JP2951746B2 - Method for producing 1,3-bis (3-aminobenzoyl) benzene - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing 1,3-bis (3-aminobenzoyl) benzene. This 1,3-bis (3-aminobenzoyl) benzene (hereinafter abbreviated as ABB) is used as a raw material for polyimide, polyamide, polyamideimide, bismaleimide and epoxy resin, and is used for curing other maleimide compounds and epoxy compounds. It can also be used as an agent.

[0002]

2. Description of the Related Art The ABB has been discovered by the present inventors and relates to a method for producing the ABB.
A method for reductive dechlorination using nitro-4-chlorobenzoyl) benzene as a raw material was previously filed.

[0003]

However, in the above-mentioned production method, the reduction conditions for performing the dechlorination reaction are strong, so that the carbonyl group is partially reduced.
Since a base is used, an azoxy compound or the like is produced as a by-product, so that a reduction in yield and a complicated purification operation are required, which not only increases the cost but also makes it unnecessary to pollute waste. Therefore, when ABB is manufactured by the above-mentioned method, there is a disadvantage that it is expensive. An object of the present invention is to provide a high-yield and inexpensive production method for industrially producing useful ABB.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, the present invention provides a method of treating a crude 1,3-bis (3-nitrobenzoyl) benzene containing an isomer compound obtained by nitrating 1,3-dibenzoylbenzene with an alcohol in the presence of a basic compound. And reacting substantially only isomers having a nitro group at the o-position and / or p-position to convert to the corresponding alkoxy compound,
In this method, 1,3-bis (3-nitrobenzoyl) benzene is obtained by separating and removing the alkoxy compound, and then reduced to produce 1,3-bis (3-aminobenzoyl) benzene. The present invention comprises a step of purifying 1,3-bis (3-nitrobenzoyl) benzene from a crude product obtained by nitrating 1,3-dibenzoylbenzene, and a step of reducing the step to purify 1,3-bis ( 3-aminobenzoyl) benzene (ABB).

The step of purifying 1,3-bis (3-nitrobenzoyl) benzene of the present invention will be described. The raw material 1,3-bis (3-nitrobenzoyl) benzene is
Usually, the most typical method involves the Friedel-Crafts reaction of isophthaloyl chloride and benzene,
1,3-Dibenzoylbenzene is obtained and produced by nitration. The 1,3-dinitrobenzoylbenzene obtained by this method varies depending on the conditions of the nitration reaction, but is usually 1,3-bis (3-nitrobenzoyl).
It contains about 60 to 85% of benzene, and 1-
(2-nitrobenzoyl) -3- (3-nitrobenzoyl) benzene, 1- (3-nitrobenzoyl) -3-
15 to 4 isomers of (4-nitrobenzoyl) benzene
It contains about 0%. Conventionally, there have been various difficulties in efficiently obtaining desired 1,3-bis (3-nitrobenzoyl) benzene from such a mixture. For example, in order to isolate 1,3-bis (3-nitrobenzoyl) benzene by recrystallization purification, a large amount of a solvent must be used, and recrystallization must be repeatedly performed. The yield of (3-nitrobenzoyl) benzene was greatly reduced, and complicated steps and costs were required for recovery of the solvent used for purification and treatment of the residue. In the method of the present invention, a mixture containing such isomers is treated with an alcohol in the presence of a basic compound, and substantially o o
By converting the nitro group at only the-and p-positions to the corresponding alkoxy group, it is possible to easily separate and remove these isomer compounds, and to obtain high-purity 1,3-bis (3-nitrobenzoyl). ) Benzene can be obtained.

