JPH0329779B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel meta-terphenyltetracarboxylic acid or its dianhydride and a method for producing the same.

[Conventional technology]

Conventionally, aromatic tetracarboxylic acids or dianhydrides thereof include pyromellitic acid or dianhydrides,
Benzophenonetetracarboxylic acid or its dianhydride is known, and is mainly known as a raw material for polyimide resin.

In addition, as terphenyltetracarboxylic acid, West German Patent Publication No. 2100391, British Patent No.
Para-terphenyl-2,3,2″,3″-tetracarboxylic acid represented by the formula [] described in specification No. 1338932 and US Patent No. 3891633
2,3: 2″,3″-dianhydride is known.

The tetracarboxylic dianhydride represented by the formula [] is a compound synthesized by the route shown by the following reaction formula [].

That is, an intermediate compound is obtained by a Diers-Alder reaction between 1,4-bis(α-furano)benzene and two molecules of maleic anhydride, and this is further dehydrated with concentrated sulfuric acid or polyphosphoric acid to form a tetracarboxylic acid. Due to the nature of the reaction, the positions of the acid anhydride groups are the 2,3-position and the 2″,3″-position.
It is the rank.

The compound represented by the formula [] is used as a crosslinking agent for epoxy resins or phenol formaldehyde resins.

Furthermore, meta-terphenyltetracarboxylic acid has only been reported in French Patent No. 1556159 (Chemical Abstracts Vol. 71, 49609k), and its synthesis method is based on the following reaction formula []. will be shown.

That is, using copper as a catalyst, meta-benzenedisulfonyl chloride and excess phthalic anhydride are reacted under phthalic anhydride reflux conditions while generating sulfur dioxide gas and hydrogen chloride gas to form meta-terphenyltetracarboxylic acid. It is made into a dianhydride, and the melting point of the obtained compound is 130~
It was 165℃.

[Problem that the invention seeks to solve]

Polyimide resins obtained from conventionally known aromatic tetracarboxylic dianhydrides and diamine compounds, such as diaminodiphenyl ether and diaminodiphenylmethane, are known as heat-resistant resins, but recent technology With the advancement of technology, further improvement in heat resistance is desired.

Further, para-terphenyltetracarboxylic dianhydride represented by the above formula [] is known as a crosslinking agent for epoxy resins or phenolic resins.
However, since the para-terphenyltetracarboxylic dianhydride has acid anhydride groups at the 2,3-position and the 2'',3''-position, the polyimide resin synthesized using it as a raw material has a high It is difficult to quantify the molecular weight and therefore has insufficient heat resistance.

Furthermore, in the meta-terphenyltetracarboxylic dianhydride, the position of the acid anhydride group is unknown due to the nature of its synthesis reaction, and the melting point of the resulting compound is wide, ranging from 130 to 165°C. , is a mixture of various compounds with different positions of acid anhydride groups,
When such a tetracarboxylic dianhydride is used as a raw material for a polyimide resin, only a low molecular weight polyimide resin is obtained, and the heat resistance is insufficient.

In order to solve these problems, the present invention provides novel terphenyltetracarboxylic acids or dianhydrides thereof and methods for producing them.

[Means for solving problems]

The first invention is meta-terphenyl-3,4,
It relates to 3″,4″-tetracarboxylic acid or its dianhydride.

Meta-terphenyl-3,4,3'',4''-tetracarboxylic acid is a compound represented by the following formula [].

In addition, this dianhydride meta-terphenyl-3,4,3″,4″-tetracarboxylic acid-3,4:
3″,4″-dianhydride is a compound represented by the following formula [].

The meta-terphenyltetracarboxylic acid or its dianhydride according to the present invention has carboxyl groups or acid anhydride groups located at both ends of the meta-terphenyl at the 3, 4-position and the 3'', 4''-position. Because there is
When polyamic acid is reacted with a diamine compound and further dehydrated to form a polyimide resin, it becomes a linear structure with extended molecular chains, making it possible to provide a polyimide resin with a large molecular weight and excellent heat resistance.

Furthermore, the meta-terphenyltetracarboxylic acid or dianhydride thereof according to the present invention is a single compound, as is clear from the following examples.

The second invention relates to a method for producing the compound according to the first invention.

That is, the second invention is meta-terphenyl-3,4,4, which is characterized by oxidizing 3,4,3'',4''-tetramethyl-meta-taphenyl or further subjecting it to a dehydration ring closure reaction. This invention relates to a method for producing 3″,4″-tetracarboxylic acid or its dianhydride.

