JPH0676352B2 - Method for producing bis (p-aminocumyl) benzenes - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for producing bis (p-aminocumyl) benzenes, and more particularly, to a high yield of bis (p-aminobenzene) from diisopropylbenzenedicarbinols and anilines.
Aminocumyl) benzenes.

Technical background of the invention and its problems Bis (p-aminocumyl) benzenes are polyamides,
It is a compound useful as a raw material for synthetic resins such as polyimide, polyamide-imide and epoxy, a resin additive and a dye.

Regarding the method for synthesizing the bis (p-aminocumyl) benzenes, for example, US Pat. No. 3,267,145 discloses diisopropylbenzenedicarbinols (α, α′-dihydroxydiisopropylbenzenes) as raw materials and aniline. A method of reacting and is used as an activated clay catalyst is disclosed. However, in this method, the target compound bis (p-aminocumyl) benzenes cannot be obtained in a high yield, and particularly when the dicarbinols are m-forms, the yield is extremely lowered. There was a problem.

Also, West German Patent No. 2,111,193 discloses a method for producing bis (p-aminocumyl) benzenes similar to the above using an activated clay catalyst, but the raw material diisopropylbenzenedicarbinols is m-form. In that case, there is a problem that the target compound bis (p-aminocumyl) benzenes cannot be obtained in high yield.

The inventors of the present invention have conducted extensive studies to solve the problems associated with the above-mentioned conventional techniques, and when producing bis (p-aminocumyl) benzenes from diisopropylbenzenedicarbinols and anilines, If a specific synthetic zeolite is used as a catalyst, the target compound bis (p-aminocumyl) benzenes can be obtained in high yield and high selectivity, and diisopropylbenzene dicarbinols in m-form are preferable. The inventors have found that the target compound, bis (p-aminocumyl) benzene, can be obtained with a higher yield and a higher selectivity than the p-form, and have completed the present invention.

OBJECT OF THE INVENTION The present invention is intended to solve the problems associated with the prior art as described above, and in particular, it is possible to obtain bis (p) from m-isomer diisopropylbenzenedicarbinols and anilines.
An object of the present invention is to provide a method for producing bis (p-aminocumyl) benzenes, which enables high yield and high selectivity of -aminocumyl) benzenes.

SUMMARY OF THE INVENTION In the method for producing bis (p-aminocumyl) benzenes according to the present invention, diisopropylbenzenedicarbinols and anilines are reacted in the presence of a synthetic zeolite catalyst selected from zeolite-X and zeolite-Y. It is characterized by that.

In the present invention, since a synthetic zeolite catalyst is used in the reaction of diisopropylbenzene dicarbinols, particularly m-form diisopropylbenzene dicarbinols and anilines, the target product, bis (p-aminocumyl) benzenes, is used. In comparison with the process using activated clay as a catalyst, which has been used in the conventional method, it can be obtained with dramatically high yield and high selectivity.

DETAILED DESCRIPTION OF THE INVENTION The method for producing bis (p-aminocumyl) benzenes according to the present invention will be specifically described below.

The synthesis reaction of bis (p-aminocumyl) benzenes according to the present invention proceeds as in the following formula [I] when m is used as diisopropylbenzenedicarbinols and aniline is used as anilines. .

Diisopropylbenzene dicarbinol The diisopropylbenzene dicarbinol used as a starting material in the present invention is represented by the following general formula [II].

[In the formula, Y is halogen, amino, substituted amino, or a lower alkyl group, and m is an integer of 0-4. ] In the above diisopropylbenzene dicarbinols, the two The compound positioned at the meta position or the para position is used, and the compound positioned at the meta position is particularly preferably used.

Specific examples of such diisopropylbenzene dicarbinols include α, α′-dihydroxy-1,3-
Diisopropylbenzene, α, α′-dihydroxy-2,
4-dipropyltoluene, α, α′-dihydroxy-3,5
-Dipropyl chlorobenzene or the like is used.

