JPH01106871A - Optically active compound, liquid crystal composition and electro-optical element - Google Patents

Abstract

NEW MATERIAL:The optically active compound of formula I (R<1> is 1-20C alkyl or alkoxy; R<2> is 1-20C alkyl, acyl or alkoxyacyl; X is asymmetric carbon). EXAMPLE:2-[4-(2-Butyloxypropyloxy)phenyl]-5-(4-propylphenyl)pyrimidine. USE:Useful as a component of a liquid crystal composition. It is a ferroelectric liquid crystal material giving a ferroelectric liquid crystal temperature region. It has an action to remarkably increase the spontaneous polarization and is applicable as a material to give a display with quick response. A chiral nematic liquid crystal composition produced by adding the compound to a nematic liquid crystal composition is useful as a pitch-controlling agent. PREPARATION:The compound of formula I can be produced from p- alkylphenylacetic acid of formula II via several steps such as reaction with phosphorus oxychloride, dimethylformamide and a perchlorate.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel organic compound and a liquid crystal composition containing the same, and more specifically, to an optically active compound having an optically active group and an optically active compound containing the same. The present invention relates to a liquid crystal composition and an electro-optical element using the same.

[Conventional technology]

Liquid crystal display elements have excellent characteristics such as low voltage operation, low power consumption, and the ability to display thin displays, so they are widely used as display elements in various products such as watches, calculators, televisions, and computer terminals. It is used.

Currently, the TN (twisted nematic) type display system is the most widely used display element, but its response speed is inferior to light-emitting display elements such as electroluminescence and plasma displays. Although various attempts have been made to improve this point, no significant improvement has been achieved.

However, new display systems using ferroelectric liquid crystals, which have been actively researched recently, have the potential to significantly improve response speed. (C1ark et al., 8 ppl
ied Phys, Lett,, 36.899 (1
980)). This display method uses chiral smectic C phase (hereinafter abbreviated as Sc" phase) exhibiting ferroelectricity, or other smectic phases, such as chiral smectic F phase.
, G, H, I phases, etc., and can achieve a response several hundred to several thousand times faster than a TN display element, and can achieve memory effects due to bistability, making it possible to display videos. It is expected that it will be applied to a wide variety of fields, including large-scale televisions and high-speed optical shutters.

[Problem that the invention seeks to solve]

However, despite these excellent properties, currently known compounds have not yet shown sufficient high-speed response. This is because a compound with a sufficiently large spontaneous polarization value in a ferroelectric liquid crystal phase is not known. It is known that there is a proportional relationship between the spontaneous polarization value and the response speed, and that increasing the spontaneous polarization value is the first step in obtaining high-speed response. No compound has been found yet.

An object of the present invention is to provide an optically active compound having characteristics suitable for the above-mentioned display system, which has been recently researched, and in particular has a large spontaneous polarization value necessary for realizing high-speed response.

[Measures to solve problems]

The present invention is based on the following formula (in the above formula, R1 represents an alkyl group or alkoxy group having 1 to 20 carbon atoms, and R2 represents an alkyl group, acyl group, or alkoxyacyl group containing 1 to 20 carbon atoms. , * indicates that the carbon atom is an asymmetric carbon), and a liquid crystal composition containing at least one thereof.

The compounds of the present invention do not necessarily exhibit a ferroelectric liquid crystal phase, but when used as a component of a ferroelectric liquid crystal composition, they have the effect of significantly increasing the spontaneous polarization value, and as a result, , it is possible to significantly increase the response speed. As will be described later in the Examples, by adding several to several tens of weight percent to a liquid crystal composition exhibiting a non-chiral smectic C phase that does not exhibit a spontaneous polarization value, a significantly large spontaneous polarization value is induced in the composition, and as a result, For example, as described in Example 4, 40μ at 15℃
It is possible to obtain a composition exhibiting an extremely fast response speed of sec.