The types of alcohol used in the method of the present invention include lower aliphatic monohydric alcohols such as methanol, ethanol and propanol, alicyclic alcohols such as cyclohexanol, aromatic alcohols such as benzyl alcohol, and ethylene. Although a lower polyhydric alcohol such as glycol can be used, a lower aliphatic monohydric alcohol is preferable, and more preferably an aliphatic monohydric alcohol having 5 or less carbon atoms, in consideration of an alkoxylation reaction rate and costs such as alcohol recovery. Is good. The amount of alcohol used
The content of isomers other than 1,3-bis (3-nitrobenzoyl) benzene contained in the crude 1,3-bis (3-nitrobenzoyl) benzene is not particularly limited as long as it is at least equimolar with the content of isomers. Use an amount that can be stirred together. That is, it is sufficient that the amount is 1 to 5 times the weight of the raw material crude 1,3-bis (3-nitrobenzoyl) benzene.
In particular, when an alcohol is used in a small amount of 1% by weight or less, the reaction may be performed by adding another inert solvent to the raw material and the alcohol. This solvent includes benzene,
Aromatic hydrocarbons such as toluene and monochlorobenzene,
Halogenated hydrocarbons such as 1,2-dichloroethane and 1,1,2-trichloroethane, ethers such as dioxane, diglyme and tetrahydrofuran, ketones such as acetone and methyl ethyl ketone, N, N-dimethylformamide, N-methylpyrrolidone , 1,3-dimethyl-
Aprotic polar solvents such as 2-imidazolidinone and sulfolane; and water.

The basic compound used in the present invention includes:
Hydroxides, carbonates, bicarbonates, sulfites or bisulfites of alkali metals or alkaline earth metals such as potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, calcium hydroxide, sodium sulfite or potassium bisulfite Salts. In addition, there is no inconvenience to use a compound prepared in advance as an alcoholate such as sodium methoxide, sodium ethoxide and potassium butoxide. Rather, when the reaction rate of a lower alcohol solvent is low due to the boiling point, a method of raising the reaction temperature by using an alcoholate of another higher boiling solvent and a lower alcohol is also adopted. The amount of these basic compounds used is determined by the stoichiometric amount of the isomer content other than 1,3-bis (3-nitrobenzoyl) benzene contained in the raw material 1,3-bis (3-nitrobenzoyl) benzene. Or more, and preferably 1.5 to 5 equivalents is sufficient.

The reaction temperature is selected so as to give an appropriate reaction rate in the reaction system, and the reaction is usually carried out at the boiling point of the alcohol used. Raise the temperature to speed up the reaction,
It can also be carried out under pressure. Specifically, 60-1
A range of 20 ° C. is selected. The progress of the reaction can be confirmed by thin-layer chromatography or high-performance liquid chromatography. In the method of the present invention, as a catalyst for accelerating the reaction, a quaternary ammonium salt, a quaternary phosphonium salt, a macrocyclic polyether such as a crown ether,
A phase transfer catalyst such as a nitrogen-containing macrocyclic polyether such as cryptate, a nitrogen-containing chain polyether, polyethylene glycol and its alkyl ether may be added.

In the method of the present invention, 1,3-bis (3-
A common practice for the purification of nitrobenzoyl) benzene is to use crude 1,3-bis (3-nitrobenzoyl) benzene and a predetermined amount of a base, alcohol, and optionally a catalyst or other solvent, and use The reaction is carried out at a temperature equal to or higher than the boiling point of the alcohol obtained, and after the reaction is completed, cooling is carried out, and the precipitated 1,3-bis (3-nitrobenzoyl) benzene is filtered off.

Next, the step of reducing 1,3-bis (3-nitrobenzoyl) benzene of the present invention will be described. 1,
Regarding a method of obtaining 3-A (3-nitrobenzoyl) benzene by reducing 3-bis (3-nitrobenzoyl) benzene, an ordinary method of reducing a nitro group to an amino group (for example, “Experimental Chemistry Course,
15, vol. 15, oxidation and reduction [II], Maruzen (1977) "). More specifically, Veshan reduction using iron powder and hydrochloric acid, reduction using sulfides such as sodium sulfide and sodium hydrosulfide, and catalytic reduction using a Raney catalyst or a relatively low-activity noble metal catalyst can be mentioned. In the case of catalytic reduction, a metal catalyst generally used for catalytic reduction, for example, nickel, palladium, platinum, rhodium, ruthenium, cobalt, copper and the like can be used as the reduction catalyst used.

The solvent used in these reduction reactions is not particularly limited as long as it is inert to the reaction. For example, alcohols such as methanol, ethanol and isopropyl alcohol, ethylene glycol and propylene glycol Glycols such as ether, dioxane, tetrahydrofuran, 2-methoxyethanol, ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, aliphatic hydrocarbons such as hexane and cyclohexane, aromatic hydrocarbons such as benzene and toluene, acetic acid Esters such as ethyl and butyl acetate, and aprotic polar solvents such as N, N-dimethylformamide and 1,3-dimethyl-2-imidazolidinone can be used. The progress of the reduction reaction can be monitored by the theoretical amount of hydrogen absorption or by thin layer chromatography or high performance liquid chromatography.

The target compound of the present invention, 1,3-bis (3-
Aminobenzoyl) benzene can be isolated by a method such as removing the catalyst and inorganic salts by hot filtration or extraction of the reaction solution obtained by these reduction reactions, and then, if necessary, concentrating. .

[0013]

The present invention will be described in more detail with reference to the following examples. Example 1 A glass reaction vessel equipped with a thermometer and a stirrer was charged with 505 g of 25% fuming sulfuric acid, and the internal temperature was cooled to about 0 ° C.
Then, 113.6 g of 1,3-dibenzoylbenzene
(0.4 mol) was gradually added so that the internal temperature did not rise above 10 ° C. While stirring this, the internal temperature was cooled to -5 ° C. Next, at the same temperature, 59.0 g of 94% fuming nitric acid
And 63.0 g of 25% fuming sulfuric acid were added dropwise over 6 hours. At this time, the internal temperature was kept in the range of −5 ° C. to 5 ° C. After completion of the dropwise addition, stirring was continued for a further 1 hour at a temperature in the range of -3C to 3C to complete the reaction. Next, this reaction solution was
1 ice water and stirred for 1 hour. This is filtered off,
After washing with water and drying, 146.3 g (yield 97.8%) of crude 1,3-bis (3-nitrobenzoyl) benzene was obtained. The purity by high performance liquid chromatography was as follows. HPLC analysis result 1- (2-nitrobenzoyl) -3- (3-nitrobenzoyl) benzene 3.8% 1,3-bis (3-nitrobenzoyl) benzene 81.7% 1- (3-nitrobenzoyl)- 3- (4-nitrobenzoyl) benzene 12.8% Other 1.7% Next, the above crude 1,3-bis (3-nitro) was placed in a glass container equipped with a stirrer, reflux condenser and thermometer. (Benzoyl) benzene (146.3 g, 0.39 mol) and ethyl alcohol (750 g) were charged, and a solution prepared by dissolving sodium hydroxide (9.8 g) in ethyl alcohol (162.0 g) under reflux of ethyl alcohol was added dropwise over 8 hours. did. After the completion of the dropwise addition, the reaction was continued while refluxing for another 2 hours. After cooling, the precipitated crystals were filtered, washed, and dried to obtain 126.8 g (86.7% yield) of 1,3-bis (3-nitrobenzoyl) benzene. The purity by high performance liquid chromatography was as follows.

HPLC analysis results 1- (2-nitrobenzoyl) -3- (3-nitrobenzoyl) benzene 0.1% 1,3-bis (3-nitrobenzoyl) benzene 98.1% 1- (3-nitrobenzoyl) benzene Benzoyl) -3- (4-nitrobenzoyl) benzene 1.4% Others 0.4% Next, the above 1,3-bis (3-nitrobenzoyl) was placed in a glass container equipped with a thermometer and a stirrer. Benzene 74.
8 g (0.2 mol), 134 g of iron powder and 680 ml of a 70% aqueous 2-methoxyethanol solution were charged.
The temperature was raised to ° C. Next, at the same temperature, 4.2 g of 36% hydrochloric acid
Was dissolved in 60 ml of a 70% aqueous 2-methoxyethanol solution and added dropwise over 2 hours. Stirring was continued for another hour to complete the reaction. After the completion of the reaction, the internal temperature was raised to 95 ° C., the mixture was filtered at the same temperature, and the filtrate was discharged into 4 l of water to precipitate crystals. This is filtered, washed, dried,
1,3-bis (3-aminobenzoyl) benzene 59.
6 g (yield 94.3%) was obtained. The purity by high performance liquid chromatography was 98.3% (Area%). Next, this crude ABB was heated and dissolved in 42.6 g of 36% hydrochloric acid and 120 ml of water, treated with activated carbon, and allowed to cool. The precipitated ABB hydrochloride was filtered, and 50%
It was dissolved in 500 ml of aqueous methanol solution and neutralized with dilute aqueous ammonia. The crystals are filtered, washed with water, dried and refined.
56.3 g of -bis (3-aminobenzoyl) benzene was obtained. The purity by high performance liquid chromatography is 9
It was 9.3%. Melting point: 114.2-116.9 ° C
Met.

EXAMPLE 2 A 97% sulfuric acid solution was placed in a glass container equipped with a stirrer and a thermometer.
70.0 g and 1,3-dibenzoylbenzene
8 g (0.2 mol) was charged and cooled while stirring and dissolving, and the temperature was kept at about 0 ° C. At the same temperature, specific gravity 1.5
35.2 g of fuming nitric acid of No. 2 was added dropwise over 3 hours. After completion of the dropwise addition, the cooling bath was removed, the temperature was raised to room temperature, and aging was performed for 4 hours to complete the reaction. The reaction solution was added to ice water 1.5
When the mixture was discharged to l, crystals precipitated. This was separated by filtration, washed with water and dried to obtain 72.5 g (96.9%) of crude 1,3-bis (3-nitrobenzoyl) benzene. The result of analysis by high performance liquid chromatography was as follows. HPLC analysis result 1- (2-nitrobenzoyl) -3- (3-nitrobenzoyl) benzene 8.8% 1,3-bis (3-nitrobenzoyl) benzene 65.1% 1- (3-nitrobenzoyl)- 3- (4-nitrobenzoyl) benzene 24.8% Other 1.3% This crude 1,3-bis (3-nitrobenzoyl) benzene 37.4 g (0.1 mol) and ethyl alcohol 187 g
And 3.7 g of polyethylene glycol having a molecular weight of 600 were charged into a reactor equipped with a thermometer, a stirrer and a reflux condenser, and 7.5 g of sodium hydroxide was previously dissolved in 120 g of ethyl alcohol under reflux of ethyl alcohol. The solution was added dropwise in 7 hours. After cooling, the precipitated crystals were filtered, washed, and dried to give 24.9 g (66.7%).
Of 1,3-bis (3-nitrobenzoyl) benzene was obtained. The purity by high performance liquid chromatography was as follows. HPLC analysis result 1- (2-nitrobenzoyl) -3- (3-nitrobenzoyl) benzene 0.4% 1,3-bis (3-nitrobenzoyl) benzene 98.0% 1- (3-nitrobenzoyl)- 3- (4-nitrobenzoyl) benzene 1.4% Other 0.2% Next, 5.6 g (0.015 mol) of the above 1,3-bis (3-nitrobenzoyl) benzene was added to 0.056 g of Raney nickel catalyst. And 30 g of ethyl alcohol in an autoclave, and reduced at a hydrogen pressure of 20 to 25 atm and a reaction temperature of 50 to 60 ° C. for 3 hours. Post-treatment and purification after the reaction were performed in the same manner as in Example 1 to obtain 1,3-bis (3-aminobenzoyl) benzene having a purity of 99.4% (Area%) by high performance liquid chromatography.

[0016]

According to the present invention, 1,3-bis (3-nitrobenzoyl) benzene of high purity is obtained in high yield from 1,3-dibenzoylbenzene as a raw material, and reduced to obtain 1,3-bis (3-nitrobenzoyl) benzene. It is intended to provide an industrial production method capable of producing economically useful 1,3-bis (3-aminobenzoyl) benzene in high yield and at low cost.

Continuation of front page (56) References JP-A-4-352750 (JP, A) Appl. Polym. Sci. (1981), 26 (11), 3805-3817. Org. Chem. (1975), 40 (8), 1090-1094 (58) Fields investigated (Int. Cl. ⁶ , DB name) C07C 225/00 C07C 221/00 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. A crude 1,3-bis (3) containing an isomer compound obtained by nitrating 1,3-dibenzoylbenzene.
-Nitrobenzoyl) benzene is treated with an alcohol in the presence of a basic compound to react substantially only isomers having a nitro group at the o- and / or p-position to give the corresponding alkoxy compound 1,3-bis (3-nitrobenzoyl) benzene, which is then reduced to obtain 1,3-bis (3-nitrobenzoyl) benzene, which is then reduced. Manufacturing method.