Anilines The anilines used as a starting material in the present invention are represented by the following general formula [III].

[In the formula, R ₁ and R ₂ may be the same or different,
Hydrogen or an alkyl group having 1 to 3 carbon atoms, X is halogen or an alkyl group having 1 to 3 carbon atoms, and n is 0 to 0.
It is an integer of 4. ] Specific examples of such anilines include aniline, N-methylaniline, N, N-dimethylaniline, N
-Ethylaniline, 2-methylaniline, 2,6-xylidine (2,6-dimethylaniline), 3-isopropylaniline and the like are used.

Synthetic Zeolite Catalyst In the present invention, the following specific synthetic zeolite is used as a catalyst when the diisopropylbenzenedicarbinols and the anilines are reacted as described above.

The synthetic zeolite used in the present invention has the general formula M
^An aluminosilicate compound represented by ^{n +} _{x / y} [(AlO ₂ ) × (SiO ₂ ) y] · mH ₂ O, of which zeolite-X and zeolite-Y are used in the present invention. Further, in the present invention, synthetic zeolites obtained by ion-exchange of ^{Mn +} ions of these zeolites with protons, alkaline earth metal ions, rare earth ions or transition metal ions are used. The synthetic zeolite is preferably used after being calcined in air at a temperature of 300 to 600 ° C. before use.

When the above synthetic zeolite is used as a catalyst when reacting diisopropylbenzene dicarbinols with anilines, the target compound bis (p-aminocumyl) benzenes can be obtained in high yield and high selectivity.
In particular, when an m-form in which two isopropyl groups containing a hydroxyl group are substituted at the m-position with respect to the benzene nucleus is used as the diisopropylbenzenedicarbinol as a starting material, the use of the above synthetic zeolite catalyst makes a leap forward. As a result, the yield of 1,3-bis (p-aminocumyl) benzene which is the target compound is increased.

For example, when a 1,3-bis (p-aminocumyl) benzene is produced by reacting an m-form of diisopropylbenzenedicarbinol with aniline, a calcium-exchanged Y-type synthetic zeolite catalyst is used to produce 1,3-bis (p-aminocumyl) benzene. (P
The yield of -aminocumyl) benzenes reaches 95%.
On the other hand, when activated clay that is classified as a solid acid catalyst like the synthetic zeolite and taught in the above-mentioned US Pat. No. 3,267,145 is used as a catalyst, 1,3-bis (p-aminocumyl) benzene is used. The yield of the kind reaches only 45%.

When a calcium-exchanged Y-type zeolite catalyst is used to produce 1,4-bis (p-aminocumyl) benzenes by reacting P-form diisopropylbenzenedicarbinol with aniline, the m-form diisopropylbenzene is used. The target compound cannot be obtained in a higher yield than when benzenedicarbinol is used as a starting material. This suggests that the above synthetic zeolite catalyst functions as a unique catalyst in the reaction according to the present invention.

Reaction Conditions The reaction of diisopropylbenzenedicarbinols and anilines using the above synthetic zeolite catalyst according to the present invention can be carried out under normal pressure or under pressure. When the reaction is carried out under normal pressure, it is preferable to carry out the reaction at a temperature not higher than the boiling point of the starting material, usually about 195 ° C. or lower, while removing water as a reaction product out of the system. When the reaction is carried out under pressure,
By the method of removing the generated water or the method of not removing it,
The reaction can be carried out at temperatures above 195 ° C.

In the present invention, it is preferable to carry out the reaction under pressure at a high reaction temperature of 220 to 260 ° C., because the yield of the desired bis (p-aminocumyl) benzenes is high.

The reaction of the diisopropylbenzene dicarbinols with the anilines according to the present invention is preferably carried out in a state where the anilines are in a large excess.
It is used in an amount of at least mol, more preferably 5 to 20 mol. In addition, a suitable solvent can be used in the reaction, and as such a solvent, various hydrocarbons, decane, dodecane, cumene, benzene, toluene, chlorobenzene and the like can be used.

