JPS61268652A - Acetylenylphenyl ester derivative - Google Patents

Abstract

NEW MATERIAL:The compound of formula I (R is 1-9C straight-chain alkyl; R' is 1-9C straight-chain alkyl, alkoxy, halogen or cyano; the ring A is benzene or cyclohexane ring, and the cyclohexane ring has trans-configuration). USE:A nematic liquid crystal compound having weak negative dielectric anisotropy. Useful as a material for a dynamic light-scattering display call as a mixture of other nematic liquid crystal compound having negative or weak positive dielectric anisotropy, and for a field-effect display cell as a mixture with other nematic liquid crystal compound having strong positive dielectrid anisotropy. PREPARATION:The compound of formula I can be produced by reacting the compound of formula II with the compound of formula III in an inert organic solvent such as ether, benzene, toluene, etc., in the presence of a base (e.g. pyridine).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel nematic liquid crystal compound of an acetylenyl phenyl ester derivative useful as an electro-optical display material.

[Conventional technology]

M-Shut (M, 5) is a typical liquid crystal display cell.
chadt) etc. [APPLIED P)ffsIcs
LETTER 8181275128 (1971)) or CPROCEED such as the field effect mode cell proposed by G-Hailmsier.
ING OF THE 1. E, E, E.

561162-1171 (1968)) or the dynamic light scattering cell (dynamic scattering mode φ cell) proposed by G.H. Beilmeyer (
G-HHellmeisr) etc.C-APPLIEDP
HYSIC8LETTER813, 91 (1968)
] Or DL White (DL Whit@
), etc. [: JOURNAL OF APPLIED PH
There is a dust host type cell proposed by Y10 IC845, 4718 (1974).

The liquid crystal materials used in these liquid crystal display cells are required to have various properties, but having a nematic phase over a wide temperature range including room temperature is an important property that is commonly required for all types of display cells. .

Most of the materials that can be used for practical purposes with such properties are usually produced by mixing several or more components, consisting of a compound that has a nematic phase near room temperature and a compound that has a nematic phase at a temperature above room temperature. It is arranged by. Many of the above-mentioned mixed liquid crystals currently in practical use are required to have a nematic phase over the entire temperature range of at least -30°C to +65°C. In order to meet such requirements, 4,4'-substituted terphenyl is used as a compound having a nematic phase in a temperature range higher than room temperature.

4.4'-[Converted piphenylcyclohexane, 4,4 di-substituted hensoylbenzoic phenyl esters, etc., which have a crystalline-nematic phase transition temperature of about 100°C (C-
Compounds having a nematic phase-isotropic liquid phase transition temperature (N-I point) of about 200° C. are often used.

In recent years, as liquid crystal display cells have been used for a variety of purposes both indoors and outdoors, there has been a need for cells with a nematic temperature range higher than +65°C. For this purpose, a compound is required which has a higher nematic phase-isotropic liquid phase transition temperature (N-I point) than conventional compounds.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a compound with a high N-I point.

[Means for solving problems]

The present invention has solved the above problems by providing a compound represented by the general formula.

The compound of formula (1) according to the present invention can be produced according to the following production method.

R 唖X can coct (II) R＜口Σ＜E
)−Coo(QΣC=CCΣR' (I) Formula (I
O) Compound Formula (r) according to the present invention is obtained by reacting a compound of formula [phase] in an inert organic solvent such as ether, benzene, or toluene using a basic compound such as male lysine as a catalyst.
Manufacture the compound.

Table 1 lists the transition temperatures of representative compounds of formula (I) thus prepared.

In the table, C represents a crystalline phase, S represents a solid phase, N represents a nematic phase, and C represents an isotropic liquid phase.

The compound of formula (I) according to the invention is a nematic liquid crystal compound with weak negative dielectric anisotropy, and therefore, for example:
It can be used as a material for dynamic light scattering display cells in a mixture with other nematic liquid crystal compounds that have negative or weak positive dielectric anisotropy, and also has strong positive dielectric anisotropy. It can be used as a material for field effect display cells in the form of a mixture with other nematic liquid crystal compounds.