This is because the response speed of the compounds described in Japanese Patent Application No. 132,800/1982 and Japanese Patent Application No. 103,977/1982, which have the highest response speed among currently known compounds, under the same conditions. 48 μsec, 12
Considering that it is 5 μSec, this is a surprising characteristic.

Further, since the compound of the present invention has an optically active carbon atom, it has the ability to induce a twisted structure by adding this compound to a nematic liquid crystal. A nematic liquid crystal with a twisted structure, that is, a chiral nematic liquid crystal, has a so-called reverse twist domain of a TN type display element.
Since the compound of the present invention does not generate a main L/ma pattern), it can also be used as an inhibitor of reverse twist domain formation.

Furthermore, the pitch of the chiral nematic liquid crystal added with the compound of the present invention is, for example, as shown in Example 5,
When 1% by weight was added to ZLI-1132 manufactured by Merck & Co., Ltd. and measured, it was as short as 10.91 seconds at 25°C, making it easier to obtain the required pitch with a smaller amount of addition, and making it easier to adjust the pitch of chiral nematic liquid crystal compositions. It can be said that it is very useful as a drug.

Further, its temperature characteristics are very good, and the temperature characteristics σ2 expressed by the following formula % is extremely flat at −0,017. (at t+=20°C, tz=70°C).

This means, for example, that the σ2 of S-4-(2-methylbutyl)-4'-cyanobiphenyl, a pinch adjuster for chiral nematic liquid crystal compositions which is well known at present, is 0.
Considering that it is 584, this can be said to be a surprising characteristic.

Next, a method for producing the compound of formula (1) will be described.

The compound of formula (1) can be suitably produced, for example, by the following route.

(VI) (■) Compound (■) (In formula (■), R2 is an alkyl group) Compound (
■) (In formula (I), R2 is an acyl group) Compound (■
) (In formula (■), R2 is an alkoxyacyl group)
.

(However, in the above formula, R1 represents an alkyl group or an alkoxy group, R represents an alkyl group, Ro represents a divalent hydrocarbon, and A represents a protecting group such as a benzyl group or a methyl group). .

That is, p-alkylphenylacetic acid or p-alkoxyphenylacetic acid (If) is reacted with phosphorus oxychloride, dimethylformamide, and then perchlorate to obtain (III). This is treated with p-substituted benzamidine chloric acid under basic conditions to obtain (TV).

This product was subjected to a deprotection reaction to obtain (V), and then treated with 2-tetrahydropyranyloxy-1-(p-)luenesulfonyloxy)propane described in Japanese Patent Application No. 132,800/1980 to obtain (Vl). Obtained. Furthermore, deprotection reaction was performed under acidic conditions to obtain (■). This product is reacted with various alkyl halides under basic conditions, and among the compounds of formula (1), those in which R2 is an alkyl group are also reacted with various fatty acids or various alkoxyalkanoic acids, In formula (1), R2 is an acyl group or an alkoxyacyl group.

Among the compounds of the present invention obtained as described above and exhibiting excellent responsiveness, representative compounds of the compounds of the present invention will be specifically shown below.

