JPS5944332A - 3,4-dichloro-bicyclohexylbenzene derivative - Google Patents

Abstract

NEW MATERIAL:The 3, 4- dichloro-1-[ trans-4'-( trans-4''-alkylcyclohexyl ) cyclohexyl]benzene of formula I (R is H, 1-10C alkyl or alkoxy). USE:A liquid crystal compound exhibiting liquid crystal phase over a wide temperature range and having low viscosity. PROCESS:A Grignard reagent derived from 1-bromo-3,4-dichlorobenzene and metallic Mg is made to react with 4-(trans-4'-alkylcyclohexyl)cyclohexanone. The resultant compound of formula II is dehydrated with KHSO4, and the obtained compound of formula III is dissolved in toluene and catalytically reduced in the presence of Raney Ni to obtain the objective compound of formula I .

Description

DETAILED DESCRIPTION OF THE INVENTION Is the compound C71,11 of the present invention? 1. Concerning a novel liquid crystal substance exhibiting anisotropy and a liquid crystal composition containing the same.

Liquid crystal display elements utilize the optical anisotropy and dielectric anisotropy of liquid crystal materials, but depending on the display format, TN
type (twisted nematic type), DS type (dynamic scattering 1I11,
type), guest/host type, ]) AP type, etc. 117 each
The method is divided into 1 types, and each method differs depending on the use Vr and the properties t of the suitable liquid crystal material. However, all liquid crystal materials have one thing in common: they must be stable against moisture, air, heat, light, etc., and they are required to exhibit a liquid crystal phase over as wide a temperature range as possible, centered around room temperature. There are others. However, at present, there is no compound that satisfies this requirement, and the current situation is to use liquid crystal compositions obtained by mixing several types of liquid crystal compounds and non-liquid crystal compounds. In particular, recently there has been a demand for liquid crystal display elements that operate in a wide temperature range such as -20°C to 80°C.In order to satisfy this demand, viscosity, especially at low temperatures, An effective method is to lower the viscosity.However, in general, those with a high clearing point (N-1 point) have a high viscosity, and those with a low viscosity1, such as argylphenyl clohexane derivatives, are transparent. The score is low.

An object of the present invention is to provide a crystalline compound having a high N-1 point and low viscosity that meets such requirements.

That is, the present invention provides 3,4-
dichloro-1-[trans-4'-()trans-4'
〃-alkylcyclohexyl)cyclohexene)al in Hensen.

The compound of formula (1) of the present invention exhibits a liquid crystal phase over a wide temperature range and has low viscosity, so it can be effectively used to meet the above requirements. For example, %3.4-dichloroo-1-(
) lance-4'-() lance-41-pendelcyclohexyl)cyclohexyl J benzene d4, crystal-nematic point E, (1,4°C.

It exhibits a wide nematic liquid crystal phase with a nematic clearing point of 103.4°C, and is used as a component of a low-viscosity liquid crystal composition having a wide liquid crystal temperature range.

First, the method for producing the compound of the present invention will be described. t-
ti' 1-Flomo3. 4-dichlorobenzene is heated to react with metallic magnesium to obtain a Grignard reagent,
By reacting this with 4-(trans-4'-alkylcyclohexyl)cyclohekylinone, 3,4-dichloro-
1-44,'-()lance-45-alkylcyclohexyl)cyclohgiven]'-ol]bense/. Next, this is dehydrated with potassium hydrogen sulfate to obtain 3,4-dichloro-]-I,4'-()lans-41-alkylcyclohexyl)cyclohexen-1/-yl]benupine. This was dissolved in toluene and subjected to )λ catalytic reduction in the presence of Raney nickel to obtain the desired 3,4-dichloro-1
-[trans-4'-(trans-41-alkylcyclohexyl)cyclo]ben7ine 1).

The above is expressed as a chemical formula as follows.

(1) The following examples provide further details regarding the compounds of the present invention η(B
K.Explain.