Thus, preferred representative examples which can be used in admixture with compounds of formula (I) include, for example, 4,4'-substituted benzoic acid phenyl ester, 4,4'-11-substituted cyclohexane, phenyl carginate, Ester, 4,4'-substituted cyclohexanecal? acid piphenyl ester, 4 (4
-Substituted cyclohexanecalyloxy)benzoic acid 4'
-Substituted phenyl ester, 4(4-substituted cyclohexyl)benzoic acid 4'-substituted phenyl ester, 4C4-R-substituted cyclohexyl)benzoic acid 4'-substituted cyclohexyl ester, 4.4'-substituted biphenyl, 4.4'-[ 11
t-phenylcyclohexane, 4,4'-substituted terphenyl, 4,4'-biphenylcyclohexane, 2(4'-
Examples include 5-substituted pyrimidine (11-substituted phenyl) and the like.

Table 2 shows 90% by weight of the base liquid crystal (4), which is currently widely used as a nematic liquid crystal material with excellent time-division driving characteristics, and 10% by weight of compound 1 of formula (I) shown in Table 1. The N-I points measured for each mixed liquid crystal consisting of the following are shown, and for comparison, the N-I points measured for the base liquid crystal (4) itself are shown. In addition, the mother liquid crystal material is 200% by weight, 16% by weight, 8% by weight, 8% by weight, 8% by weight, 8% by weight, 8% by weight, and 8% by weight in Table 2 N-I. Point (6) (2) 54.0 (g) + M1 80.6 From the data posted in Table 2, the compound of formula (1) is.

By adding 10% by weight to the mixed liquid crystal, the N-I point of
It can be understood that the temperature can be increased by 0°C or more.

Thus, the compound of formula (I) has high practical value in that the upper limit of the operating temperature range can be raised by adding evening light.

The effects of the present invention are also clearly demonstrated by the following comparative experiments. Known compounds of formulas used for the purpose of increasing the N-I point of mixed liquid crystals were mixed in various proportions of the above-mentioned parent liquid crystals (A) and K. Similarly, one of the compounds according to the present invention, ie, the compound of formula (2), was mixed in various proportions with the parent liquid crystal (2).

Regarding the two types of mixed liquid crystals obtained in this way, each N
- Point I was measured. Based on these measurement results, the relationship between the N-I point and the amount added is shown in FIG. 1 of the attached drawings.

Based on these facts, the compound of formula (1) according to the present invention has a higher N-I ratio than typical known similar compounds.
It can be seen that the increase in points is much larger.

〔Example〕

Example 1 Compound of formula H÷CmiCbe)Qn-C,sH2 23.6.
9 (0,100 mol), formula n -CsH7+C0
Ct compound (0,100 mol) in toluene 2
0011: After dissolving, 15.8 JI (0,200 mol) of pyridine was added dropwise to the solution while stirring at room temperature.

After the addition was completed, the mixture was heated under reflux for t-2 hours.

After the reaction was completed, the reaction product was extracted with toluene.

After washing the extract with water and drying, toluene was distilled off from this solution under reduced pressure, and the resulting nine reaction products were purified by recrystallization with ethanol to obtain the following compound 32.81 (0,070 mol).

Yield 70% Transition temperature 188°C (C-+S)
199°C (S-N) 300°C or higher (N) [Effect of the invention] The compound of formula (1) according to the present invention is a liquid crystal compound with a high N-I transition temperature, and is added in small amounts to known liquid crystal mixtures. By mixing, the nematic phase-isotropic liquid phase transition temperature (N
-1 point) can be significantly increased. Furthermore, the formula (
The compound I) is a 4,4-substituted cyclohexylcal? compound reported by the present applicant in Japanese Patent Application Laid-Open No. 83694/1983 as a nematic liquid crystal material with excellent time-division driving characteristics.
Since it has extremely good compatibility with phosphoric acid phenyl ester, even better mixed liquid crystals can be obtained by mixing it with these compounds.

[Brief explanation of drawings]

FIG. 1 shows one of the compounds according to the present invention (IILl
) and known compounds with similar structures (1)
2 is a chart showing the relationship between the NI point of a mixed liquid crystal obtained by adding each of ) to the currently widely used base liquid crystal (4) and the amount of addition of (, ) or (Ken 1).

Claims (1)

[Claims] General formula ▲ Numerical formulas, chemical formulas, tables, etc. ▼ In the formula, R represents a straight chain alkyl group having 1 to 9 carbon atoms, and R' represents a straight chain alkyl group having 1 to 9 carbon atoms. represents an alkyl group, an alkoxy group, a halogen atom, or a cyano group. ▲There are mathematical formulas, chemical formulas, tables, etc. ▼ represents a benzene or cyclohexane ring, and the cyclohexane ring has a trans (equatorial-equatorial) configuration. A compound represented by