2-(4-(2-butyloxypropyloxy)phenyl)-5-(4-propylphenyl)pyrimidine, 2-(4-(2-hexanoyloxypropyloxy)phenyl)-5-(4-propylphenyl) ) pyrimidine, 2- (4-(2-(1-methylheptanoyloxy)
propyloxyphphenyl) -5-(4-propylphenyl)pyrimidine, 5-(4-propylphenyl)-2-(4-(2-(2
-pentyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 5-(4-propyloxyphenyl) -2-[4-(2-pentanoyloxypropyloxy)phenyl]pyrimidine, 2-(4-(2-( 2-Butyloxypropionyloxy)propyloxyphenyl)-5-(4-propyloxyphenyl)pyrimidine, 5-(4-butylphenyl)-2-(4-(2-butyryloxypropyloxy)phenyl)pyrimidine , 5-(4-butylphenyl)-2-(4-(2-pentanoyloxypropyloxy)phenyl]pyrimidine, 5-(4-butylphenyl')-2-(4-(2-(2
-butyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 5-(4-butyloxyphenyl)-2-(4-(2-
pentyloxypropyloxy)phenyl]pyrimidine, 5-(4-butylphenyl")-2-(4-(2-hexyloxypropyloxy)phenyl]pyrimidine, 5-(4-butyloxyphenyl")-2-( 4-(2
-(1-methylpentanoyloxy)propyloxyphenyl)pyrimidine, 5-(4-butyloxyphenyl)-2-(4-(2-
(2-Butyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 2- (4-(2-hexyloxypropyloxy)phenyl)-5-(4-pentylphenyl)pyrimidine, 2- (4-(2- (3-methylhexanoyloxy)
propyloxyphphenyl) -5-(4-pentylphenyl)pyrimidine, 5-(4-pentylphenyl")-2-(4-C2-(
2-pentyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 2-4-(2-pentanoyloxypropyloxyphenyl)-5-(4-pentyloxyphenyl)pyrimidine, 2-(4-C2-(2- butyloxypropionyloxy)propyloxyphphenyl)-5-(4-pentyloxyphenyl)pyrimidine, 2-(4-(2-butyryloxypropyloxyphenyl)-5-(4-
hexylphenyl)pyrimidine, 2-(4-(2-(2-propyloxypropionyloxy)pro-ruoxy]phenyl)-5-(4-hexylphenyl)pyrimidine, 5-(4-hexyloxyphenyl') ) -2-(4-(2-propyloxypropyloxy)phenyl] pyrimidine, 5-(4-hexyloxyphenyl") -2-(4-
(2-(1-methylhexanoyloxy)propyloxyphphenyl)pyrimidine, 5-(4-hexyloxyphenyl") -2-(4-
(2-(2-pentyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 2-(4-(
2-Butyloxypropyloxy)phenyl)-5-(
4-hebutylphenyl)pyrimidine, 5-(4-hebutylphenyl)-2-(4-(2-(1
-methylheptanoyloxy)propyloxyphphenyl)pyrimidine, 5-(4-hebutylphenyl)-2-(4-(2-(2
-pentyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 5-(4-hebutyloxyphenyl) -2-(4-(2-pentanoyloxypropyloxy)phenyl]pyrimidine, 2-(4-C2-( 2-Butyloxypropionyloxy)propyloxyphphenyl)-5-(4-pentyloxyphenyl)pyrimidine, 2-(4-(2-hexanoyloxypropyloxy)phenyl)-5-(
4-octylphenyl)pyrimidine, 2-4- (2-(2-hexyloxypropionyloxy)propyloxyphphenyl-5-(4-octylphenyl)pyrimidine, 5-(4-octyloxyphenyl) -2- (4-(
2-pentyloxypropyloxy)phenyl] pyrimidine, 2-(4-(2-(3-methylheptanoyloxy)propyloxyphphenyl) -5-(4-octyloxyphenyl)pyrimidine, 2-(4-( 2-(2-heptyloxypropionyloxy)propyloxyphphenyl)-5=(4-octyloxyphenyl)pyrimidine, 2-C4-(2-
butyloxypropyloxy)phenyl) -5-(4
-nonylphenyl)pyrimidine, 5-(4-nonylphenyl)-2-(4-(2-pentanoyloxypropyloxy)phenyl]pyrimidine, 2-(4-(2-heptanoyloxypropyloxy)phenyl)- 5-(4-nonylphenyl)pyrimidine, 2- (4-(2-(1-methylbutyryloxy)propyloxyphphenyl) -5-(4-nonylphenyl)pyrimidine, 2- (4-(2- (3-methylhexanoyloxy)
propyloxyphphenyl) -5-(4-/nylphenyl)pyrimidine, 5-(4-nonylphenyl)-2-(4-(2-(2-
propyloxypropionyloxy)propyloxy)
phenyl)pyrimidine, 2-(4-(2-(2-butyloxypropionyloxy)propyloxyphphenyl)-5-(4-nonylphenyl)pyrimidine, 5-(4-decylphenyl)-2-(4- (2-hexyloxypropyloxy)phenyl]pyrimidine, 5-(4-decylphenyl)-2-(4-(2-(2-
pentyloxypropionyloxy)propyloxyphphenyl)pyrimidine, 2-(4-(2-hexanoyloxypropyloxy)phenyl)-5-(4-decyloxyphenyl)pyrimidine, 2-(4-(2-hexanoyl) oxypropyloxy)phenyl)-5-(4-undecylphenyl)pyrimidine, 2-(4-(2-propyloxypropyloxy)phenyl)-5-(4-undecyloxyphenyl)pyrimidine, 2-(4 -(2-(2-propyloxypropionyloxy)propyloxyphphenyl)-5-(4-undecyloxyphenyl)pyrimidine, 2-(4-(2
-butyloxypropyloxy)phenyl) -5-(
4-dodecylphenyl)pyrimidine, 2-(4-(2-(2-butyloxypropionyloxy)propyloxyphenyl)-5-(4-dodecylphenyl)pyrimidine, 2-(4-(2-butyryloxy) propyloxy)phenyl)-5-(4-dodecyloxyphenyl)pyrimidine, 2- (4-(2-pentyloxypropyloxy)phenyl)-5-(4-)lysosylphenyl)pyrimidine, 2- [4- (2-(2-pentyloxypropionyloxy)propyloxyphenyl)-5-(4-tridecylphenyl)pyrimidine, 2-(4-(2-pentanoyloxypropyloxy)phenyl)-5-(4
-tridecyloxyphenyl)pyrimidine.

