JPS60149564A - 2-(beta-substituted ethyl)-5-substituted pyridine - Google Patents

Abstract

NEW MATERIAL:A compound expressed by formula I (R and R' are 1-15C alkyl and alkoxyl; X is phenylene, biphenylene or expressed by formulas V-VIII). EXAMPLE:2-[beta-(4-Propyloxyphenyl)ethyl]-5-pentyloxypyridine. USE:A component which is a liquid crystal substance for liquid crystal compositions, having improved compatibility with another liquid crystal compound, and capable of reducing the driving voltage of liquid crystal display elements by the compositions prepared from a mixture thereof. PREPARATION:A 3-substituted-6-methylpyridine expressed by formula II is reacted with a 4-substituted benzaldehyde or trans-4-substituted cyclohexylaldehyde expressed by formula III in a solution of LiN (i-propyl)2 in tetrahydrofuran to form a compound expressed by formula IV, which is then dehydrated with KHSO4 and catalytically reduced with H2 in the presence of Pd/C catalyst to afford the aimed compound expressed by formula I .

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel liquid crystal material and a liquid crystal composition containing the same.

There are various display methods of liquid crystal display elements that utilize the optical anisotropy and dielectric anisotropy of liquid crystal materials, such as TN type, D8 type, guest-host type, dual frequency method type, DAP type, and white tiller type. There are several methods, and each method requires different properties of the liquid crystal material used. For example, depending on the type of display element, a liquid crystal material with positive or negative dielectric anisotropy may be required, or a material with an intermediate value may be suitable. The liquid crystal material used must exhibit a liquid crystal phase over as wide a temperature range as possible and be stable against moisture, heat, air, light, etc. At present, there is no single compound that satisfies all of these conditions, and several types of liquid crystal compounds and non-liquid crystal compounds are mixed and put into practical use.

Recently, there has been an increasing demand for liquid crystal display elements that operate over a wide temperature range, that is, from low temperatures to high temperatures. Furthermore, there is a need for a liquid crystal composition that can lower the threshold voltage and saturation voltage required to drive a display element.

An object of the present invention is to provide a compound useful as a component of a liquid crystal composition that satisfies such requirements.

That is, in the present invention, in the general formula ((I), R or R' represents alkyl having 1 to 15 carbon atoms or X)()-. ) 2-(β-substituted ethyl)-5-substituted pyridine and a liquid crystal composition containing the same.

The compound of the present invention in which X in formula (1) is two rings has a liquid crystal phase. The compound of the present invention has excellent compatibility with other liquid crystal compounds, and can lower the driving voltage of a liquid crystal display element using a composition mixed with other liquid crystal compounds.

Next, a method for producing the compound of the present invention will be described.

Adding 3-substituted-6-methylpyridine (1) to a solution of lithium diisopropylamide in tetrahydrofuran,
4-substituted benzaldehyde c) or trans-4
-React with substituted chlorohexyl aldehyde (1) ・2
-(β-(4-substituted phenyl)-β-hydroxyethyl)-5-substituted pyridine (ff) or 2-(β-(trans-4-substituted cyclohexyl)-β-hydroxyethyl)-δ-substituted pyridine ( IV). This compound was then dehydrated with potassium hydrogen sulfate and then treated with palladium-
By catalytic reduction using carbon, the desired 2-
(β-(4-substituted phenyl)ethyl)-5-substituted pyridine (1) or 2-(β-(trans-4-1-substituted ν-chlorohexyl)ethyl)-δ-substituted pyridine (1) is obtained.

This is shown in the chemical formula as follows.

(Seal) (I) (V) The present invention will be explained in more detail below using Examples.

Example 1 2-(β-(4-7′lohoxyphenyl)ether)-5
-Pentyloxypyridine 3-bentyloxy-6-methylpyridine4. (f (
0.02 mol) to lithium diisopropylamide (0.02 mol)
03 mol) in tetrahydrofuran solution 40-, -7
The mixture was added while maintaining the temperature at 0° C., and then 3.7 t (0.02 mol) of 4-broboxypenzaldehye F was added dropwise, and stirring was continued at this temperature for the next 1 hour. After further stirring at room temperature for 2 hours, 50 tat of water was added! and extracted with 100 d of toluene. This toluene layer was separated, washed with 2N hydrochloric acid, then washed with an aqueous sodium carbonate solution, and then washed with water until the washing water became neutral. Next, the toluene layer was distilled off under reduced pressure, and the remaining solid was recrystallized from methanol to give 2-(
β-(4-proboxyphenyl)-β-hydroxyether)-5-pentyloxypyridine 1. Melting point: 128°C). Next, add 0.0% potassium hydrogen sulfate to this compound.
3F was added and stirred at 180°C for 2 hours.