The reaction can be carried out batchwise or continuously.
When the reaction is carried out in a batch system, the above synthetic zeolite catalyst is preferably used in an amount of 3 to 20 parts by weight per 100 parts by weight of diisopropylbenzenedicarbinols. In the continuous reaction, it is preferable to carry out the reaction so that the residence time is about 10 to 180 minutes.

To separate and purify the target compound, bis (p-aminocumyl) benzenes, from the reaction mixture obtained after the completion of the reaction, a usual separation and purification means is used, and one example thereof is as follows. First, the synthetic zeolite catalyst is removed from the reaction mixture by filtration, and the obtained filtrate is concentrated or cooled as it is to precipitate crude crystals of the target compound. The crude crystals are recrystallized from an appropriate solvent to obtain purified crystals of the target compound.

In the present invention, the used synthetic zeolite catalyst can be reused by washing with acetone, methanol, ethanol or the like under heating.

As described above, bis (p-aminocumyl) benzenes are obtained. Specific examples of the bis (p-aminocumyl) benzenes include 1,3-bis (p-aminocumyl) benzene and 1,4- Bis (p-aminocumyl) benzene, 1,3-bis (p-N-methylaminocumyl) benzene, 1,4-bis (p-N, N'-dimethyl-aminocumyl)
Benzene etc. are indicated.

Effect of the Invention In the present invention, since a synthetic zeolite catalyst selected from zeolite-X and zeolite-Y is used when reacting diisopropylbenzenedicarbinols, particularly m-isomer diisopropylbenzenedicarbinols and aniline, Bis (p-aminocumyl), the desired product
Compared with the process using activated clay as a catalyst in which benzenes have been used in the conventional method, it can be obtained with dramatically high yield and high selectivity.

Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

Example 1 First, a Ca-exchanged Y-type zeolite was prepared from the Y-type synthetic zeolite as follows.

40 g of Y-type zeolite (manufactured by Toyo Soda Co., Ltd.), 150 g of calcium nitrate (tetrahydrate) and 1350 g of water were placed in a 2 l separable flask equipped with a condenser and a stirrer, and reacted at 100 ° C. for 6 hours. Thereafter, the solid content was filtered off by centrifugation. The solid component thus filtered off was placed in the 2 l flask described above, 150 g of calcium nitrate and 1350 g of water were added, the mixture was reacted again at 100 ° C. for 6 hours, and then the filtration was repeated. This operation was repeated once more. Then, the solid content filtered off by centrifugation is repeatedly washed with 1500 ml of water three times at room temperature, and after washing with water, the solid content is dried at 80 ° C. for 3 hours and then calcined at 500 ° C. for 8 hours. A Ca-Y type zeolite was obtained.

The composition of the Ca-Y type zeolite thus prepared is
The Ca exchange rate was 83.4% by weight with Ca5.96% by weight and Na 1.18% by weight.

Next, using the Ca-Y type zeolite obtained as described above as a catalyst, 1,3-bis (p-aminocumyl) benzene was produced as follows.

93 g (1 mol) of aniline, 19.4 g (0.1 mol) of diisopropylbenzenedicarbinol, which is an m-form, and 1.36 g of Ca-Y type zeolite as a catalyst (7 for dicarbinol).
(% By weight) was charged into a 200 ml round-bottomed flask equipped with a stirrer and a condenser, and reacted at 190 ° C. for 3 hours. After the catalyst was filtered from the obtained reaction liquid and the reaction liquid was subjected to gas chromatographic analysis, the yield of 1,3-bis (p-aminocumyl) benzene was 95 mol%. The results are shown in Table 1 for comparison.

Example 2 In Example 1, the amount of Ca-Y type zeolite catalyst used was 1.
1,3-Bis (p-aminocumyl) benzene was prepared in the same manner as in Example 1 except that the amount was changed from 36 g to 0.78 g (4% by weight based on dicarbinol) and the reaction time was changed from 3 hours to 5 hours. Was manufactured. The yield of 1,3-bis (p-aminocumyl) benzene was 84%.

Example 3 A La-exchanged Y-type zeolite catalyst (La exchange rate: 92%) was prepared in the same manner as in Example 1.

Next, 1,3-bis (p-aminocumyl) benzene was produced in the same manner as in Example 1 except that the reaction time was 2 hours using the obtained La-Y type zeolite catalyst. However, the amount of the La-Y type zeolite catalyst used was 3.88 g.

The yield of 1,3-bis (p-aminocumyl) benzene is 85%
Met.

Example 4 A proton exchanged Y-type zeolite (proton exchange rate 93%) was prepared in the same manner as in Example 1.

Next, using the obtained HY type zeolite catalyst, Example 1
1,3-bis (p-aminocumyl) benzene was produced in the same manner as in.

The yield of 1,3-bis (p-aminocumyl) benzene is 88%
Met.

Example 5 In Example 1, N-methylaniline was used as the aniline, the amount used was 107 g (1 mol), and the reaction time was 2
1,3-bis (p-aminocumyl) benzene was produced in the same manner as in Example 1 except that the time was changed.

The yield of 1,3-bis (p-N-methylaminocumyl) benzene was 75%.

Example 6 A Ca-exchanged X-type zeolite (Ca exchange rate: 85%) was prepared in the same manner as in Example 1.

Next, 1,3-bis (p-aminocumyl) benzene was produced in the same manner as in Example 1 using the obtained Ca-Y type zeolite catalyst.

The yield of 1,3-bis (p-aminocumyl) benzene is 84%
Met.

Comparative Example 1 1,3-bis (p-aminocumyl) benzenes were prepared in the same manner as in Example 1 except that activated clay was used as the catalyst, the amount used was 3.88 g, and the reaction time was 2 hours. Was manufactured.

The yield of 1,3-bis (p-aminocumyl) benzene is 45%
Met.

Example 7 1,4-bis (p-aminocumyl) was prepared in the same manner as in Example 1 except that 19.4 g (0.1 mol) of p-isomer diisopropylbenzenedicarbinol was used as the starting material. Benzene was produced.

40% yield of 1,4-bis (p-aminocumyl) benzene
Met.

Comparative Example 2 In Example 1, except that p-form diisopropylbenzenedicarbinol was used as a starting material, and activated clay was 1.55 g as a catalyst and the reaction time was 2 hours.
1,4-bis (p-aminocumyl) as in Example 1
Benzene was produced. 1,4-bis (p-aminocumyl)
The yield of benzene was 78%.

The above results are shown in Table 1.

From Table 1, m-diisopropylbenzenedicarbinols were reacted with anilines to prepare 1,3-bis (p-
When the above synthetic zeolite is used in the production of (aminocumyl) benzene, the yield of 1,3-bis (p-aminocumyl) benzene is dramatically improved as compared with the case of using a solid acid catalyst such as activated clay. I understand that

When the above synthetic zeolite catalyst is used, p
1,4-bis (p-aminocumyl) benzene cannot be obtained in a high yield with the dicarbinols in the body, and 1,3-bis (p-aminocumyl) benzene cannot be obtained in a high yield only when the m-dicarbinol is used as a starting material. It can also be seen that (p-aminocumyl) benzene is obtained.

Claims (3)

[Claims] 1. Bis (p-aminocumyl) benzenes, characterized in that diisopropylbenzene dicarbinols and anilines are reacted in the presence of a synthetic zeolite catalyst selected from zeolite-X and zeolite-Y. Manufacturing method. 2. The method according to claim 1, wherein the diisopropylbenzene dicarbinols are m-forms. 3. The method according to claim 1, wherein the anilines are aniline, N-methylaniline and N, N'-dimethylaniline.