JPS5965063A - Octadecahydro-p-terphenylcarboxylic acid 3-cyanophenyl ester - Google Patents

Abstract

NEW MATERIAL:The compound of formula I (R is H or 1-10C alkyl). EXAMPLE:trans-4''-Propyl-trans-octadecahydro-p-terphenyl-trans-4-carbo xylic acid 3-cyanophenyl ester. USE:A liquid crystal composition having high liquid crystal temperature range and nevertheless low viscosity. PROCESS:The compound of formula I can be prepared by (1) reacting bromobenzene with metallic magnesium, (2) reacting the resultant phenyl magnesium bromide with the compound of formula II to obtain the compound of formula III, (3) hydrogenating the product using Raney-Ni, (4) halogenating and then cyanizing the obtained compound of formula IV with cuprous cyanide to obtain the compoud of formula V, (5) hydrolyzing the compound in a mixture of an aqueous solution of potassium hydroxide and diethylene glycol, (6) reducing the obtained compound of formula VI with metallic sodium, and (7) converting the product to an acid chloride and reacting with 3-cyanophenol.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel liquid crystal material exhibiting a liquid crystal phase over a wide temperature range and having weak positive dielectric anisotropy, and to a liquid crystal composition containing the same.

Display elements using liquid crystals have come to be widely used in watches, calculators, etc. This liquid crystal display element utilizes the properties of optical anisotropy and dielectric anisotropy of liquid crystal materials, and liquid crystal phases include nematic liquid crystal phase, smectic liquid crystal phase, and cholesteric liquid crystal phase, among which nematic liquid crystal is used. The one that has been put into practical use is the most widely used. That is, these types of K include TN (twisted nematic) type, DS (dynamic scattering type), guest Φ host type, DAP type, etc., and the properties required of the liquid crystal material used for each type are different.

However, even if they are washed, these display elements [(It is desirable that the liquid crystal material used be one that exhibits a liquid crystal phase over as wide a range as possible in nature, but at present there is no single material that satisfies such conditions. Currently, products that can withstand practical use are obtained by mixing several types of liquid crystal substances or non-liquid crystal substances.In addition, these substances have resistance to moisture, light, heat, air, etc. Needless to say, K must be stable, and it is desirable that the threshold voltage and saturation voltage necessary to drive the display element be as low as possible, and that the viscosity of K be as low as possible in order to increase the response speed. In order to widen the liquid crystal temperature range toward higher temperatures, it is necessary to use a liquid crystal substance with a high melting point as a component, but liquid crystal substances with a high melting point generally have a high viscosity (and therefore, the liquid crystal composition containing it also has a high viscosity. Therefore, the response speed of liquid crystal display elements that can be used up to high temperatures, for example around 80C, tends to be significantly slow, especially at low temperatures. The present invention was achieved by finding a liquid crystal material with low viscosity.

That is, the present invention provides trans-4"-alkyl-trans-octadecahydro-P-terphenyl" trans-4- A carboxylic acid-3-cyanophenyl ester and a liquid crystal composition containing the same.

The compounds of the invention have a high clearing point, for example trans-4"-propyl-trans-octatecahydro P-terphenyl-trans-4, which is one of the compounds of the invention.
The c-s point of -carboxylic acid-3-Schiff/phenyl ester is 110.5C.

8-N point is 194. Oll:', N-N point is 235.
0t? It exhibits a liquid crystal phase over a wide temperature range, and by adding it as a component of the composition, the viscosity of the liquid crystal composition can be increased to ~
You can raise the transparent point without increasing it. Further, although the dielectric anisotropy value of the compound of the present invention is approximately +1, the threshold voltage and saturation voltage of the composition are not significantly changed. Also moisture,
It also has good stability against heat, light, etc. There is also a possibility of application to the two-frequency method.

Next, a method for producing the compound of the present invention will be described. First, phenylmagnesium glymide is produced from bromobenzene and metallic magnesium, and it is reacted with 4-(trans-4'-alkylcyclohexyl)cyclohexane to produce 4'-(1
-rance-4'-argylcyclohexyl)cyclohexan-1-ol-benzene G). Next, this is dehydrated using potassium hydrogen sulfate as a catalyst to produce 4" () lance-
4”-alkylcyclohexyl)cyclohexene-1′
-yl-benzene [phase], which was then hydrogenated using a Raney nickel catalyst to obtain trans-4'-(trans-
4”-alkylcyclohexyl)cyclohexylbenzene (IV) is obtained, which can also be obtained by hydrogenation of (ID) directly using Raney nickel. The compound is then treated with iodic acid or periodic acid. By halogenating with etc., 4-[trans-41-alkylcyclohexyl)cyclohexyl]halogenobenzene M
If this is cyanated with a cyanide solution, 4-[trans-4'7(trans-4'-alkylcyclohexyl)cyclohexyl]benzonitrile is obtained.

