JPH013131A - Bicyclohexyl biphenyl derivatives - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to bicyclohexyl biphenyl derivatives useful as electro-optic display materials.

[Conventional technology]

Typical liquid crystal display cells are M-Shirt) and (M-
8chadt) etc. (APPLIED PHYSIC8
LETTER8.

127-128 (1971)] or the field effect mode cell proposed by G.H.
meier) etc. (PROCEEDING OF TH
E1. E, E, E.

56 1162-1171 (1968)] or the dynamic scattering mode cell proposed by G-H-Hellmeier et al.
D PHYSIC3LETTER813, 91 (196
8) ) or D. L. White (I) L-W
hite ) etc. (JOURNAL 0FAPPLIED
P) ffsIcs 45.4718 (1974)]
Examples include the dust-hosted cell proposed by

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. Prepared by. Most 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, compounds having a nematic phase in a temperature range higher than room temperature include 4-substituted 4'-substituted terphenyl, 4-substituted biphenyl, 4'-substituted cyclohexane, and 4-substituted 4'-substituted terphenyl.
- such as substituted benzoyloxybenzoic acid 4'-substituted phenyl esters, which have a crystalline phase-nematic phase transition temperature (C-N point) of about 100°C and a nematic phase-isotropic liquid phase transition temperature (C-N point) of about 200°C. Compounds having a N-I point) are often used. Recently, there has been a demand for liquid crystal materials that have a nematic phase in a higher temperature range. In order to meet this demand, 4-substituted bicyclohexyl 4'
A compound having a high N-I point of about 300°C, such as -substituted biphenyl, is disclosed in JP-A-59-20235.

It was proposed and used in Japanese Patent Nos. 59-27839 and 60-92228.

[Problem that the invention seeks to solve]

However, these compounds usually have a smectic phase and have a drawback that the smectic phase-nematic phase transition temperature (S-N point), which is the lower limit of the temperature range in which they exhibit a nematic phase, is high.

In order to increase the N-I point of the mixed liquid crystal, these S-N
When a compound with a high point is added to a nematic mixed liquid crystal that is currently in practical use as a host liquid crystal, it has the undesirable property that a smectic phase appears in a low temperature region.

The problem that the present invention seeks to solve is to provide a new nematic liquid crystal compound having a high N-1 point and a low S-N point.

Means for Solving Problem C] In order to solve the above problems, the present invention provides - a boat lamp [wherein R represents a linear alkyl group having 1 to 1 o carbon atoms, and X represents a methyl represents a group or a fluorine atom, and Y is a fluorine atom or a direct lance (equatorial-equatorial) configuration having 1 to 7 carbon atoms. ] is provided.

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

(R, X and Y in the above formulas (IO, (2) and each formula of the plane have the same meanings as R, X and Y in formula (1), respectively.) First step - Compound of formula (If) The Grignard reagent of formula (2) is prepared by reacting with metallic magnesium powder in an ether solvent such as anhydrous ether or anhydrous tetrahydrofuran.

Second step - The compound of formula (2) and the iodobenzene derivative (2) are reacted in an ether solvent such as anhydrous ether or anhydrous tetrahydrofuran using i4 radium chloride as a catalyst. After adding dilute hydrochloric acid to the reaction product to make it acidic, 1
The reaction product is extracted with toluene. After washing the extract with water and drying, the solvent is distilled off under reduced pressure. Next, the desired compound of formula (1) can be isolated by recrystallizing the reaction product from an alcoholic solvent such as ethanol.

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

1st Omoteya RX Y Transition temperature (G) 1
n-CI(-CH3-F-96(C-)SB)137
(SB□N) 233(N:I) 2 n-CH-CH-CH3-103(C-+N)
9 i (N; 28B) 246 (N:: I) (In the table, C represents a crystalline phase, SR represents a smectic B phase, N represents a nematic phase, and H represents an isotropic liquid phase.) According to the present invention The compound of formula (I) is a nematic liquid crystal compound with a weak positive dielectric anisotropy and can therefore be used, for example, in a mixture with other nematic liquid crystal compounds with a negative or weakly positive dielectric anisotropy. It can be used as a material for dynamic light scattering type display cells, and it can also be used as a material for field effect type display cells in a mixture with other nematic liquid crystal compounds with strong positive dielectric constant anisotropy. can.

