JPS6147469A - 5-cyano-2-substituted pyrimidine - Google Patents

Abstract

NEW MATERIAL:The 5-cyano-2-substituted pyrimidine of formula I (R is 1-10C alkyl; at least one of the ring A and ring B is group of formula II and the other is group of formula II or formula III). EXAMPLE:5-Cyano-2-[4-(trans-4'-butylcyclohexyl)phenyl]pyrimidine. USE:Useful as a constituent component of a liquid crystal material. The liquid crystal composition for TN display element containing said compound has broad liquid crystal temperature range extended to the high-temperature side, large refractive index anisotropy, and not small dielectric anisotropy. It can be used over a wide temperature range and is effective to improve various response characteristics, sharpness, and contrast. PREPARATION:The compound of formula I can be prepared by reacting the nitrile derivative of formula IV with hydrogen chloride gas in a solvent, reacting the reaction product with ammonia gas, and reacting the product with the acrolein derivative of formula V in the presence of a basic catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel organic compounds, and more particularly to novel liquid crystal compounds useful as components of liquid crystal materials.

As is well known, liquid crystal compounds are used in various display devices by utilizing properties such as dielectric anisotropy and refractive index anisotropy in the liquid crystal phase. This is a liquid crystal display element that applies the thermo-optical effect of liquid crystals and other optical effects.As electronics progresses, electric field effects such as the twisted nematic effect and the guest-host effect are applied. Many liquid crystal compounds are used in liquid crystal display elements.

These liquid crystal materials cannot be used as a single compound in terms of their characteristics, such as liquid crystal temperature range, operating voltage, response performance, etc., and for practical purposes, it is necessary to combine several types of liquid crystal compounds or non-liquid crystal compounds. By mixing, we obtain a material that can withstand use, depending on the situation.

An object of the present invention is to provide a compound useful as a liquid crystal component constituting a physically and chemically stable liquid crystal composition with excellent practical performance.

The BA of the present invention is a 5-schifno-2-substituted pyrimidine represented by the general formula (wherein R represents a furkyl group having 1 to 10 carbon atoms), and a liquid crystal composition containing the compound.

Compound (I) of the present invention has positive dielectric constant anisotropy,
It is a liquid crystal compound that has an extremely large refractive index anisotropy, has a fairly wide liquid crystal temperature range at high temperatures, and has excellent stability against heat, light, air, electricity, etc. required for liquid crystal display elements.

Since the compound of the present invention has good compatibility with other liquid crystal compounds, one or several types of liquid crystals such as biphenyl, ester, cyclohexanecarboxylic acid phenyl ester, phenylcyclohexane, phenylmetadioxane, and pyrimidine compounds can be used. It can be mixed with a liquid crystal composition consisting of a compound of the following system. The liquid crystal composition for a TN display element containing the compound of the present invention has excellent characteristics such as a wide liquid crystal temperature range on the high temperature side, a large refractive index anisotropy, and a not small dielectric anisotropy value. Therefore, it can be used in a wide temperature range and exhibits effects such as improving response characteristics, sharpness, and contrast.

The compound of the present invention can be synthesized according to the following reaction formula.

(In the formula, R represents a furkyl group having 1 to 10 carbon atoms, and first,
The nitrile derivative (It) is reacted with hydrogen chloride gas in an alcohol solvent to obtain an imidoether hydrochloride derivative (S).Next, the compound (III) is reacted with hydrogen chloride gas in an alcohol solvent.
By reacting with ammonia gas, amidine hydrochloride derivative (I
V) is obtained. Next, compound (IVI) and an acrolein derivative are subjected to a condensation cyclization reaction in the presence of a suitable salt/base catalyst (eg, pyridine and triethylamine) to obtain the desired compound (1).

The compounds of the present invention will be explained in detail with reference to Examples below.

Example 1 Preparation of 5-Sifnor 2-(4-() lance-4'-butylcyclohexyl)phenyl]pyrimidine 4-() lance-4'-butylcyclohexyl)benz7midine hydrochloride5. Of (0,02mat) and α-
Schifnow β-dimethyl 7mino 7chlorein 2.2 t
(0,02moj) and Tori Z f /L, Afy25
d and pyridine 25- were heated under reflux for 5 hours while stirring. After cooling the reaction solution, toluene Loom and water 1001
After adding Lt, the product was extracted into a toluene layer, and the extract was washed with water three times, and then the toluene solution was dried over anhydrous sodium sulfate. Thereafter, the toluene solution was concentrated under reduced pressure using an evaporator, and the remaining solid was recrystallized from toluene to obtain the target compound 5-cyano-2-(4-()lans-4'-butylcyclohexyl)phenyl]pyrimidine. 3.1? (
0.01 mol) was obtained.

The elemental analysis values of this compound were in good agreement with the theoretical values as shown below.

Moreover, the phase transition point of this compound was as follows.

Crystal phase - smectic phase transition point 149°C Smectic phase - nematic phase transition point 196°C Nematic phase - isotropic liquid phase transition point (hereinafter abbreviated as N-I point) 216°C Example 2 C, smectic phase is abbreviated as 81, nematic phase is N1, and isotropic liquid phase is abbreviated as I.

Example 7 (Usage Example) The N-I point of the liquid crystal composition (A) consisting of: 52.1
℃, viscosity ηゎ at 20℃ is 23.4 cP% dielectric anisotropy Δε is l 1,2 (t, = 15.9, g, = 4.
7), when this was sealed in a TN cell with a cell thickness of 10 μm, the threshold voltage was 1.54 V, the saturation voltage Fi2°13 V, and the refractive index anisotropy Δn was 0°119 (ne = 1.
609, nQ”1.490).

A liquid crystal composition prepared by adding 5 parts by weight of the compound 5-cyano-2-(4-()lans-4'-butylcyclohexyl)phenyl]pyrimidine shown in Example 1 of the present invention to 95 parts by weight of the compound (A). The N-4 point of rises to 60.9℃, and η2o
is 26.3 cP, and Δε is 12.1 (ε, =
17.2, ε5-5,1), and the same TN
The voltage at the threshold J of the one sealed in the cell is 1.60 V, the saturation voltage is 2°28 V, and Δn jd 0.130 (no = 1.621.
no=1.491).

that's all

Claims (2)

[Claims] (1) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R represents an alkyl group having 1 to 10 carbon atoms, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ Numerical formulas, chemical formulas,
There are tables, etc. At least one of ▼ indicates ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and the other indicates ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. 5-cyano-2-substituted pyrimidines represented by (2) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R represents an alkyl group having 1 to 10 carbon atoms, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ Numerical formulas, chemical formulas,
There are tables, etc. At least one of ▼ indicates ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and the other indicates ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. ) A liquid crystal composition containing at least one 5-cyano-2-substituted pyrimidine represented by the following formula.