〔Example〕

Hereinafter, the compound of formula (I) of the present invention will be explained in more detail with reference to Examples.

Example l 5-5-(4-butylphenyl)-2-(4-(2-
Pentanoyloxypropyloxy)phenyl]pyrimidine: (In formula (I), R1 is C4Hq-1R2 is 10
Production of 〇aHq) To 366 g of dimethylformamide, add 46 g of phosphorus oxychloride.
0 g was added dropwise at 0°C, and then 1 p-butylphenyl acetic acid was added.
76.4 g were added portionwise at a temperature of -10°C. The mixture was heated at 20°C for 1 hour, at 60°C for 2 hours, and at 80°C for 5 hours.
Stir for hours. Dimethylformamide is distilled off in vacuo,
A saturated solution of magnesium perchlorate was mixed with the residue at -10°C. The precipitated crystals were collected by filtration and washed with ether to obtain 205.1 g of salt. The melting point was 102.1-102.5°C.

A mixture of 200 g of this salt, 135 g of p-benzyloxybenzamidine hydrochloride, 46 g of sodium methylate, and 21 g of ethanol was stirred under reflux for 8 hours.

Toluene was added, washed with alkali, then washed with water, the solvent was distilled off, and the residue was recrystallized from a mixed solvent of ethanol and toluene to give 2-(4-benzyloxyphenyl)-
126 g of 5-(4-butylphenyl)pyrimidine was obtained. This material exhibited liquid crystallinity, and the phase transition point was as follows.

2-(4-benzyloxyphenyl)-5-(4-butylphenyl)pyrimidine 120 g, palladium activated carbon 1
A mixture of 85 g of ethylamine, 41 g of ethanol, and 11 g of ethyl acetate was stirred under a hydrogen stream. After removing the palladium activated carbon and distilling off the solvent, 86 g of 5-(4-butylphenyl)-2-(4-hydroxyphenyl)pyrimidine was obtained by recrystallizing the residue from a mixed solvent of n-hebutane-toluene. Obtained. Melting point is 17
The temperature was 2.5-173.3°C.

Next, a mixture of 10 g of 60% sodium hydride, 59 g of 5-(4-butylphenyl)-2-(4-hydroxyphenyl)pyrimidine, 400 ml of tetrahydrofuran, and 800 g of dimethylformamide was added to
71 g of 5-2-tetrahydropyranyloxy-1-(p-)luenesulfonyloxy)-propane produced by the method described in No. 800 was added, and the mixture was stirred at 60°C for 4 hours.

