KR100255547B1 - Method for 1,4-naphthoquinones and anthraquinones using the [2+4] deils-alder reaction - Google Patents

Abstract

PURPOSE: Provided is a method for synthesizing 1,4-naphthoquinones and anthraquinones using£2+4|Diels-Alder reaction in high yield where resultant compounds from the£2+4|Diels-Alder reaction are continuously dehydrogenated in the same reactor as the£2+4|Diels-Alder reaction is carried out. Also, nitro compounds acting as solvent and oxidant are used in the£2+4|Diels-Alder reaction so that amine compounds can be obtained. CONSTITUTION: The preparation method of 1,4-naphthoquinones and anthraquinones comprises the process of reacting quinones selected from 1,4-benzoquinone, 2-methylbenzoquinone, 1,4-naphthoquinone with 1,3-butadienes selected from 1,3-butadiene, isoprene, 2,3-dimethyl-butadiene by using£2+4|Diels-Alder reaction where nitro compounds selected from nitrobenzene, p-nitrotoluene, and p-nitrophenol are used as both solvent and oxidant; continuously dehydrogenating resultant compounds. In the method, the temperature of the£2+4|Diels-Alder reaction is 140 to 210deg.C.

Description

Method for preparing 1,4-naphthoquinone compound or anthraquinone compound using [2 + 4] dils-alder reaction

In the present invention, a quinone compound (quinones) and a 1,3-butadiene compound (1,3-butadienes) are reacted with a nitro compound as a solvent and an oxidizing agent. [2 + 4] Diels-Alder ), And continuously oxidative dehydrogenation reaction in the same reactor to prepare 1,4-naphthoquinone compound (1,4-naphthoquinones) or anthraquinone compound (anthraquinones) at the same time the nitro compound is reduced The present invention relates to a method for obtaining an amine compound.

1,4-naphthoquinone is most commonly used as an anthraquinone synthetic intermediate, and is used as a regulator of polymerization, a curing agent for polyester production, a stabilizer for transformer oil, a corrosion inhibitor, etc. Can be classified.

1) Method by liquid phase oxidation of naphthalene

2) Method by Gas Phase Oxidation of Naphthalene

3) Method by [2 + 4] Diels-Alder Reaction

The first of these methods uses an oxidizing agent such as chromic acid, chromium trioxide (CrO ₃ ) or manganese sulfate (MnSO ₄ ) to oxidize naphthalene, or a catalyst such as cerium or cobalt complexes to generate heavy metal pollution. There is plenty of room. The second method uses vanadium pentoxide (V ₂ O ₅ ) as a catalyst to oxidize naphthalene by gas or air containing oxygen at 250 ~ 450 ℃ and 0.1 ~ 1MPa. In this method, phthalic anhydride is produced as a reaction by-product, and a process for separating it is essential. In addition, this method could reduce, but not completely eliminate, pollution caused by the use of heavy metals. The third method uses intermediates such as 4a, 5,8,8a-tetrahydronaphthoquinone produced by the [2 + 4] dils-Alder reaction of 1,4-benzoquinone compounds and 1,3-butadiene compounds. After separation, it is a method of producing 1,4-naphthoquinone compounds by dehydrogenation using an oxidizing agent. This method can produce various kinds of 1,4-naphthoquinone-based compounds, and can prevent the occurrence of heavy metal pollution by using oxidizing agents that do not produce pollution, and dehydrogenation in the dehydrogenation process. There has also been proposed a method for preparing a 1,4-naphthoquinone-based compound using hydrogen peroxide, sodium chlorate-based oxidant, oxygen, etc. as an oxidant that does not cause pollution after the reaction.

Unsubstituted 1,4-benzoquinone in the 1,4-benzoquinone compound has two dienophiles in the molecule, which can cause the [2 + 4] Diels-Alder reaction twice. . Two dienophiles of 1,4-benzoquinone are capable of performing two [2 + 4] dils-alder reactions in succession, and using this, anthraquinone-based compounds are the same as those for preparing 1,4-naphthoquinone compounds. The preparation of compounds is possible.

Anthraquinone is known as an important raw material of dyes such as acid and base dyes, bat dyes, disperse dyes and reactive dyes, and is also widely used as a raw material for producing hydrogen peroxide using autoxidation. Ulmann's Encyclopedia of industry chemistry, Vol. 2, pp. 347-354, VCH 1985, Germany). Hydrogen peroxide can be produced by reacting a metal peroxide with an inorganic acid, but at present, most of the patents related to anthraquinone-based compounds have been produced by an automatic oxidation reaction applying an oxidation / reduction reaction of anthraquinone. And US Patent No. 5,624,543 (1997), PCT WO 95/10480, USP 5,374,339 (1994), and the like.

Known methods for producing anthraquinone compounds can be broadly divided into four.

