JPS5998065A - Pyrimidine derivative - Google Patents

Abstract

NEW MATERIAL:The 5-( trans-4'-alkylcyclohexyl )-2-(4''-alkyloxyphenyl)pyrimidine of formula I (R1 and R2 are 1-10C alkyl). EXAMPLE:5-(trans-4'-Hexylcyclohexyl)-2-(4''-butyloxyphenyl)pyrimidine. USE:A liquid crystal substance having extremely high anisotropy of refractive index, relatively broad liquid crystal temperatue range, and excellent stability. PROCESS:The compound of formula I can be prepared by reacting the compound of formula II with the compound of formula III in the presence of CH3ONa, reacting the resultant compound of formula IV with POCl3 to obtain the compound of formula V, and finally, treating the product with H2. Since the objective compound has excellent compatibility with other liquid crystal substances, it is effective to improve the response, contrast, and sharpness of the substance, and raise the N-I point remarkably by the addition of a small amount of the compound.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel organic compound, and more particularly to a novel liquid crystal compound useful as a component of a liquid crystal material.

As is well known, liquid crystal materials can be used for display devices that use twisted liquid crystal alignment (so-called TN cells), as well as display devices that apply the guest-host effect of liquid crystal materials or liquid crystal mixtures containing appropriate dyes. Furthermore, DS type display elements that utilize the dynamic scattering effect of liquid crystals, DAP type display elements that utilize cholesteric-nematic phase transition, and the like are widely used. As a single compound, these liquid crystal materials have various t# characteristics, that is, liquid crystal temperature range, operating voltage,
The response performance etc. do not make it suitable for practical use, and in practice, liquid crystal compounds that can be used to a certain extent are obtained by mixing several types of liquid crystal compounds. The present invention provides a compound useful as a component of such a practical, excellent and stable liquid crystal composition.

That is, the present invention provides 5-(trans-4'-alkylcyclohexyl)-2-(4"-alkyloxyphenyl ) is a pyrimidine.

The compound of the formula (1) of the present invention is a liquid crystal compound with extremely large anisotropy of refractive index and excellent stability over a considerably wide liquid crystal temperature range, as shown in the examples below.

The compound of the present invention has excellent compatibility with other liquid crystal compounds, such as biphenyl-based, ester-based, azoxy-based, cyclohexanecarboxylic acid ester, phenylcyclohexane-based, phenylmetadioxane-based, phenylpyrimidine-based, etc. By mixing it with one type or several types of liquid crystal compounds, the response characteristics, contrast, and sharpness can be improved, and the addition of a small amount can significantly increase the N-I point. It has an effect.

Examples of suitable compounds of formula (1) include the following.

5-(trans-4'-7'rovylcyclohexyl)-
2-(4″-propyloxyphenyl)pyrimidine.

5-(trans-4'-propylcyclohexyl)-2
-(4"-butyloxyphenyl)pyrimidine.

5-() lance-4/70 pylcyclohexyl)-
2-(4“-pentyloxyphenyl)pyrimidine.

5-(Trysu-47-bropylcyclohexyl)-2
-(4″-1-xyloxyphenyl)pyrimidine.

5-() lance-47-propylcyclohexyl)-2
-(4"-hebutyloxyphenyl)pyrimidine.

5-(trans-4'-butylcyclohexyl)-2-
(4“-propyloxyphenyl)pyrimidine.

5-C trans-4'-butylcyclohexyl)-2-
(4”-butyloxyphenyl)pyrimidine.

5-() lance-4'-butylcyclohexyl)-2-
(4“-pentyloxyphenyl)pymidine.

5-() lance-47-butylcyclohexyl)-2-
(4“-hexyloxyphenyl)pyrimidine.

5-(trans-47-butylcyclohexyl)-2-
<e-hebutyloxyphenyl)pyrimidine.

5-(trans-47-pentylcyclohexyl) ~2
-(4"-propyloxyphenyl)pyrimidine.

5-(trans-4'-pentylcyclohexyl)-2
-(4"-butyloxyphenyl)pyrimidine.