Toluene was added, washed with alkali, then water, the solvent was distilled off, 80 ml of ethanol 800-1 hydrochloric acid was added to the residue, stirred at 60°C for 1 hour, allowed to cool to room temperature, and collected the precipitated crystals. By recrystallization from ethyl acetate, 48 g of S-5-(4-butylphenyl")-2-(
4-(2-hydroxypropyloxy)phenyl]pyrimidine was obtained. This material exhibited liquid crystallinity, and its phase transition point was as follows.

5-5- (4-butylphenyl)-2-(4-(2-
Hydroxypropyloxy)phenylpyrimidine 5g
, dicyclohexylcarbodiimide 4.7g, dimethylaminopyridine 0.35g, n-pentanoic acid 2g
, dichloromethane 150- was stirred for 2 hours.

The precipitated crystals were separated by filtration, the filtrate was washed with alkali and then water, the solvent was distilled off, and the residue was recrystallized from ethanol.
g of 5-5-(4-butylphenyl)-2-[4-(
2-Pentanoyloxypropyloxy)phenyl]pyrimidine was obtained. Elemental analysis, NMR-spectrum, IR
-It was confirmed by the spectrum that it was the desired product. Moreover, this material exhibited liquid crystallinity, and its phase transition point was as follows.

Example 2 S-5-(4-butylphenyl)-2-(4-(2-
(S-2-Butyloxypropionyloxy)propyloxyphphenyl)pyrimidine (R1 in the formula (■)
is the production of Ca Hq-15-5-(4-butylphenyl)-2-(4-(2-
Hydroxypropyloxy)phenylpyrimidine 5g
, N,N'-dicyclohexylcarbodiimide 4.7
g, 4-N, N-dimethylaminopyridine 0.35
A mixture of 3 g of S-2-butyloxypropanoic acid and 150 g of dichloromethane was stirred for 2 hours. The precipitated crystals were separated by filtration, the filtrate was washed with alkali and then water, the solvent was distilled off, and the residue was recrystallized from ethanol to give 3 g of S-5-(4-butylphenyl)-2-( 4-
(2-(S-2-butyloxypropionyloxy)propyloxyphphenyl)pyrimidine was obtained. It was found to be the desired product by elemental analysis, NMR-spectrum, and (1) R-spectrum. This material also exhibited liquid crystallinity and its phase transition point was as follows.

Example 3 R-5°-(4-butylphenyl)-2-(4-(2
-hexyloxypropyloxy)phenyl]pyrimidine (in formula (I), R1 is Ca H9-1R2 is -Ca
HI3) 5 g of R-5-(4-butylphenyl)-2-(4'-(2-hydroxypropyloxy)phenyl)pyrimidine produced in the same manner as in Example 1, 066 g of 60% sodium hydride, 2.4 g of hexyl bromide was added to a mixture of 30+d of tetrahydrofuran and stirred at 60°C for 4 hours.Toluene was added, washed with alkali and then with water, the solvent was distilled off, and the residue was recrystallized from ethanol. and 4.8 g of R-5-(4-butylphenyl)-2-(
4-(2-hexyloxypropyloxy)phenyl]
Pyrimidine was obtained. Elemental analysis, NMR-spectrum, I
The R-spectrum revealed that it was the desired product.

This material also exhibited liquid crystallinity and its phase transition point was as follows.

Example 4 (Usage example 1) First, a composition using the following liquid crystal compound was prepared.

The phase transition point of the above composition was as follows.

Furthermore, this material did not exhibit ferroelectricity and had a spontaneous polarization value of zero.

The compound obtained in Example 2: S-5-(4-butylphenyl)-2-(4-(2-
A chiral smectic liquid crystal composition was prepared by adding 20% by weight of (S-2-butyloxypropionyloxy)propyloxy)phenyl)pyrimidine. The phase transition point of the substance was as follows.