1) Oxidation of anthracene

2) using the Friedel-Crafts reaction

3) Method by oxidation of indane

4) Using the [2 + 4} Diels-Alder Reaction

Among the methods of oxidizing anthracene, bichromate, nitric acid, oxygen, chlorine, ozone, etc. may be used as an oxidizing agent, and the method of using chromium has the advantage of oxidizing anthracene faster than other impurities. However, there is a difficulty in removing heavy metals from waste water due to heavy metal pollution. The method using the Friedel-Crafts reaction is difficult to remove aluminum from the wastewater by reacting phthalic anhydride and benzene under a catalyst of aluminum trichloride (AlCl ₃ ). The third method, oxidation by indane, has the advantage that relatively cheap styrene can be used as an intermediate for the synthesis of derivatives, while phthalic anhydride is produced as a reaction by-product. That's how we're working on it. However, the common problems in the above three methods include the difficulty of waste catalyst treatment, the complexity of the reaction apparatus, and the hassle to enter the next reaction through the separation process. There is a problem that can not.

In the fourth method of the anthraquinone preparation, 1,4-naphthoquinone is reacted with 1,3-butadiene and [2 + 4] dils-Alder, and then the [2 + 4] dils-Alder reaction product is subjected to oxygen under basic conditions. It is a method of obtaining by dehydrogenation by using, and it does not require special equipment for the reaction, and if the temperature is raised without a catalyst by the reaction by heat, there are few side reactions, and thus the reaction selectivity is good and many studies have been conducted. USP 4,369,140 (1983) synthesized naphthoquinone by vapor oxidation from naphthalene, followed by 1,3-butadiene and [2 + 4] dils-alder reaction to 1,4,4a, 9a-tetra A method for preparing anthraquinone is described by preparing a hydroanthraquinone and then oxidizing it in air in the presence of aqueous sodium hydroxide. In addition, since there is no need for a special catalyst, there is an advantage of eliminating the occurrence of pollution, Japanese Patent Application Publication Nos. 51-8256, 51-8257, 51-54540, 51-118754 and 51-138666 (1976). However, these methods have a problem of separation and yield reduction by separating the reaction product after the [2 + 4] dils-Alder reaction and then dehydrogenating. [USP No. 5,387,704 (1995) and Japanese Patent Publication No. 6-047564 (1994)]

The amines produced at the same time as the quinones in the patent document are produced by reacting hydrogen with a catalyst such as palladium, platinum, etc. under high temperature and high pressure. However, this manufacturing method is not an industrially desirable reduction method because complicated safety devices are essential. Using organic gas as a hydrogen donor instead of catalytic hydrogenation using hydrogen gas as a source of hydrogen can be a useful way to make amine compounds from nitro compounds, the most known of which is cyclohexene. Invention patents relating to the reaction of producing benzene, ethylbenzene and styrene at the same time using vinylcyclohexene as a hydrogen donor and nitrobenzene as a hydrogen acceptor are produced. Patents in this regard include USP Nos. 4,300,010 (1981), 4,339,622 (1982), 4,375,571 (1983), and many of the inventions are reactions using catalysts. In addition, USP No. 4,152,340 (1979) may be used to produce anthraquinone by using nitrobenzene for the production of quinones and at the same time using a basic catalyst. 1,4,4a, 9a-tetrahydroanthraqui There is British Patent No. 895,620 (1962) for preparing anthraquinones from rice fields, but their reaction yields are quite low.

In the present invention, a quinone compound and a 1,3-butadiene compound are continuously subjected to a [2 + 4] dils-Alder reaction and a dehydrogenation reaction in a same reactor using a nitro compound as a reaction solvent and an oxidizing agent. 2 + 4] shortened the process of separating the Diels-Alder reaction product to increase the yield of the final product as well as to find the advantage that the amines can be obtained at the same time by-product to complete the present invention.

That is, the 4a, 5,8,8a-tetrahydronaphthoquinone-based compound, which is a [2 + 4] dils-alder product of the 1,4-benzoquinone-based compound and the 1,3-butadiene-based compound in the present invention, 1 Although, 4,4a, 9a-tetrahydroanthraquinone compounds and 1,4,4a, 5,8,8a, 9a, 10a-octahydroanthraquinone compounds are stable compounds that can be separated, they are not separated. [1 +]-naphthoquinone compound or anthraquinone compound was prepared by continuously proceeding the [2 + 4] dils-alder reaction and the dehydrogenation reaction in one vessel, and simultaneously using the nitro compound as a solvent and an oxidizing agent. It relates to a method for obtaining an amine compound. This eliminates the trouble of separation and yield reduction caused by separating the reaction product after the [2 + 4] dils-Alder reaction and then going through a dehydrogenation process. In addition, it is possible to prepare the amine compound in a simple and safe manner instead of the method of preparing the amine compound using an industrially complex apparatus under high temperature and high pressure conditions.