After the reaction is completed, 50% of water, 507% of chloroform! After extraction with chloroform, the extract was washed with water until the washing water became neutral. This chloroform layer was distilled off under reduced pressure and
-(β-(4-Propoquinpuenyl)vinyl)-5-pentylox Vpyridine 0.62 was obtained. Dissolve this compound in toluene 50- and palladium-carbon 0,2
f was added and catalytic reduction was carried out at room temperature and pressure. After the reaction was completed, the catalyst was removed, the solvent was distilled off under reduced pressure, and then recrystallized with ethanol to obtain the target product, 2-(β,-(4-7'-methyloxyphenyl)ethyl)-5-pentyl. Oxypyridine was obtained. The yield was 0.4°C and the melting point was 48.0°C.

Example 2.3 Instead of 4-propoquine benzaldehyde, 4-(4
'-pentylphenyl)benzaldehydoma or 4-(
) Lance-4'-propylcyclohexyl)benzaldehyde was used in the same manner as in Example 1,
2-(β-(4“-pentylbiphenyl-4′) ether)-5-pentyloxypyridine or 2-(p-(
) trans-4'-propylcyclohexyl) phenethyl)-5-pentyloxypyridine were synthesized.

These physical properties are shown in Table 1 together with the results of Example 1.

In the table, C, 81N, and E represent crystal, smectic phase, nematic phase, and isotropic liquid phase, respectively, and the number mark indicates that the phase in the column above it exists, and the - mark indicates that the phase in the column above it exists. The number indicates the phase transition temperature (C) between the sandwiched phases.

Example 4 (Application example) Trans-4-propyl-(4'-cyanophenyl)cyclohexane 24% Trans-4-pentyl-(4'-cyanophenyl)cyclohexane 36% Trans-4-hebutyl-(4'- The nematic clearing point of a liquid crystal mixture having the following composition: cyanophenyl)cyclohexane 25% 4-cyano-4'-()lans-4-pentylcyclohexyl)piphenyl 15%
℃, viscosity is 28C9s dielectric anisotropy value (hereinafter Δ6
) is +11.6 and the optical anisotropy value (hereinafter abbreviated as Δn) is 0.140. The threshold voltage of the liquid crystal cell, which is sealed in a TN cell with a cell thickness of 10 μm, is 1.75 V.
, the saturation voltage was 2.40V. This mixture 90M@
and 2-(β-(4-propyloxyphenyl)ethyl)-5-pentyloxypyridi 71 of Example 1 of the present invention
The nematic clearing point of the liquid crystal composition consisting of 0 parts by weight is 59.6°C, the viscosity is 29cpsΔ6 at 20°C, and +10.
2, Δn is 0,131, L, threshold voltage is 1.54
The saturation voltage was 2.16V.

As described above, by applying the present invention, it was possible to lower the threshold voltage and saturation voltage of a liquid crystal display element.

Patent applicant Chisso Corporation Proceeding Amendment 1985/1985 Commissioner Manabu Shiga Z Name of the invention 2-(β-Substituted ethyl)-5-substituted biry) Syn & Amendment Relationship with the case of the person who did the patent application: 3-6-32 Nakanoshima, Kita-ku, Osaka-shi, Osaka Prefecture (530)
(zo'7) Chisso Co., Ltd. Representative Sadayuta Nogi Agent 2-8-1 Shinjuku, Shinjuku-ku, Tokyo (160) α Column I of "Detailed Description of the Invention" of the Specification Subject to the Amendment Contents of the Amendment (1) Page 7, line 9 to last line of the specification, “Example 2.3.
...shown in Table 1. ” [Examples 2 to 7 The following compounds were synthesized by a method similar to Example 1.

2-(β-Ce-pentylbiphenyl-4')ethyl)-5-pentyloxypyridine 2-(p-()9-41-globylcyclohexyl)phenethyl 1-5-
Pentyloxypyridine 2-(β-(41-pentylbiphenyl-47)ethyl)-5-ethylpyridine 2-(p-()lans-4'-pentylcyclohexyl)phenethyl)-5-ethylpyridine 2-(β −←e−
Ethyl biphenylyl (41) ethyl)-5-propylpyridine 2-(β-(4'-propyl and phenylyl-4')ethyl)-5-propylpyridine The physical properties of these compounds are shown in Table 1 along with the results of Example 1. Shown below. ” he corrected.

(2) Table 1 on page 8 of the circular is revised in the attached circular.

(3) "Example 4" on page 9, line 7 of the same book was changed to "Example 8"
I am corrected.

a Attached documents Attachment (Table 1) that's all

Claims (2)

[Claims] (1) General formula (wherein R or R' represents an alkyl group or an alkoxy group having 1 to 5 carbon atoms, and X is omitted 2-(β-
Substituted ethyl)-5-substituted pyridine. (2) General formula (in the formula, 几 or R' represents an alkyl group or an alkoxy group having 1 to 15 carbon atoms.
Shows koX. ) 2-(β-substituted ethyl)-
A liquid crystal composition containing a 5-substituted pyridine.