5-(trans-4'-pentylcyclohexyl)-2
-(e-pentyloxyphenyl)pyrimidine.

5-(trans-4'-pentylcyclohexyl)-2
-(4“-hexyloxyphenyl)pyrimidine.

5-(trans-4'-pentylcyclohexyl)-2
(4“-hebutyloxyphenyl)pyrimidium
hmm .

5-() lance-4'-hexylcyclohexyl) -
2-(4''-7''ropyloxyphenyl)pyrimidine 2 5-(4'-hexylcyclohexyl),
-2-(4"-butyloxyphenyl)pyrimidine.

5-() lance-4'-hexylcyclohexy#)-2
-(4"-pentyloxyphenyl)pyrimidine.

5-() lance-4'-hexylcyclohexyl)-2
-(4"-hexyloxyphenyl)pyrimidine.

5-() lance-4'-hexynecyclohexyl)-2
-(4"-hebutyloxyphenyl)pyrimidine.

5-(trans-4'-hebutylcyclohexyl)-2
-(4"-propyloxyphenyl)pyrimidine.

5-() lance-4'-hebutylcyclohexyl)-2
'-(4"-butyloxyphenyl)pyrimidine.

5-() lance-4'-hebutylcyclohexyl)-2
-(4"-pentyloxyphenyl)pyrimidine.

5-()2-4'-hebutylcyclohexyl)-2
-(4"-hexyloxyphenyl)pyrimidine.

5-() lance-4'-hebutylcyclohexyl)-2
-(4"-hebutyloxyphenyl)pyrimidine.

Next, the method for producing compound (1) of the present invention will be explained in detail.

′=! The outline of the reaction formula is shown below:■( ]H 2H5 C2)Is (v) *(R1 in the above formula
, R2 are the same as above) ■ Using a commercially available product of -4-4-alkyloxycyanophenyl GI) as a starting material, it was dissolved in alcohol and toluene, and reacted with hydrochloric acid gas to form an imide ether hydrochloride derivative GI [ ).

Next, this is reacted with an ammonia and ethyl alcohol solution to obtain an amidine hydrochloride derivative Φ゛).

On the other hand, 4-alkylcyclohexanone (■) produced by a known method and cyanacetic acid ester are subjected to a condensation reaction using a catalyst such as ammonium acetate or pyridine-acetic acid, and the water produced during the reaction is converted into benzene, toluene, or xylene. 4-alkylcyclohexylitine cyanacetate ('D t
(R.Next, compound (Vl)f: J, A, M
arshau, RoD.

Carrou, J. Org. Chem., 80.
2748 (1965) et al. to give 4-alkylcyclohexylcyanoacetate (VID t
mru.

Subsequently, Cimarron Kishi conductor (VIi
+) is obtained. The obtained compound is a mixture of cis and trans isomers, and this isomer can be separated by simply recrystallizing from a well-known solvent such as ethyl alcohol. In the present invention, the target compound has a trans structure. Next, by esterifying the trans form of the compound G'll, malonic acid diethyl ester 8 compounds (IX
) get k.

Next, compound (IV) which was mentioned in A4) and compound ■
and cyclization reaction in the presence of sodium methoxide to obtain a 2,5-substituted-4,6-cyhydroxypyrimidine derivative α)'? ! :obtain. Next, compound α) was chlorinated using phosphorus oxychloride to give 2°5-111-2JU
,,a, 6-dichloropyrimidine inducer 1)
get. Finally, compound 1) is reduced with hydrogen using palladium carbon as a catalyst to obtain the target compound (1).

Hereinafter, this compound will be explained in more detail with reference to Example F4.

Example 1 (5-, (trans-4'-hexylcyclohexyl)
2 Synthesis of (,i//-butyloxyphenyl)pyrimidine] (1st stage) Commercially available 4-butyloxybenzonitrile 87, 39 (
0,499mo7) to anhydrous methanol 20.89 (
0,650 mo/L) and 50 srJ of toluene, stirred at -5°C, replaced with nitrogen, and added 25 g of hydrochloric acid gas to 50 srJ of toluene.
The mixture was heated for 0 minutes, and stirring was further continued at -5°C for 6 hours. The reaction mixture was allowed to stand at -20"C for 2 days to precipitate crystals. 80 ml of ether was added and filtered for 70 minutes to dry the crystals. 100.91 (yield 88%) was obtained.