Next, this compound (1) was hydrolyzed in an aqueous potassium hydroxide solution-diethylene glycol system, and 4-[trans-
4'-(+-lance-41-alkylcyclohexyl)
Manufactures cyclohexyl]benzoic acid. This benzoic acid derivative is reduced with sodium metal in isoamyl alcohol to give trans-4''-alkyl-trans-octadecahydro-p-terphenyl-trans-4-carboxylic acid.

This was converted into acid chloride with thionyl chloride, and then 3-
When cyanphenol is reacted with pyridine, the desired trans-4'-alkyl-trans-octadecahydro-p-terphenyl-trans-4-carboxylic acid-3 is obtained.
-Cyano heptadyl ester (I) is obtained. When the above is represented by a chemical formula, the compound of the present invention will be explained in more detail with reference to Examples below.

Example 1 [Production of trans-4'-propyl-trans-octadecahydro-p-terphenyl-trans-4-carboxylic acid-3-cyanophenyl ester] Magnesium shavings 3.6# (0,148 mol) Put three [-1] into a flask and add fromobenzene 23,2,? (
0,148 cells) dissolved in tetrahydrofuran in a N gas stream, keeping the reaction temperature at 30 to 35 tZ', and slowly dropping it dropwise while stirring. The reaction will occur, and in 3 hours the magnesium will dissolve and become uniform. to produce phenylmagnesium bromide. To this 4-() Lance-4'
-Propylcyclohexy/L/)cyclohexanone 26
．． Dissolve 2 g (0,118%) in tetrahydrofuran and give 50 m/! While keeping the reaction temperature below 10℃, drop the mixture as quickly as possible. After dropping, add 35 tl'
Stir for 30 minutes, then add 3N hydrochloric acid to
Add. Transfer the reaction solution to a separating funnel and add 10% of n-hebutane.
After extraction three times at 0 m, the combined n-hebutane layers are washed with water until the washings become neutral, and then the n-hebutane is distilled off under reduced pressure. The remaining oil is [4'-r) lance-4''-
proylcyclohexyl)cyclohexane-1'-ol]benzene, and potassium hydrogen sulfate 19II
was added and dehydrated for 2 hours at 17 Or in a N2 stream. After cooling 2
After adding 0 Qd of n-hebutane, the potassium hydrogen sulfate is removed by a furnace, and the n-hebutane layer is washed with water using a separating funnel until the washing liquid becomes neutral. Next, T1-hebutane was distilled off under reduced pressure, and the remaining oil was recrystallized from n-hebutane and acetone to obtain (4-(trans-42-propylcyclohexyl)cyclohexene-1'74)benzene. This 7.511 was dissolved in 500 ml of ethanol, 3.2 g of Raney nickel catalyst was added, and catalytic reduction was carried out at 50 C under normal pressure with hydrogen. Both the raw material and the product were traced by gas chromatography, and it was confirmed that the raw material had disappeared. The reduction reaction was terminated after 8 hours.The amount of hydrogen absorbed at this time was 800.
It was Go. After removing the catalyst, the solvent was distilled off under reduced pressure, and the remaining crystals were recrystallized from ethanol to obtain [trans-4'-(
) lance-4A'-propylcyclohexyl)cyclohexyl]benzene was obtained. Add 1.4g of this to 150d of vinegar
Dissolve K, 0.9% of pure water, 1.0% of concentrated sulfuric acid, 0.0% of iodic acid.
A mixture of 20g of iodine, 5oII of iodine, and 0.4 of carbon tetrachloride was refluxed at 80C for 5 hours. The reaction solution was cooled, the precipitated crystals were separated in a furnace, and the product obtained by recrystallizing from this crystalline n-hebutane was 4-[trans-4'-(trans-4
"-propylcyclohexyl)cyclohexyl]iodobenzene ω. This substance exhibits a liquid crystal state and is U-8
The point was 119.0C8N was 139.2tl', and the N-I point was 189.2tl'. This 1.21 is N, N'
-Dissolved in 50 me of dimethylformamide, added 0.63 y of cupric cyanide, and reacted at 130C for 4 hours.

Add n-heptane 100+d, transfer to a separating funnel, and add 3
The solution is separated with 0 thiammonium water, then washed with water, washed with 6N hydrochloric acid, and further washed with water until the washing solution becomes neutral. The solvent was distilled off under reduced pressure and the product obtained by recrystallization from n-hebutane was 4-C,+-trans-4'-(trans-4"-propylcyclohexyl)cyclohexyl]benzonitrile. Yield: 0 .4g, yield is 4 for cyanation reaction
5%, and the C-S point &-1731c, and the S-N point are 81.1tl? , N-I point c 242.5 c tea ivy.