Example 1 (3,4-dichloro-1-[trans-, L
l ()Lance-41-pendelcyclohexyl)cyclohexyl] Manufacture of ben7ane] 1.2 F (0,040 mol) of magnesium section was added to 5
45.4-dichlorobromopenguin 11.1 ? A solution of ((,1,(149 mol)) dissolved in tetrahydrofuran was heated to a reaction temperature of f, 31) to 35°C in a N2 stream, and the reaction was carried out slowly while stirring. After 3 hours, the magnesium dissolves and becomes homogeneous, producing S, a-cyclophenylene A and magnesium furomide.
'-pendelcyclohexyl)cycloto44.1-None I CLOF (0,040 mol) was dissolved in tetrahydrofuran to make 50 ml, and the reaction temperature was adjusted to 50 ml.
Remove as quickly as possible while maintaining the temperature at ~10°C. After simple F,
Incubate at 35°C and stir for 50 minutes, then add 3N salt (i'
Add <50 ml. Transfer the reaction solution to a separating funnel for 20 minutes.
After extraction three times with 0 yn. of toluene, the combined toluene layers were washed with water until the washings became neutral, and the toluene was distilled off under reduced pressure. The remaining oil is 3,4-dichloro-1
-(4'-()lans-41-be/brunchlohexyl)cyclohexen-17-ol]ben7ine. To this, add 62 υL of potassium hydrogen sulfate to 160 υL in a N2 stream.
Dehydrate at ℃ for 2 hours.

After cooling, 200 d of toluene was added, the potassium hydrogen sulfate was separated, and the toluene layer was washed with water until the washing liquid became neutral. Next, toluene was distilled off under reduced pressure, and the remaining oil was recrystallized from acetone to obtain 3,4-dichloro-1-
(4'-(trans-4Lpentyl/chlorohequinyl)/
Chlohexe/-1'-yl]benzene.

This product (1.8 F) was dissolved in 200 ml of toluene, 1.01 ml of Raney nickel catalyst was added, and catalytic reduction was carried out at room temperature and pressure. The reaction was followed by gas chromatography,
The process ended when the raw material disappeared. After the catalyst was separated from the furnace, the solvent was distilled off under reduced pressure, and the residue was repeatedly recrystallized with toluene to obtain the desired 3.4-:)chloro-1-[trans-4'-()
lance-41-pentylcyclohexyl) (merge: five-o-tate-tate-cyclohexyl) benzene was obtained. Yield tA0.
1 f oC-11 point is 5014℃, N-e point is l O
The temperature was +3.4°C.

Other substituents can also be produced in the same manner as in Example J.

Implementation 12 Li-2 Trans-4-gr1biA-(4'-/-1 nophenyl)/Clohairin 28%□Trans-4-
Pliers 8-(4'-/anofukol) cyclohexene
42% trans-4--＼buf/l,-(4/
The nematic temperature range of the liquid crystal composition of 30% -anophenyl) is 3°C to 52°C. Δεe +11.8, threshold voltage 1.5V, saturation GtT, J-1-1rJ, 2. OV, 20'
The viscosity at C is 23 cp.

The nematic liquid crystal of a liquid crystal composition prepared by adding 11 parts of Example 1 of the present invention to 90 parts of this liquid crystal composition spreads over a nematic liquid crystal temperature range of 1-3 to 55.1°C and has a viscosity of 27°C at 20°C.
p, Δg#-j, 10.6, threshold voltage is 1.5v%, saturation voltage is 2. It was Ov. The temperature range can be expanded without increasing the viscosity, and the driving voltage is not high.

1L above

Claims (1)

[Scope of Claims] 5,4- represented by (in the above formula, R represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group)
dichloro-"-[trans-a,'-()trans-4'
-alkylcyclohexyl) cyclo△eicyIL/)benC0(2) 3 represented by the general formula (in the above formula, R represents a hydrogen atom or an alkyl group or an alkokino group having L-10 carbon atoms) , 4-
dichloro-1-[trans-4'-(+-trans-4
A liquid crystal composition containing at least one type of '-alkylcyclohexy/-)cyclohexyl]benzene.