(2nd stage) 4-butyloxyphenylimide (0.0 4 1 mol) I/C7 ammonia ethanol Jv B solution (1 5.9 wt%) 8 5
nl was added, stirred at 30°C for 6 hours, further left at room temperature for 2 days, filtered, ethanol in the ν solution was distilled off, and the precipitated crystals were dried. -Butyloxyphenylamidine hydrochloride 8.9 g (yield 95%) was obtained.

(Third stage) 4-hexylcyclohexanone 91,Ig (0.5
mot) (!Nijian 1 “C Shun Ethyl Ester 5
6,59 (0.5 mot) and ammonium acetate 1,59 (0.02 mot)
'd: Mixed and reacted under reflux using benzene as a solvent until no water produced by the reaction was distilled out. After the reaction π-wintered, the benzene solution was left to cool at room temperature 1. From the benzene solution, ammonium was removed by IP from the benzene solution, and the benzene was then distilled off. Ethyl acetate 1 1 5.1 gC (yield 83%) was obtained.

(4th stage) K: 8 3.2 g (0.8 m
ol) in 200 r/ml of ethyl alcohol, and to this was added 7.6 t/(0.0 t/ml) of sodium borohydride.
2 mot) to ethyl alcohol 200 1rt
A solution dissolved in f was added dropwise at 0°C. After the addition was completed, the mixture was further stirred using a Muroko M. After the reaction is complete, pour the reactant into ice water at 1,000 ml.
+/.

It was added to a mixture of 200 ml of concentrated hydrochloric acid and stirred vigorously.

The precipitated oil was extracted with 100 ml of toluene. The toluene extract was washed with 5% sodium bicarbonate solution and then with water, and then the solvent was distilled off. Distill the residue under reduced pressure to obtain 4-hexylcyclohexyl cyanine vinegar rR.
Ether ester r2.91c (yield: 87%) was obtained.

(5th stage) 55.99 (0.2 mo) of the obtained 4-hexylcyclohexyl cyanacetic acid ethyl ester was mixed with 45.017 (0.8 r++ot) of potassium hydroxide and 50 πt of water.
The mixture was dissolved in 200 ml of ethyl alcohol and reacted for 10 hours under reflux. After the reaction was completed, the reaction solution was cooled, 1000 ml of water was added, and then 10 ml of concentrated hydrochloric acid was gradually added. The precipitated crystals were filtered and recrystallized from ethanol until a single peak was observed in gas chromatography, yielding 910.8 g of trans-4-hexylcyclohexylmalone t.

(Sixth stage) To the obtained trans-4-hexylcyclohexylmalone i'IQ 10.81 (0.04 mot) were added 26 g of ethyl alcohol and 3 pal of sulfurized (.4 mol), and the mixture was heated under reflux.
Time reacted. Cool the reaction solution, add 100 ml of water, and add 15 s of toluene and 10 ml of n-hebutane.
Mixing of A7t: Extract with a volume of 7 and 2N.

- Washed with a water bath solution and then with water, and then the solvent was distilled off. The residue was distilled under reduced pressure to give trans-4-hexylcyclohexylmalone r'+'g diethyl ester lO,7It' (1jSlj=82%.

Boiling point 180-188°C74t:! m'k1g) was obtained.

(2i',' 7 steps) Metallic sodium 1.89 (0,057mol>'fr
: 4-Butyloxyphenylamidine borate 3, which was added to anhydrous methyl alcohol 28TIt and converted into sodium methoxide, was then converted into 4-butyloxyphenylamidine borate 3 in the second stage while cooling with ice.
．． 53 furnace ((1015 mol) and trans-4-hexylcyclohexyl malonic acid diethyl ester 5.0
Add 0 f/ (0,015 rnot), wash with chill alcohol and dry to obtain 5-(trans-4'-hexylcyclohexyl)-2-(4"-butyloxyphenyl)-4,6-cyhydroxypyrimidine. 4.6 (/ (
A yield of 70%) was obtained.