5 g of 4-[trans-4'-(trans-47-furobylcyclohexyl)cyclohexyl]benzonitrile obtained as above and 5 g of potassium hydroxide were added to 10-
diethylene glycol 100 with a solution dissolved in water.
Add meIC and heat in flask at 200C for 7 hours.

After the reaction is completed, the mixture is allowed to cool and 50 g of 5N HCl and 100 g of water are added. Filter the precipitated crystals and wash thoroughly with water. The 4-[trans-4'-() obtained in this way
Lance-4''-propylcyclohexyl)cyclohexyl]benzoic acid (V][): 3 # is stirred with isoamyl alcohol 1500- and heated to 90C.

When 10g of metallic sodium is added to it, a violent reaction begins. While continuing to reflux, an additional 80 g of metallic sodium was added over 3 hours. The reaction solution gradually becomes homogeneous.

After the reaction is completed, it is allowed to cool to 100C. Isoamyl alcohol is distilled off while adding water little by little. Water is 1.51
added. After adding 1 portion of 6N hydrochloric acid to make it completely acidic, the precipitate was filtered and washed with water. It was recrystallized with acetic acid to give trans-4-propyl-trans-octadecahydro-
P-delphenyl-trans-4-carboxylic acid (2) was obtained. Yield 1.9. Sl', yield 63 yen. This one also exhibits liquid crystallinity, and its C-S point is about 170C, and the 8-N point is 282C.
, N-N point was 290-300C (with decomposition).

The carboxylic acid ωi) 0.5P prepared in this way is heated to 80C with thionyl chloride 10-.

The reaction solution became homogeneous in 2 hours, and the reaction was continued for an additional 1.5 hours. Excess thionyl chloride is distilled off under reduced pressure rc. The oil that remains is the acid chloride. Separately, 0.5 g of 3-cyanophenol was dissolved in 20 grams of pyridine, an acid chloride was added thereto, 100 grams of toluene was added, and the mixture was allowed to stand overnight. First, remove the toluene layer in a separatory funnel with 6N hydrochloric acid.
It is then washed with 2N caustic soda solution and finally with water until neutral. After drying it over anhydrous sodium sulfate, the toluene layer was distilled off under reduced pressure.

The precipitated crystals were recrystallized from ethanol and then from acetone to obtain the desired trans-41-propyl-trans-octadecahydro-p-terphenyl-trans-4-carboxylic acid-3-cyanophenyl ester. Yield: 0.4g, Yield: 31t, C-S point: 110.5t
l? , S-N point is 194. OC, N-N point is 235
．． It was 0tl'.

In a similar manner, 4-[trans-4'-() lance-4''
4-[trans-4'-() with another alkyl group in place of cyclohexanone (-furoylcyclohexyl)
Other desired products of formula (1) can be obtained in exactly the same manner using lance-4''-alkylcyclohexyl)cyclohexanone.

Example 2 (Application example) Trans-4-propyl-(4'-cyanophenyl)cyclohexane 28% trans-4-pentel-(4'-cyanophenyl)cyclohexane
42 Thitrans-4-hebutyl-(4'-cyanophenyl)cyclohexane 30 The nematic clearing point of the liquid crystal composition with the following composition is 52C. When this liquid crystal composition was encapsulated in a TN cell (Twisted Neat Cell) K with a cell thickness of 1077 m, the operating threshold voltage was 1.53 V.
The saturation voltage was 2.12V. Also, the viscosity is 23 at 20C.
It was an ep.

Trans-4 prepared in the example was added to 97 parts of this liquid crystal composition.
'-Propyl-trans-octadecahydro-P-terphenyl-trans-4-carboxylic acid-: Nematic clearing point f- of a nematic composition containing 3 parts of 3-cyanophenyl ester! 57. T? ,L key i)j,
cat 1.65V, Ki sum N pressure c2, 30 V te, f-, ivy. Also sticky 1! l[20Cte260p.

that's all 477-

Claims (1)

[Scope of Claims] trans-4'-alkyl-trans-octadecahydro-p-terphenyl-trans-4 represented by υ (in the above formula, R represents hydrogen or an alkyl group having 1 to 1 o carbon atoms) -Carboxylic acid-3-cyanophenyl ester. (The middle hole in the above formula represents hydrogen or an alkyl group having 1 to 1 o carbon atoms) A liquid crystal composition containing at least one phenyl ester.