Further, the magnitude of spontaneous polarization and the tilt angle of this liquid crystal composition were each 11.5 nC/cIA at 15°C.

It was 6.0°.

This composition was applied with polyvinyl alcohol as an alignment treatment agent, and the surface was rubbed and injected into a cell with a cell thickness of 2-2 and equipped with transparent electrodes subjected to parallel alignment treatment. When a voltage of 5V was applied to the analyzer, a change in the transmitted light intensity was observed.

The response speed is calculated from the change in transmitted light intensity at this time, and is 15
The time was 40 μsec at ℃.

As described above, the compound of the present invention can be said to be an extremely useful ferroelectric liquid crystal material in realizing high-speed response.

Example 5 (Use Example 2) The compound of the present invention obtained in Example 1 was added to a nematic liquid crystal composition (using ZLI 1132 manufactured by Merck & Co.): 5-5-
(4-Butylphenyl)-2-C4-(2-pentanoyloxypropyloxy)phenyl]pyrimidine
% by weight was added to prepare a chiral nematic liquid crystal composition. When this chiral nematic liquid crystal composition was injected into a wedge-shaped cell subjected to parallel alignment treatment and observed under a polarizing microscope, the helical pitch was observed as follows.

As described above, the temperature dependence of pitch is extremely flat, and the compound of the present invention was found to be an excellent pinch adjuster for chiral nematic liquid crystal compositions.

Example 6 (Use Example 3) A TN type display cell was obtained by injecting a nematic liquid crystal composition consisting of the following into a cell with an electrode spacing of 10μ, and when this was observed with a polarizing microscope, it was found that a reverse twist domain had occurred. observed. The cell used was coated with polyvinyl alcohol as an alignment treatment agent, and its surface was rubbed to perform parallel alignment treatment.

The compound of the present invention obtained in Example 1 was added to the above nematic liquid crystal composition: S-5-(4-butylphenyl)-
2-(4-(2-pentanoyloxypropyloxy)
0.1% by weight of phenyl]pyrimidine was added, and the same T
When observed in an N-type cell, the reverse twist domain was eliminated and a uniform nematic phase was observed.

(Effects of the Invention) According to the compounds of the present invention, any of them can be used as a component of a ferroelectric liquid crystal composition, and has the effect of significantly increasing the spontaneous polarization value. It can be applied to materials that enable responsive displays.

Furthermore, when the compound of the present invention is used as a component of a liquid crystal composition,
It is an extremely useful ferroelectric liquid crystal material that can derive a suitable ferroelectric liquid crystal temperature range. Furthermore, a chiral nematic liquid crystal composition obtained by adding the compound of the present invention to a nematic liquid crystal composition is useful as a pitch control agent.

Claims (5)

[Claims] (1) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, in the above formula, R^1 represents an alkyl group or alkoxy group having 1 to 20 carbon atoms, and R^2 represents an alkyl group having 1 to 20 carbon atoms. An optically active compound represented by an alkyl group, an acyl group, or an alkoxyacyl group containing the following, and * indicates that the carbon atom is an asymmetric carbon. (2) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, in the above formula, R^1 represents an alkyl group or alkoxy group having 1 to 20 carbon atoms, and R^2 represents an alkyl group or alkoxy group having 1 to 20 carbon atoms. 1. A liquid crystal composition comprising at least one compound represented by an alkyl group, an acyl group, or an alkoxyacyl group, and * indicates that the carbon atom is an asymmetric carbon. (3) The liquid crystal composition according to claim 2, wherein the liquid crystal phase exhibited is a chiral smectic phase. (4) The liquid crystal composition according to claim 2, wherein the liquid crystal phase exhibited is a chiral nematic phase. (5) General formula ▲ Numerical formulas, chemical formulas, tables, etc. using a chiral liquid crystal composition characterized by containing at least one compound represented by an alkyl group, an acyl group, or an alkoxyacyl group, and * indicates that the carbon atom is an asymmetric carbon. An electro-optical element configured with