JPS59128367A - Cyanophenyl ester derivative - Google Patents

Abstract

NEW MATERIAL:The compound of formula I (R is 1-10C straight or branched- chain alkyl; n is 0 or 1). EXAMPLE:trans-4-(trans-4-Methoxymethylcyclohexyl)cyclohexanecarboxylic acid 4-cyanophenyl ester. USE:A liquid crystal composition. Since the compound exhibits nematic phase over a wide temperature range, it raises the N-I pont of a liquid crystal system at a small dose even if the system has low viscosity. PROCESS:The compound of formula I can be prepared by (1) reducing 4-(trans-4- alkoxymethylcyclohexyl)benzoic acid of formula II in isoamyl alcohol with metallic sodium, (2) reacting the resultant compound of formula III with thionyl chloride to obtain the acid chloride of formula IV, and (3) reacting the product with 4-cyanophenyl derivative of formula V in pyridine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to liquid crystal substances having a wide liquid crystal temperature range and positive dielectric anisotropy, and liquid crystal compositions containing them.

Liquid crystal display elements utilize optical anisotropy and dielectric anisotropy, which are characteristics of liquid crystal materials. TN for liquid crystal display element
There are various types such as (twisted nematic) type, DS (dynamic scattering) type, guest-host type, and DAP type, and the properties required of the liquid crystal material used for each type are different. However, in either method, the liquid crystal material must be stable against moisture, heat, air, light, etc., and it is desirable that the material exhibits a liquid crystal phase over as wide a temperature range as possible. However, at present, there is no single compound that satisfies these conditions, and currently a mixture of several types of liquid crystal substances is used. Recently, there has been a demand for display devices that operate from low temperatures (approximately -20°C) to high temperatures (80 to 90°C), but only combinations of conventionally known compounds have been required. It was difficult to meet such demands.

The compounds of the present invention were designed to meet these demands.

That is, the present invention relates to the general formula (in the above formula, R represents a straight chain or branched alkyl group having 1 to 10 carbon atoms, and represents n1dO or 1). ) Cyclohexanecarboxylic acid-4-cyanophenyl ester rust conductor.

The compound of the present invention has a wide liquid crystal temperature range in the high temperature region.

For example, the C-N point of trans-4-(trans-4-methoxymethylcyclohexyl)-cyclohexanecarboxylic acid-4-cyanophenyl ester is 99.7 to 102.
Since it shows a nematic phase over a wide temperature range, up to temperatures as high as 2°C and N-I point of 288.8°C, adding a small amount of this compound to other liquid crystal systems can produce N without increasing the viscosity. -You can raise your I points.

Next, a method for producing the compound of the present invention will be described. First, 4-(trans-4-alkoxymethylcyclohexyl)benzoic acid produced by a known method is reduced by the action of metallic sodium in an isoamyl alcohol solvent to trans-
4-(trans-4-alkoxymethylcyclohexyl)cyclohexanecarboxylic acid. This is reacted with thionyl chloride to form an acid chloride, and then a 4-cyanphenol derivative is reacted in pyridine to obtain the desired trans-4-(trans-4-alkoxymethylcyclohexyl)cyclohexanecarboxylic acid-4-cyanophenyl ester. is obtained.

If the above is expressed as a chemical formula, (1) (R+n in the above formula is the same as above) The present invention will be explained in more detail with reference to Examples below.

Example 1 [trans-4-(trans-4-methoxymethylcyclohexyl)cyclohexanecarbone-4-
Production of cyanophenyl ester] (1) Production of trans-4-(trans-4-methoxymethylcyclohexyl)cyclohexanecarboxylic acid 4-()trans-4-methoxymethylcyclohexyl)
Benzoic acid 101f isoamyl alcohol 2500 ml
Stir together and heat to 90'C. When 80 da of metallic sodium is added, a violent reaction begins. While continuing to reflux, an additional 12% of metallic sodium was added over 8 hours.
When 02 is added, the reaction solution gradually becomes homogeneous. After the reaction is complete, let it cool to 100°C. Next, in-amyl alcohol is distilled off while adding water. 2000 tel of water was added. Next, add 21 hours of 6N hydrochloric acid to make it completely acidic. The deposited precipitate was filtered, washed with water, thoroughly dried, and used in the next reaction.

(11) Esterified trans-4-(trans-4-methoxymethylcyclohexyl)cyclohexanecarboxylic acid 2.61 (0,
1-Os+1 is added to thiodichloride (01 mol) and heated. It will turn out evenly in about 1 hour, and after heating for another 1 hour,
Excess thionyl chloride was distilled off under reduced pressure, and the remaining oil was trans-4-(),5-x-4-methoxymethylcyclohexyl)cyclohegysancarboxylic acid chloride. Separately, 1.21 (0.01 mol) of 4-cyanophenol was dissolved in 1 otnt of pyridine, the above acid chloride was added thereto, the mixture was stirred thoroughly and left overnight. Add 200 ml of toluene there, and the toluene layer is initially
Wash successively with 6N HCl, then with 2N NaOH aqueous solution, and finally with water until neutral. After drying with sulfuric anhydride), the toluene is completely distilled off under reduced pressure and the remaining crystals are recrystallized from ethanol to obtain the desired trans-4-(trans-4-methoxymethylcyclohexyl)cyclohexanecarboxylic acid. 1.8 g of -4-cyanophenyl ester crystals were obtained. Yield 48%
oC-N point is 99.7-102.2℃, N-I point is 28
The temperature was 8.8°C.

Example 2 In a similar manner, 4-cyano-4'-hydroxybiphenyl was used in place of 4-cyanophenol in Example 1 to produce 4-
() Lance-4-methoxymethylcyclohexyl)cyclohexanecarboxylic acid-4'-cya/-4-biphenylyl ester was produced. C-N point is 188.4-185
．． The 6°C1N-I point was 300°C or higher.

Example 2 (Usage example) Trans-4-propyl-(4'-cyanophenyl)cyclohexane 28% Trans-4-benzene(4'-cyanophenyl)cyclohexane 42% Trans-4-hebutyl-(4'-cyano The liquid crystal composition having a composition of 30% (phenyl)cyclohexane had an N-I point of 52°C, a threshold voltage of 1.58V, and a saturation voltage of 2.12V. The viscosity was 28 cp at 20°C.

To 95 parts of this liquid crystal composition was added the trans-transformer prepared in Example 1.
4-(trans-4-methoxymethylcyclohexyl)
The N-I point of the nematic composition containing 5 parts of cyclohexanecarboxylic acid-4-cyanophenyl ester is 60°C.
, the L threshold voltage was 1.55V, and the saturation voltage was 2.80V.

The viscosity was 25 cp at 20°C.

that's all

Claims (2)

[Claims] (1) A trans-
4-(trans-4-alkoxymethylcyclohexyl)cyclohexanecarboxylic acid-4-cyanophenyl ester derivative. (2) A trans-
1. A liquid crystal composition comprising at least one component of a 4-(trans-4-alkoxymethylcyclohexyl)cyclohexanecarboxylic acid-4-cyanophenyl ester derivative.