Preferred representative examples that can be used in combination with the compound of formula (1) include 2, for example, 4-substituted benzoic acid 4'-substituted phenyl ester, 4-substituted cyclohexane carboxylic acid 4'-N substituted phenyl ester, 4-f substituted cyclohexanecarboxylic acid 4'-8m biphenyl ester, 4-(4-substituted cyclohexanecarbonyloxy)
Benzoic acid 4'-fm phenyl ester, 4-(4-f substituted cyclohexyl) Benzoic acid 4'-substituted phenyl ester, 4-(4-substituted cyclohexyl)benzoic acid 4'-
Substituted cyclohexyl ester, 4-ft substituted 4'-ft
substituted hyphenyl, 4-f substituted phenyl-4'-substituted cyclohexane, 4-substituted 4'-substituted terphenyl, 4-substituted biphenyl 4'-[substituted cyclohexane, 2-(4-i substituted phenyl)-5-substituted Examples include pyrimidine.

Table 2 shows the SN points and NI points of known compounds similar to the compound of formula (1) according to the present invention.

Table 2 (JP-A-6O-92228) As is clear from the comparison between Tables 1 and 2, the compounds according to the present invention have 200%
℃ or higher, and is a known similar compound)
It also has a significantly lower S-N point.

Example 1゜Anhydrous tetrahydrofuran 1. Add 0.35 g of metallic magnesium powder and 0.15 g atom of NO) to (l).

2-bromo-5-fluorotoluene in a nitrogen stream 2.9
．． 9 (0,015 mol) was slowly added dropwise, and 1
A Grignard reagent was prepared by reacting for a period of time.

Next, 4-C) Lance-4'-() Lance-4"-n-
Butylcyclohexyl)cyclohegycyl]iodobenzene 4.3g (0,010 mol) e[Water Tetrahydrofuran 20ml 1K Dissolved, To this solution to which a catalytic amount of palladium chloride was added, the above Grignard reagent was added dropwise at room temperature, and then for 5 hours Heat reflux to 51f. After the reaction is complete, 9
After making it acidic by adding % hydrochloric acid.

The reaction product was extracted with toluene, the extract was washed with water, dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure. The reaction product was recrystallized twice from ethanol to obtain compound 2 below.
．． 3.9 (0,0057 mol) was obtained.

Revenue rate 57% Transition temperature 96℃ (c-+5B) 137℃ (S B’: 2N) 233℃ (N=I) Example 2 In the same manner as in Example 1, the following compound was obtained.

Yield: 49% Transition temperature: 103°C (C-)N) 91°C (Nヰ5B) 246°C (N-r) [Effects of the invention] The compound according to the present invention has a high N-I point and a low S-N point. has. Therefore, by mixing the compound according to the present invention with a nematic mixed liquid crystal that is currently in practical use as a base liquid crystal, the N-I point of the mixed liquid crystal can be raised, and the mixed liquid crystal can be It is possible to prevent the appearance of a smectic phase.

Agent: Patent Attorney Katsutoshi Takahashi

Claims (1)

[Claims] General formula▲ Numerical formulas, chemical formulas, tables, etc.▼ [In the formula, R represents a linear alkyl group having 1 to 10 carbon atoms, X represents a methyl group or a fluorine atom, and Y represents a fluorine atom or a straight-chain alkyl group having 1 to 7 carbon atoms, and ▲ includes mathematical formulas, chemical formulas, tables, etc. All of ▼ are trans (equatorial-equatorial) configurations. ] A compound represented by