The above 3,4,3'',4''-tetramethyl-meta-terphenyl can be obtained by subjecting a Grignard reagent of 4-halogeno-ortho-xylene and meta-dihalogenobenzene to a double cross-coupling reaction.

The manufacturing method will be explained in detail below.

The meta-terphenyltetracarboxylic acid and dianhydride thereof according to the present invention can be produced by the reaction represented by the following formula [].

(Here, _{X.sub.1 and} By adding halogenobenzene and a nickel metal complex catalyst, 3,4,
3″,4″-tetramethyl-meta-terphenyl. The resulting intermediate, 3,4,3″,4″-tetramethyl-meta-terphenyl, was meth-terphenyl treated with permanganate, nitric acid, or by liquid phase air oxidation.
terphenyl 3,4,3″,4″-tetracarboxylic acid, and then heated or with acetic anhydride to give meta-terphenyl 3,4,3″,4″-tetracarboxylic acid-3,4:3″, 4″-Dianhydride. Also,
The dianhydride can be obtained directly by gas phase oxidation of 3,4,3'',4''-tetramethyl-meta-terphenyl.

This method will be explained in more detail.

As 4-halogeno-ortho-xylene, 4
-iodo-ortho-xylene, 4-bromo-ortho-xylene, etc.

The method of using 4-halogeno-ortho-xylene as a Grignard reagent is to use 1.0 gram atom or more of metallic magnesium per 1.0 mole of 4-halogeno-ortho-xylene. When the amount of magnesium metal is less than 1.0 gram atom, unreacted 4-halogeno-ortho-xylene remains and is combined with the Grignard reagent of 4-halogeno-ortho-xylene and 4-halogeno-ortho-xylene during the next coupling reaction.
This is not preferred because halogeno-ortho-xylene reacts to produce tetramethyl-biphenyl. The reaction temperature for Grignard reagent is 0℃
The above reaction is carried out at a temperature below the reflux temperature of the solvent, and the reaction time is 1 to 10 hours.

When the amount of metallic magnesium used in the reaction exceeds 1.0 gram atom per 1.0 mole of 4-halogeno-ortho-xylene, unreacted metallic magnesium remains, which is removed by filtration. Solvents used at this time include ethyl ether and tetrahydrofuran.

Examples of meta-dihalogenobenzene include meta-dibromobenzene and meta-dichlorobenzene. Among these, when meta-dichlorobenzene is used, the yield of the double cross-coupling reaction becomes higher. The amount of meta-dihalogenobenzene used is 0.5 mol per 1.0 mol of Grignard reagent of 4-halogeno-ortho-xylene. When the amount is less than 0.5 mol, the Grignard reagent remains after the reaction is completed, and this is hydrolyzed during the next washing with water to form ortho-xylene, which does not interfere with the reaction, but the yield decreases. Moreover, if it exceeds 0.5 mol, the by-product of poly-para-phenylene increases, which is not preferable.

Examples of the nickel metal complex catalyst include dichlorobis(triphenylphosphine)nickel, dibromobis(triphenylphosphine)nickel, diiodobis(triphenylphosphine)nickel,
Dichloro[1,2-bis(diphenylphosphino)ethane]nickel, dibromo[1,2-bis(diphenylphosphino)ethane]nickel, dichloro[1,3-bis(diphenylphosphino)]
Propane]nickel, dibromo[1,3-bis(diphenylphosphino)propane]nickel, and the like.

The nickel metal complex catalyst is preferably used in an amount of 0.1 to 1.0% by weight based on the equivalent amount of 4-halogeno-ortho-xylene component of the Grignard reagent.

The double cross coupling reaction is preferably carried out at 20 to 60°C, and the reaction time is usually 1 to 5 hours. If the reaction temperature is low, the reaction time will only become longer and this is not an essential problem, but if the reaction temperature is higher than 60°C, high-boiling components such as polyphenylene or by-products such as tetramethyl-biphenyl will be produced. tends to increase.

After the reaction is completed, the magnesium salt is removed by washing with water. The intermediate 3,4,3'',4''-tetramethyl-meta-terphenyl can be purified by washing with ethanol or the like, if necessary.

Intermediate 3,4,3″,4″-tetramethyl-meta-
The meta-terphenyl 3,4,3'',4''-tetracarboxylic acid according to the invention can be obtained by oxidizing terphenyl.

