtained.

C<10℃, S cH5℃, S to 68℃, N*71℃
, Is.

3 Furthermore, a liquid crystal cell similar to that in Example 6 was prepared using the liquid crystal material (A-2), and the response time to voltage application of ±IOV at room temperature was measured.
It was c. Moreover, the angle between the two states was 35°.

Example 8 Similarly to Example 6, the present invention C113 represented by the following formula (in the formula, (S) appended to C indicates that the asymmetric carbon atom is in the S-absolute configuration ) was added in an amount of 5% by weight to the liquid crystal composition represented by the above formula (A) to prepare a liquid crystal feed (A-3).

The phase transition temperature of this liquid crystal material (A-3) was measured by
When carried out under the same conditions as in Example 6, the following results were obtained.

c < io℃, S c*54℃, 5A88℃, N*7
1°C, Is.

Furthermore, a liquid crystal cell similar to that of Example 4 v'J6 was prepared using the above liquid crystal material (A-3), and the response time to voltage application of ±IOV at room temperature was measured and found to be 210 μsec. Also, the angle between the two states is 37
"Met.

As is clear from the above results, when the lactic acid derivative of the present invention is mixed with other liquid crystal compositions, it has almost no effect on the transition temperature of the Sc phase and SC* phase, and has various properties as a ferroelectric liquid crystal. We were able to improve the characteristics.

Furthermore, a liquid crystal phase that is on the higher temperature side than the Sc phase and SC* phase,
In other words, it was possible to obtain a liquid crystal element that had little influence on the transition temperature of the (chiral) nematic phase and smectic human phase and was also excellent in terms of orientation.

[Effects of the Invention] As explained above, when the lactic acid derivative of the present invention is mixed with other liquid crystal compositions to prepare a liquid crystal material, a liquid crystal material with excellent properties as a ferroelectric liquid crystal can be obtained. be able to.

Therefore, a liquid crystal element using a liquid crystal material containing a lactic acid derivative of the present invention has high-speed response and high orientation, and can be widely used as a display device for electro-optical devices and the like.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a liquid crystal element according to an embodiment of the present invention. 1.2...Glass substrate 3.4...Transparent electrode 5.6...Alignment layer 7...・Sealing material 8.9・・・・・・Polarizing plate

Claims (2)

[Claims] (1) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R^1 is an alkyl group or an alkoxy group, R^
2 is an alkyl group, and Y is arbitrarily selected from the group consisting of ▲ has a mathematical formula, chemical formula, table, etc. ▼, ▲ has a mathematical formula, chemical formula, table, etc. ▼, and ▲ has a mathematical formula, chemical formula, table, etc. ▼ A group formed by combining three groups, also C^*
indicates an asymmetric carbon atom. ) is a lactic acid derivative represented by (2) There is a general formula ▲ mathematical formula, chemical formula, table, etc. between a pair of substrates, at least one of which is transparent ▼ (In the formula, R^1 is an alkyl group or an alkoxy group, R^
2 is an alkyl group, and Y is arbitrarily selected from the group consisting of ▲ has a mathematical formula, chemical formula, table, etc. ▼, ▲ has a mathematical formula, chemical formula, table, etc. ▼, and ▲ has a mathematical formula, chemical formula, table, etc. ▼ A group formed by combining three groups, and C represents an asymmetric carbon atom. ) A liquid crystal element comprising a liquid crystal material containing a lactic acid derivative represented by: