JPH0148A - Method for producing 3,3',4,4'-biphenyltetracarboxylic acid tetraester - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a process for producing 3,3',4,4'-biphenyltetracarboxylic acid tetraester.

[Background of the Invention] 0-phthalic acid diester is produced by supplying molecular oxygen to 0-phthalic acid diester at high temperature in the presence of a catalyst consisting of a palladium salt, a basic bidentate ligand, and a copper salt. It has been known for some time that 3.3°, 4.4'-biphenyltetracarboxylic acid tetraester can be selectively obtained by trimerization. In the above diminution reaction, in addition to the target 3°3',4,4'-biphenyltetracarboxylic acid tetraester (hereinafter referred to as S monolithic), 2°3.3'
, 4°-biphenyltetracarboxylic acid tetraester (
(hereinafter referred to as a) is produced as a by-product. Therefore, in the dimerization reaction described above, improving the selectivity is an issue. Therefore, when carrying out the above dimerization reaction, by sequentially replenishing the reaction solution with the above catalyst components (part or all of the catalyst), it is possible to improve ,3'.

A technique for increasing the production yield of 4.4°-biphenyltetracarboxylic acid tetraester has already been proposed (Japanese Unexamined Patent Publication No. 60-51150).

The above-mentioned method using sequential replenishment of the catalyst component is carried out, for example, by adding the catalyst component directly to the reaction tank in 1 to 10 portions, and the desired product is 3, 3°, 4, 4.
Although it is effective in improving the production yield of °-biphenyltetracarboxylic acid tetraester and is highly useful, in order to increase the usefulness of the above dimerization reaction, it is necessary to further improve the production ratio (selectivity) of S integrally. It is desirable that the

[Objective of the Invention] The main object of the present invention is to produce O-phthalic acid diester in the presence of a catalyst consisting of a palladium salt, a basic divalent ligand, and a copper salt, which are successively replenished in a reaction tank. A method for producing 3,3′,4,4°-biphenyltetracarboxylic acid tetraester (S integral) by carrying out a dimerization reaction of
It is an object of the present invention to provide an improved method in which the selectivity of the above-mentioned S is further improved.

[Summary of the Invention] The present invention is directed to the present invention, in which 0.0
- Dim formation reaction of phthalic acid diester, 3.3°
, 4,4°-biphenyltetracarboxylic acid tetraester, replenishment of the catalyst component is carried out by introducing the catalyst component into the circulation line attached to the reaction tank while circulating the reaction solution. 3.3°, characterized in that it is carried out by introducing a mixture of catalyst components and circulating reaction liquid into the reaction tank through the circulation line.

4. A method for producing 4°-biphenyltetracarboxylic acid tetraester.

[Detailed Description of the Invention] Next, the present invention will be described in detail with reference to the accompanying drawings as necessary.

The method of the present invention can be carried out, for example, using the dimerization reactor schematically shown in the attached FIG. 1.

In the dimerization reactor shown in FIG. 1, a reaction liquid circulation line 3 equipped with a circulation pump 2 is attached to the binomization reaction JIP 11. A catalyst charging device 4 is provided in the middle of the circulation line 3, and is used for replenishing the catalyst component in the present invention. The dimerization reaction J41 is equipped with a stirrer 5, a raw material introduction conduit 6, a product discharge conduit 7, and an air supply conduit 8 as in the conventional dimerization reaction apparatus.

In the method for producing 3,3°,4,4°-biphenyltetracarboxylic acid tetraester of the present invention, first, 0-
Usually 0.00005 to 0.00 to phthalic acid diester.
005 times molar, preferably o,oooot~0.004
A palladium salt of twice the mole, a basic bidentate ligand compound of usually 0.5 to 4 times the mole, preferably 0.6 to 3 times the mole of the palladium salt, and a basic bidentate ligand compound of usually 0.5 to 4 times the mole of the palladium salt. A dimerization reaction using a catalyst consisting of a copper salt of .01 to 5 times the mole, preferably 0.02 to 4 times the mole, together with the 0-phthalic acid diester! Introduced into f11, the introduced catalyst and 0-
While stirring the phthalic acid diester using the stirrer 5, a gas containing molecular oxygen (e.g., air) is supplied from the air supply inlet pipe 8 to about 140 to 260°C, preferably 1
While heating at 60 to 250°C, o-phthalic acid diester is dimerized to selectively form 3.3' and 4.4'.
-Biphenyltetracarboxylic acid tetraester is partially produced.

Note that the above-mentioned initial addition of the catalyst components is carried out at around room temperature (approximately 5
It is preferable to carry out the reaction by adding each catalyst component to the O-phthalic acid diester at a temperature of 50° C. to 50° C., and then heating the packed reaction solution to the reaction temperature. The catalyst components can also be added by first heating the 0-phthalic acid diester and then adding each catalyst component, but in this case, if only the palladium salt is added first, the palladium salt will be Since it may precipitate as metallic palladium, it is appropriate to add the palladium salt at the same time as the basic bidentate ligand compound or after the addition of the basic bidentate ligand compound. Further, when a chelate salt of a palladium salt and a basic bidentate ligand compound is used, it is more suitable because there is no precipitation of metallic palladium as described above.

The above-mentioned 0-phthalic acid diester, each catalyst component, and the gas containing molecular oxygen used in the present invention are described in detail in JP-A-60-51160.

During or after this dimerization reaction, for example,
The amount of the palladium salt used is within the range of 0.001 to 0.01 times the mole, preferably 0.002 to o, oos times the mole, relative to the total amount of the 0-phthalic acid diester used,
Moreover, the total amount of the basic bidentate ligand compound used as a catalyst component is 0.01 to 5 times the mole, preferably 0.6 to 3 times the mole, particularly preferably 0.01 to 5 times the mole, particularly preferably 0.6 to 3 times the mole of the total amount of the palladium salt used. 8
~2 times the mole, and the total amount of the copper salt used as a catalyst component is within the range of 0.01 to 5 times the mole, preferably 0.02 to 4 times the mole of the total amount of the palladium salt used. While maintaining the catalyst concentration in the reaction system so that 3,3°, 4°4°-biphenyltetra Produces carboxylic acid tetraester.

In the method of the present invention, the above-described sequential addition of catalyst components from the second time onwards is carried out through the catalyst charging device 4 while circulating the reaction liquid through the reaction liquid circulation line 3 attached to the dimerization reaction tank 1 shown in FIG. This is done by adding more catalyst components. The circulation line is a conduit through which a part of the reaction liquid is extracted from the reaction tank 1 by the circulation pump 2 and returned to the reaction tank 1 again.

The activation of the circulation line 3, ie the circulation of the reaction liquid through the circulation line 3, is preferably carried out only when the catalyst component or catalyst is introduced. If the reaction solution is constantly circulated, the circulation pump may unnecessarily draw in air. The circulation flow rate of the reaction solution is usually 1 to 10 m/sec, and preferably 2 to 4 m/sec.

In the present invention, the catalyst component added after the second time of sequential addition may be a mixture of each catalyst component, or a chelate compound obtained from a palladium salt and a basic bidentate ligand compound. There may be. Further, the catalyst component may be used in the form of a powder or suspended in a solvent such as O-phthalic acid diester, but it is preferable to use the catalyst component in the form of a powder.

In the present invention, the amount of catalyst components added after the second sequential addition is not particularly limited as long as the catalyst concentration of the entire reaction system can be maintained within the above range.
Generally, the amount of each catalyst component added sequentially is 0.05 to 3 times the amount of each catalyst component used initially, especially 0.05 to 3 times the amount of each catalyst component used initially. It is preferably about 1 to 2 times the mole.

3°3',4 selectively produced by the method of the present invention
．． 4''-biphenyltetracarboxylic acid tetraester can be easily separated and produced from the reaction solution by a conventionally known method, such as distillation or crystallization.

3.3°,4,4°-biphenyltetracarboxylic acid tetraester is hydrolyzed by a conventionally known method 1, for example, a method of hydrolysis at high temperature and high pressure, or a method of hydrolysis by adding an acid or alkali. 3.3',4,4'-biphenyltetracarboxylic acid;
．． 3°, 4° 4°-Biphenyltetracarboxylic acid is anhydrified by heating to high temperature to produce 3.3°, 4.4'
- biphenyltetracarboxylic dianhydride can be obtained. 3.3',4,4'-biphenyltetracarboxylic dianhydride is a compound useful as one of the raw material monomers for aromatic polyimide.

[Effects of the Invention] According to the present invention, by carrying out the method for producing 3,3°,4,4°-biphenyltetracarboxylic acid tetraester (S integral) by dielectrification of O-phthalic acid diester, the conventional method can be improved. It becomes possible to obtain 3,3°, 4.4°-biphenyltetracarboxylic acid tetraester with higher selectivity than in the above method.

The high selectivity achieved by the present invention is believed to be due to the following reasons.