The case of oxidation using permanganate will be explained next.

As the permanganate, potassium permanganate or the like is used. The solvent used is a mixture of water and pyridine, preferably in a weight ratio of 1.0 of water to 0.5 to 2.0 of pyridine. This solution 100
Add 5 to 15 g of 3,4,3'',4''-tetramethyl-meta-terphenyl per g, and gradually add 12 times the molar amount of potassium permanganate. If the amount is less than 12 times the mole, the oxidation reaction will not be completed. Reaction temperature is 50℃
Perform the above below the reflux temperature (93℃),
The reaction time is usually 5 to 10 hours. In this reaction, potassium permanganate becomes manganese oxide, which is insoluble in the solvent, and this is removed by filtration. Since meta-terphenyl-3,4,3'',4''-tetracarboxylic acid is dissolved in the filtrate as a potassium salt, acid precipitation treatment is performed with concentrated hydrochloric acid, but since the filtrate contains pyridine, After pyridine is distilled off using a rotary evaporator, it is precipitated with acid. Concentrated hydrochloric acid is added until the pH of the solution reaches 1 to obtain white crystals of meta-terphenyl-3,4,3'',4''-tetracarboxylic acid. At this time, since it is precipitated from an aqueous solution, meta-terphenyl-3,4,3'',4''-tetracarboxylic acid is a compound having two molecules of water of crystallization.

The meta-terphenyl thus obtained
3,4,3″,4″-tetracarboxylic acid, 120-250
℃ under reduced pressure of 5 to 50 mmHg for 1 to 24 hours, the above meta-terphenyl-3,4,3'',
Meta-terphenyl-3,4,3'',4 is obtained by adding 30 to 60 g of acetic anhydride to 1 g of 4''-tetracarboxylic acid, heating under reflux for 0.5 to 2 hours, followed by hot filtration and recrystallization. ″-tetracarboxylic acid-3,
4:3″,4″-dianhydride.

Meta-terphenyl-3,4, according to the present invention
3″,4″-tetracarboxylic acid or its dianhydride is
It is useful as a raw material for polyimide resins and other resins, and as a curing agent for epoxy resins, phenolic resins, etc.

〔Example〕

Hereinafter, % means weight %.

Example 1 (1) Production of Grignard reagent A two-four-necked flask equipped with an Aline condenser, a dropping funnel, a thermometer, and a stirring device was thoroughly dried under an argon gas atmosphere, and then 100 ml of tetrahydrofuran, which had been dehydrated with metallic sodium, was added.
Magnesium metal 9.72g and bromo-ortho-
Xylene (manufactured by Aldrich, 4-bromo-ortho-xylene 75% and 3-bromo-ortho-
10.0 g of xylene 25% mixture) was added. When the reaction solution started to become cloudy and Grignard reagent started to be produced, a mixture of 64.0 g of bromo-ortho-xylene and 100 ml of tetrahydrofuran, which was the same as above, was added dropwise from the dropping funnel over 1 hour. During this time, since the reaction was exothermic, the reaction temperature was maintained at 40°C while cooling with an ice bath. Since metallic magnesium remained even after the dropwise addition was completed, the mixture was heated in an oil bath and stirred for 5 hours at a temperature of 40°C to completely react the metallic magnesium to form a Grignard reagent.

(2) Production of 3,4,3″,4″-tetramethyl-meta-terphenyl Next, add 0.37 g of dichloro[1,2-bis(diphenylphosphino)ethane]nickel catalyst (bromo-orthoxylene) to the flask. 0.5%)
Add 29.4 g (0.200 mol) of meta-dichlorobenzene from the dropping funnel to tetrahydrofuran.
A solution dissolved in 85 ml was added dropwise over 1 hour. During this time, the reaction temperature was maintained at 35°C. After the dropwise addition was completed, stirring was continued while maintaining the temperature at 35°C for an additional hour to complete the double cross coupling reaction.

300 ml of toluene was added to the reaction-completed solution, and while stirring, 150 ml of ion-exchanged water was gradually added over 1 hour. After removing the lower aqueous layer using a separating funnel, the upper toluene layer was dry-uped using a rotary evaporator. After cooling, the precipitated crystals were taken out, washed three times with ethanol, and then dried under reduced pressure to obtain 24.4 g of colorless plate-shaped crystals.