In the same reactor, a quinone compound and a 1,3-butadiene compound are reacted with a [2 + 4] dils-alder reaction using a nitro compound as a reaction solvent and an oxidizing agent, and oxidative dehydrogenation is continuously performed. The present invention relates to a method for preparing a 4-naphthoquinone-based compound or an anthraquinone-based compound and simultaneously producing an amine compound as a by-product.

Specifically, 1,4-benzoquinone, 2-methyl-1,4-benzoquinone, and 2-methyl- are dienophiles of the [2 + 4] dils-alder reaction. 1,4-butadiene, isoprene, 2,3-dimethyl-1 as dienes using 1,4-benzoquinone, 1,4-naphthoquinone, etc. [2 + 4] Diels-Alder reaction using, 3-butadiene (2,3-dimethyl-1,3-butadiene) to obtain 4a, 5,8,8a-tetrahydronaphthoquinones (4a, 5,8 , 8a-tetrahydronaphtoquinones), 1,4,4a, 9a-tetrahydroanthraquinones (1,4,4a, 9a-tetrahydroanthraquinones), 1,4,4a, 5,8,8a, 9a, 10a-octahydroanthra Quinones (1,4,4a, 5,8,8a, 9a, 10a-octahydroanthraquinones) and the like are prepared, and the reaction product is continuously subjected to a separation process using nitro compounds as oxidants and solvents in the same reactor. Dehydrogenation to produce a 1,4-naphthoquinone compound or an anthraquinone compound and simultaneously a nitro compound A method for obtaining this reduced amine compound.

In the present invention, the diene was reacted with [2 + 4] Diels-Alder using 1 to 2.5 moles with respect to 1 mole of dienophile.

As the nitro compound used as the reaction solvent and the oxidizing agent, an aromatic nitro compound and an aliphatic nitro compound can be used. Of the present invention, nitrobenzene, p-nitrotoluene, and p-nitrophenol ), Etc., and it was appropriate to use in the range of 2-10 mol with respect to 1 mol of dienophiles. Since the nitro compound is reduced to produce amines such as aniline, p-aminotoluene, and p-aminophenol, there is an advantage in that industrial processes can produce amines at the same time as producing quinones. In addition, the nitro compound not involved in the reaction can be recovered and used again, and also used as a recrystallization solvent of the quinone compound, which has a characteristic of being obtained by crystallizing relatively pure quinones after the reaction.

The reaction temperature of the present invention is suitable for 140 ~ 210 ℃, the lower the reaction temperature has the disadvantage of the generation of hydroquinone and side reactions and the reaction time is long, the reaction proceeds in a short time as the reaction temperature increases If too high, however, the reactants tend to carbonize, leading to reduced yields.

In the present invention, a homogeneous reaction in a flask was used. Analysis of the reactants was confirmed by using nuclear magnetic resonance (NMR) spectra and gas chromatography-mass spectrometry detector (GC-MSD), and quantitative analysis using gas chromatography. To confirm, the analysis was conducted under the following conditions, and the component ratio was used in terms of area ratio.

Cappillary column: ULTRA 1 (Crosslinked Methyl Silicone Gum)

50m × 0.22m × 0.33㎛

Carrier: nitrogen

Head pressure: 18psig

Oven: 150 ℃ (2min) to 280 ℃, β = 20 ℃ / min

Detector and temperature: FID (280 ℃)

Spilit ratio: 50: 1

Make up gas flowrate: 38ml

Hereinafter, the present invention will be described in detail with reference to Examples. However, the present invention is not limited only to the examples.

Example 1

A 250 ml three-necked flask was equipped with a reflux condenser and a heating mantle was installed, followed by 1,4-benzoquinone (4.2 g, 50 mmol) and 2,3-dimethyl-1,3-butadiene (9.7 g, 120 mmol). Dissolve in nitrobenzene (36.9 g, 300 mmol) with stirring. Set the temperature to 200 ℃ by using a temperature controller, and then proceed to dehydrogenation through [2 + 4] Dilse-Alder reaction and gradually increase the temperature to 200 ℃. Then, take a sample every 2 hours after the reaction time. Dissolved in a solvent mixed with chloroform and a small amount of ethanol, and then confirmed and quantified using gas chromatography, the conversion is shown in Table 1, and the resulting amine compound is aniline. The correct structure was confirmed by filtering the aniline and nitrobenzene produced after the reaction by filtration under reduced pressure, and then mixing the crude compound with cold ethanol, stirring it again, drying it in an oven, and then using hex magnetic resonance spectra. The analysis was confirmed.

Production rate of 2,3,6,7-tetramethylanthraquinone with reaction time Reaction time % Conversion /% selection 2 hr 4 hr 6 hr 8 hr 10 hr 100/43100/59100/75100/92100/94

As a result of the above, the longer the reaction time, the higher the production rate of 2,3,6,7-tetramethylanthraquinone.

In this reaction, the conversion rate refers to the rate at which the starting materials react and the product is formed. The selectivity refers to the rate at which the desired product is formed, such as anthraquinones or naphthoquinones.

Example 2

Except for changing the amount of nitrobenzene in Example 1 was carried out in the same manner as in Example 1 to obtain the conversion and selectivity shown in Table 2.

Production rate of 2,3,6,7-tetramethylanthraquinone according to the molar ratio of nitrobenzene / 1,4-benzoquinone Molar ratio % Conversion /% selection Response time (hr) 23610 100/96100/91100/94100/61 441010

Example 3

Except having changed the kind of 1, 4- quinone and the kind of 1, 3- butadiene, it carried out similarly to Example 1, and obtained conversion and selectivity shown in Table 3. Each product was identified using nuclear magnetic resonance spectra and gas chromatography-mass spectrometry detectors.

Yields and yields of different quinones and butadienes Quinones Butadienes product % Conversion /% selection Response time (hr) Aniline yield (%) 1,4-benzoquinone 1,3-butadiene Anthraquinone 100/86 6 30 Isoprene 2,6- or 2,7-dimethyl-anthraquinone 100/92 10 35 2,3-dimethyl-1,3-butadiene 2,3,6,7-tetramethylanthraquinone 100/94 10 28 1,4-naphthoquinone 1,3-butadiene Anthraquinone 100/79 3 22 Isoprene 2-methylanthraquinone 100/85 6 20 2,3-dimethyl-1,3-butadiene 2,3-dimethylanthraquinone 100/90 6 19 2-methyl-1,4-benzoquinone Isoprene 2,6-or2,7-dimethyl-naphthoquinone 100/78 3 (180) 17 2,3-dimethyl-1,3-butadiene 2,6,7-trimethylnartoquinone 100/85 3 (150) 13

The yield of aniline in this example was calculated by expressing the% of the aniline production relative to the product as the area% of aniline / (area% of aniline + area% of anthraquinones).

As a result of reacting the quinones while changing the butadienes, the selectivity was improved when 2,3-dimethyl-1,3-butadiene was used as compared to 1,3-butadiene.

Example 4

All conditions were the same as Example 1 except having changed the reaction temperature in the said Example 1.

Yield over reaction temperature and time Reaction temperature (℃) % Conversion /% selection Response time (hr) 140160180200 100/19100/50100/84100/94 10101010

The higher the reaction temperature, the higher the selectivity was obtained.

Example 5

All of the conditions were the same as in Example 1 and only the type of nitro compound was changed instead of nitrobenzene.

Yield according to the kind of nitro compounds Nitro compounds % Conversion /% selection Nitrobenzene p-nitrotoluene 100/94 100/90

The amine compound produced according to the kind of nitro compound used was aniline for nitrobenzene and p-aminotoluene for p-nitrotoluene.

The present invention solves the problem of separation trouble and yield reduction by continuously dehydrogenation reaction in the same reactor without separating the [2 + 4] dils-alder reaction product separately. By using a nitro compound as a oxidant, an amine compound can be prepared as a by-product at the same time in a simple and safe manner.

Claims (5)

In the method for preparing a 1,4-naphthoquinone compound or an anthraquinone compound by reacting a quinone compound with a 1,3-butadiene compound with [2 + 4] dils-Alder, the nitro compound is used as a reaction solvent. 2 + 4] A method of preparing a 1,4-naphthoquinone compound, an anthraquinone compound, and an amine compound simultaneously by continuously conducting an oxidative dehydrogenation reaction in the same reactor. The quinone compound is any one selected from 1,4-benzoquinone, 2-methylbenzoquinone, 1,4-naphthoquinone, and the 1,3-butadiene compound is 1,3-butadiene, A method for producing a 1,4-naphthoquinone compound or an anthraquinone compound, which is any one selected from isoprene and 2,3-dimethyl-butadiene. The 1,4-naphthoquinone-based compound according to claim 1, wherein the nitro compound is any one selected from nitrobenzene, p-nitrotoluene, and p-nitrophenol, and uses 2 to 10 molar ratio with respect to the 1,4-quinone compound. Method for producing a compound or an anthraquinone compound. The method for producing a 1,4-naphthoquinone compound or anthraquinone compound according to claim 1, wherein the 1,3-butadiene compound is used in a 1 to 4 molar ratio with respect to the 1,4-benzoquinone compound. The method for producing a 1,4-naphthoquinone compound or anthraquinone compound according to claim 1, wherein the reaction temperature is 140 to 210 ° C.