According to the present invention, the catalyst components that are added sequentially are instantly introduced into the reaction tank as a mixture with the reaction liquid circulating at high speed, so deactivation of the catalyst components during the charging operation is reduced, and further added catalyst components is uniformly dispersed in the reaction solution in the reaction tank within a short time, resulting in improved uniformity of the reaction. Furthermore, when the catalyst components are added, part of the reaction liquid under stirring is circulated through the circulation line, so the reaction liquid in the reaction tank is stirred in a complicated manner and is stirred in a turbulent state. It is believed that the catalyst component introduced through the line is not localized in the reaction liquid in the reaction tank and is easily and uniformly dispersed, promoting the smooth progress of the desired reaction.

In the above dimerization reaction of O-phthalic acid diester, in addition to the target 3,3°, 4,4'-biphenyltetracarboxylic acid tetraester, 2,3,
3°, 4′-biphenyltetracarboxylic acid tetraesters and high-boiling compounds are produced, but according to the method of the present invention, 3,3°, 4,4°-biphenyltetracarboxylic acid tetraesters are produced relative to the total trimerization product. The ester selectivity is usually about 70 mol % or higher, and can be increased to 80 to 90 mol % by selecting reaction conditions.

Next, Examples and Comparative Examples of the present invention will be shown.

[Example 1] In a reaction tank equipped with a circulation line as shown in Fig. 1,
Dimethyl 0-phthalate (hereinafter abbreviated as DMP) 21
00Il (2500kg), palladium acetate 945g,
Copper acetate hydrate 250g, 〇-phenanthroline 755g
was added at room temperature (25°C), and then heated to 230°C, and while bubbling air from the bottom of the reaction solution at 1100 N'/hour, DMP was dimerized for 2 hours.

Next, the circulation line is activated, the reaction solution is passed through the circulation line at a flow rate of 2 m/sec, and palladium acetate 94 is added to the circulation stream.
5 g of copper acetate hydrate, and 755 g of 0-phenanthroline were mixed and added as powder. After stopping the circulation line, the dimerization reaction was roughly continued for 2 hours (4 hours from the start of the reaction) under the same conditions as above, and the same catalyst addition operation as above was repeated 4 hours and 6 hours later. The dimerization reaction was continued under the same conditions as above until 10 hours later.

Table 1 shows the conversion rate and reaction yield of each compound for the reaction solution after 10 hours.

[Example 2] The same procedure as in Example 1 was performed except that the second and subsequent catalyst addition operations were performed in a state in which each catalyst component was suspended in DMP.

Table 1 shows the conversion rate and reaction yield of each compound for the reaction solution after 10 hours.

[Comparative example! ] ' The second and subsequent catalyst addition operations were carried out in the same manner as in Example 1, except that the catalyst was not added to the circulation line but was directly added to the reaction tank while the circulation line was stopped. Ta.

Table 1 shows the conversion rate and reaction yield of each compound for the reaction solution after 10 hours.

Margin below

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an example of a secondary chemical reaction apparatus used for carrying out the production method of the present invention. 1: Reaction tree 2: Circulation pump 3: Circulation line 4: Catalyst injection [1 5: Stirrer 6: Raw material introduction conduit 7: Product discharge conduit 8: Air supply conduit Patent applicant Ube Industries, Ltd. Agent: Patent Attorney Hatao Yanagawa

Claims (1)

[Claims] 1. In the reaction tank, a dimerization reaction of o-phthalic acid diester is carried out in the presence of a catalyst consisting of a palladium salt, a basic bidentate ligand, and a copper salt, which is successively replenished.
When producing 4'-biphenyltetracarboxylic acid tetraester, the catalyst component is replenished by supplying the catalyst component into the circulation line while circulating the reaction liquid through the circulation line attached to the reaction tank. A method for producing 3,3',4,4'-biphenyltetracarboxylic acid tetraester, which is carried out by introducing a mixture of and a circulating reaction liquid into a reaction tank through the circulation line. 2. The flow rate of the reaction solution flowing through the circulation line is 1 to 10 m/
2. The method for producing 3,3',4,4'-biphenyltetracarboxylic acid tetraester according to claim 1, characterized in that the 3,3',4,4'-biphenyltetracarboxylic acid tetraester is produced in seconds. 3. 3,3',4,4'-biphenyltetracarboxylic acid according to claim 1, characterized in that the palladium salt is introduced in the form of powder together with the basic bidentate ligand and the copper salt into the circulation line. Method for producing acid tetraester.