The melting point of this crystal is 72-73°C, and Figure 1 shows the proton nuclear magnetic resonance ( ^1H -NMR) spectrum and Figure 2 shows the carbon nuclear magnetic resonance ( ^13C -NMR) spectrum.
NMR) spectrum analysis results are shown. In Figure 1, the integrated intensity ratio of absorption based on methyl group protons at 2.29 ppm and 2.32 ppm and absorption based on benzene ring protons at 7.17 to 7.76 ppm is 180:150 (=12:10). , which is in good agreement with the theoretical value. In Figure 2, only 12 peaks appear, indicating that the obtained compound (theoretical carbon number 22) has a symmetrical structure with respect to the benzene ring at the center of terphenyl.
Moreover, the expression [] Absorptions 1 to 10 appear in FIG. 2, in good agreement with the predicted value of the chemical shift of the benzene ring carbon according to the Savitzky rule of the benzene ring carbon with carbon number ~ of the compound represented by .

From the above, it was confirmed that the above crystal was 3,4,3'',4''-tetramethyl-meta-terphenyl.

(3) Production of meta-terphenyl-3,4,3″,4″-tetracarboxylic acid Next, 14.3 g (50 mmol) of 3,4,3″,4″-tetramethyl-meta-terphenyl, 200 g of pyridine, and Pour 200 g of ion-exchanged water into a 14-necked flask equipped with an Aline condenser, thermometer, and stirrer, heat the flask to 80°C, and gradually add 110.7 g (700 mmol) of potassium permanganate over 3 hours. After that, the temperature was maintained at 80° C. and stirring was continued for an additional 5 hours. The precipitate of manganese oxide produced in the reaction was removed by filtration, and the pyridine in the filtrate was distilled off using a rotary evaporator. After acid precipitation with 36% hydrochloric acid, fine white crystals were precipitated. The pH of the solution at this time was 1. After repeating filtration and washing with water twice, it was dried under reduced pressure to obtain 8.9 g of white powdery crystals.

The melting point of this crystal was 296-298°C. The infrared absorption spectrum of this crystal is shown in FIG.
For 0.4 g of this crystal, 50 ml of methanol and 97
% sulfuric acid was added and refluxed for 8 hours to methyl esterify the above crystals. The results of the ¹ H-NMR spectrum of the obtained methyl ester compound are shown in FIG. In Figure 4,
The integrated intensity ratio of the absorption based on methyl group protons at 3.91ppm and 3.94ppm and the absorption based on benzene ring protons at 7.55 to 7.95ppm is as follows:
The value was 175:147 (=12:10.08), which was in good agreement with the theoretical value (methyl ester of the compound of formula []).

Further, the results of elemental analysis of the above crystal were as follows.

Actual value Carbon: 59.65%, Hydrogen: 4.16% Theoretical value Carbon: 65.03%, Hydrogen: 3.47% (However, the theoretical value is the value obtained as a compound of formula []) As a result of elemental analysis, the actual value and the theoretical value are When the above crystal was analyzed using a differential thermal balance at a heating rate of 5°C/min, it was found that the crystals were 211°C and 298°C.
There was an endothermic peak. A weight loss of 17% by weight was observed at 211°C. The endothermic peak at 298°C is due to the melting point, but the endothermic peak at 211°C is due to dehydration. If meta-terphenyl-3,4,3″,4″-tetracarboxylic acid simply undergoes dehydration ring closure and becomes the corresponding acid anhydride due to heating during differential calorimetry analysis, the weight loss would be 9. %. Therefore, the obtained crystal is considered to contain water of crystallization, and the actual value of the above elemental analysis is the theoretical value of elemental analysis when two molecules of water of crystallization are hydrated in the compound of formula [] carbon 59.73
%, in very good agreement with hydrogen 4.10%.

From the above, it was confirmed that the above crystal was meta-terphenyl-3,4,3'',4''-tetracarboxylic acid represented by the formula [] and had two molecules of water of crystallization.

(4) Production of meta-terphenyl-3,4,3″,4″-tetracarboxylic acid-3,4:3″,4″-dianhydride Next, 8.00 g of the above crystals were placed in a 100 ml flask and vacuum Set the inside of the container to 20mmHg with a pump,
It was immersed in an oil bath at 180°C for 15 hours to perform dehydration and ring closure. In this way, 7.29 g of light and colored powdery crystals were obtained. The infrared absorption spectrum and ¹ H-NMR spectrum of this powdered crystal were measured at the fifth
As shown in FIG.