(8th stage) Obtained 5-() lance-4'-hexylcyclohexyl)-2-(4"-7" thyloxyphenyl)-4,6
-cyhydroxypyrimidine 4.6g (0,011mol
) was added with 22 ynl of phosphorus oxychloride and 8 yil f of N,N-diethylaniline, and after refluxing for 20 hours, the excess phosphorus oxychloride was distilled off and poured into 200 d of 10% aqueous sodium hydroxide solution while still hot, and then poured into 50 t of toluene.
ttt extraction, the toluene layer was washed with 20% hydrochloric acid and water, recrystallized from a mixed solvent of ethyl alcohol-heptane, and dried to give 5-(trans-4'-hexylcyclohexyl)-2- (e-1 thyloxyphenyl)-4,6-dichloropyrimidine a, aiv (yield 6
6%, melting point 85°C).

(9th stage) K<j hlic 5- () lance-4'-hexylcyclohexyl) -2-(4"-butyloxyphenyl') -4,' 6-dichloropyrimidine 8.3 g
(0,007 mol) 14% magnesium 1.2
f.

0.88 g of palladium carbon (5%), 8 Oat of ethyl alcohol, and 3 liters of water were added, and hydrogen gas was absorbed at room temperature until saturated. The reaction product was filtered and the residue was washed with toluene, and the toluene layer and furnace solution were distilled off, dissolved in 50πt of toluene, washed with a 10% sodium chloride water bath, and then washed with water and a neutral sieve. Afterwards, toluene was distilled off and recrystallized from a mixed solvent of ethyl alcohol and heptane to obtain the final target product, 5-(trans-4'-
Hexylcyclohexyl)-2-(4"-butyloxyphenyl)pyrimidine 1.80f (yield 64%) was obtained. This compound showed a smectic liquid crystal phase and its C-8
The point was 76°C, and the SI point was 198°C. In addition, the elemental analysis value is Example 2 (Essential); 1 Example 1) C31iy % CN 24->4't ('
AKia, ' , below I, )CJlnA section ← CN
86 praise j5C, H, 5-(瀉(death CN
Part 25 C51111! ν0□□□))CN Liquid crystal type 2H skin consisting of 15 parts! 1 course A's l'J-4 point is 72.1
°Cl2O° (viscosity at j η2oi'J: 27.8
cp, K〆5kanisotropy △ε is 11.6 ("εz=1
6.1; ε soil - 4.5) Deko Dokura 4.5! ,? -10μ
The threshold voltage of the TN cell inserted into η7 is 1.75.
'V, saturation voltage is 2.43V, S,a, tri index ascending Δn is 0.139 (n8=1.682.n,)=1.
498).

10 parts of the compound 5-(trans-4'-hexylcyclohexyl)-2-(4"-butyloxyphenyl)pyrimidine of the present invention 1y obtained in Example 1 was added to 90 parts of this liquid crystal composition (1N A). The N-I point of the liquid crystal composition was 82.8.
℃, η2o is 31.4cp△ε is 10.6(ε
/-14,8,ε engineering=4.2).

The threshold voltage is 1.73V, the saturation voltage is 2.47V, △n (d o, 144 (n 6 = 1.689
+ n□ = 1.495) 4' go up/this. Thus, it can be seen that the compound of the present invention has a very large value of Δn. .

(△nil for this compound alone: room, 411%, solid (ilj fixed difficulty Mii).

that's all

Claims (2)

[Claims] (1) 5-(trans-4'-alkylcyclohexyl)-2-(4"-al'kyloxy phenyl)pyrimidine. (2) 5-(trans-4'-alkylcyclohexyl) 72- (4"-furkyloxyphenyl) represented by the general formula (in the above formula, R1t R2 represents an alkyl group having 1 to 1 o carbon atoms)
A liquid crystal composition containing at least one pyrimidine.