The melting point of this crystal is 296-298℃, and elemental analysis shows that it is 71.17% carbon and 2.79% hydrogen.
Theoretical value (compound of formula []) carbon 71.36%,
Good agreement with 2.72% hydrogen, meta-terphenyl-3,4,3″,4″-tetracarboxylic acid-3,
4:3″,4″-dianhydride was confirmed.

Application example Meta-terphenyl-3 obtained in Example 1,
4,3″,4″-tetracarboxylic acid-3,4:3″,
10.0 g (27.0 mmol) of 4″-dianhydride, 5.41 g (27.0 mmol) of 4,4′-diaminodiphenyl ether and N-methylpyrrolidone as reaction solvent.
87.3g was placed in a 200ml three-necked flask equipped with a stirring device, and stirred for 8 hours at a temperature of 25°C under a nitrogen atmosphere.
weight%). During the reaction, the maximum viscosity of the polyamic acid varnish was 3 poise (measured at 25°C).

The obtained polyamic acid varnish was cast onto a glass plate and heated at 150°C for 1 hour and at 350°C for 1 hour in a hot air constant temperature bath.
Heat treatment was carried out for several hours to remove the reaction solvent, and the polyamic acid was converted into polyimide by a dehydration reaction to obtain a polyimide film with a thickness of 40 μm.

After this polyimide film was left in air at 460°C for 30 minutes, the weight loss was 3.2% by weight, and the weight loss starting temperature was 464°C as determined by thermobalance analysis (heating rate: 10°C/min).

Comparative application example Pyromellitic dianhydride 8.0 g (36.7 mmol), 4,4'-diaminodiphenyl ether 7.34
g (36.7 mmol) and N-methylpyrrolidone
86.9g was reacted in the same manner as in the application example to synthesize a polyamic acid varnish with a nonvolatile content of 15% by weight. At this time,
The maximum viscosity of polyamic acid varnish during the reaction is 3000
It was poise (measured at 25℃).

A polyimide film was obtained from the obtained polyamic acid varnish in the same manner as in the application example, and the heat resistance of this film was measured.The weight loss after being left in air at 460°C for 30 minutes was 3.5% by weight, and thermobalance analysis (elevating The temperature at which the weight loss started at a temperature rate of 10°C/min was 460°C.

〔Effect of the invention〕

Meta-terphenyl-3,4, according to the present invention
3″,4″-tetracarboxylic acid or its dianhydride is
It is a new compound and is useful as a raw material for polyimide resins, etc.

[Brief explanation of drawings]

Figure 1 shows intermediates 3 and 3 in Example 1.
¹ H-NMR spectrum of 4,3″,4″-tetramethyl-meta-terphenyl, Figure 2 shows 3,4,3″,
^13C- of 4″-tetramethyl-meta-terphenyl
NMR spectrum, Figure 3 is the infrared absorption spectrum of meta-terphenyl-3,4,3'',4''-tetracarboxylic acid, Figure 4 is the infrared absorption spectrum of meta-terphenyl-3,4''-tetracarboxylic acid.
¹ H-NMR spectrum of 4,3″,4″-tetracarboxylic acid tetramethyl ester, Figure 5 shows meta-
The infrared absorption spectrum of terphenyl-3,4,3″,4″-tetracarboxylic acid-3,4:3″,4″-dianhydride and Figure 6 show meta-terphenyl-3,4″-tetracarboxylic acid-3,4:3″,4″-dianhydride.
4,3″,4″-tetracarboxylic acid-3,4,3″,
¹ H-NMR spectrum of 4″-dianhydride is shown.

Claims (1)

[Claims] 1. Meta-terphenyl-3,4,3'',4''-tetracarboxylic acid or its dianhydride. 2 Meta-terphenyl-3,4,3″,4″-tetra, which is characterized by oxidizing 3,4,3″,4″-tetramethyl-meta-terphenyl or further subjecting it to a dehydration ring-closing reaction. A method for producing carboxylic acid or its dianhydride. 3 3,4,3″,4″-tetramethyl-meta-terphenyl is obtained by double cross-coupling reaction of a Grignard reagent of 4-halogeno-ortho-xylene and meta-dihalogenobenzene. A method for producing meta-terphenyl-3,4,3'',4''-tetracarboxylic acid or its dianhydride according to Scope 2. 4. The method for producing meta-terphenyl-3,4,3'',4''-tetracarboxylic acid or its dianhydride according to claim 3, wherein the meta-dihalogenobenzene is meta-dichlorobenzene.