JPH0449531B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing 9,10-phenanthrenequinone. Specifically, the present invention oxidizes phenanthrene with an organic peroxide in the liquid phase in the presence of a molybdenum-based catalyst to obtain 9,
The present invention relates to a method for obtaining 10-phenanthrenequinone. Regarding the production method of 9,10-phenanthrenequinone, a liquid phase oxidation method using a chromic acid compound has been known industrially. However, this method has the following problems. In other words, discharging chromium compounds outside the system is strictly restricted due to pollution and environmental hygiene reasons, and solutions to these problems, such as using them in closed systems and improving working environment standards, require enormous costs, and as a result, there are serious consequences. The product purity of 9,10-phenanthrenequinone is at most 70%.
It has been pointed out that the disadvantages are that it is relatively low and that chromium compounds are unavoidable. In addition to chromic acid compounds, many synthetic methods for producing 9,10-phenanthrenequinone are described in literature and patent specifications. For example, gas-phase catalytic oxidation of phenanthrene using a vanadium-based solid catalyst, potassium permanganate, periodic acid or potassium iodate and acetic acid, hypochlorite, ammonium cerium sulfate, hydrogen peroxide and acetic acid,
Liquid phase oxidation methods using organic peroxides and the like have been proposed. However, these methods have drawbacks such as low yields, expensive oxidizing agents, unavoidable corrosion of the equipment, and unavoidable contamination of impurities into the product, all of which make them unsuitable for industrial production. I haven't reached the point where I am. In producing 9,10-phenanthrenequinone from phenanthrene, the present inventors have intensively studied methods that can produce 9,10-phenanthrenequinone with high purity, high yield, and economically. The present invention was completed by discovering a method for obtaining 9,10-phenanthrenequinone in high quality and in extremely high yield. That is, the present invention can be specified as follows. (1) When producing 9,10-phenanthrenequinone by liquid-phase oxidation of phenanthrene using an organic peroxide, a molybdenum-containing compound is used as a catalyst, and the water produced by the reaction is used as an azeotrope. In the presence of an organic solvent that can be distilled out of the system, use an organic peroxide in the range of 0.5 to 4 moles per mole of phenanthrene supplied, and keep the conversion rate of phenanthrene in the range of 30 to 80%. A method for producing 9,10-phenanthrenequinone, characterized by: (2) The method described in (1) above, wherein the reaction temperature is in the range of 40 to 120°C. (3) The method described in (1) above, characterized in that acetylacetonate of a molybdenum compound is used as a catalyst. (4) The method described in (1), (2) or (3) above, wherein the raw material phenanthrene has a purity of 90% or more. According to the method of the present invention specified above, 9,10-
Not only can phenanthrenequinone be produced and obtained with high selectivity, only a small amount of diphenic acid (biphenyl-2,2'-dicarboxylic acid), which is a sequential oxide of 9,10-phenanthrenequinone, is produced as a by-product. Reaction conditions for production are proposed. The product thus obtained, 9,10-phenanthrenequinone, can be obtained with a purity of 95% or more simply by separating the reaction solution by cooling and crystallization operations. As mentioned above, if phenanthrene is oxidized in liquid phase with an organic peroxide using a molybdenum catalyst, 9,10
-It has been reported that phenanthrenequinone can be obtained, but [Zh.Obshch.Khim., Vol. 43(1),
215 (1973)], this report uses tertiary amyl hydroperoxide as the organic peroxide, and when the phenanthrene conversion rate is 45%, the selectivities for phenanthrenequinone and diphenic acid are 78%, respectively.
% and 22%. However, this example shows that 80
The results were obtained by reaction at ℃ for 12 hours, and the method specified in the present invention was not used, and although the reaction time was long, the conversion rate of phenanthrene was low.9,10
-Phenanthrenequinone selectivity is also low. Moreover, it does not disclose anything about the acquisition of 9,10-phenanthrenequinone of the high purity that the present invention was able to achieve, and furthermore, it does not provide any suggestion as to the state of the art that the present invention was able to achieve by performing the reaction in a short time. There's nowhere to go. Thus, the present inventors completed the present invention based on the following findings. That is, when phenanthrene is oxidized with an organic peroxide while distilling the water generated in the reaction in the presence of a molybdenum catalyst, especially acetylacetonate of a molybdenum compound, as an azeotrope together with an organic solvent such as benzene, the reaction occurs. In other words, the smaller the phenanthrene conversion rate, the higher the 9,10-phenanthrene quinone selectivity.If the phenanthrene conversion rate is increased to nearly 100%, the 9,10-phenanthrene quinone selectivity tends to be higher.
The phenanthrenequinone selectivity can drop below 80%, and therefore the phenanthrene conversion rate is 90%.
Below, preferably 80% or less9,
The 10-phenanthrenequinone selectivity can be maintained at 80% or more, and even 90% or more, and the product 9,10-phenanthrene can be obtained by simply cooling the reaction solution and crystallizing the reaction product. It has been discovered that high quality 9,10-phenanthrenequinone with a quinone purity of 90% or more, and even 98% or more, can be easily obtained. It is desirable that the phenanthrene used in the present invention be of high purity, but in view of economic efficiency, it can be used as long as it has a purity of 80% or more, particularly 90% or more. In an actual oxidation reaction, after the 9,10-phenanthrenequinone produced in the reaction is removed, phenanthrene can be recovered and reused from the reaction solution containing unreacted phenanthrene by a conventional distillation operation. However, the same reaction solution can be reused as it is by washing and purifying the by-product diphenoic acid and a small amount of impurities with water or alkaline water. General organic peroxides can be used in the present invention, and examples thereof include hydroperoxides of aliphatic hydrocarbons, alicyclic hydrocarbons, and alkyl-substituted aromatic hydrocarbons. However, tertiary butyl hydroperoxide or ethylbenzene hydroperoxide is preferred. The amount of organic peroxide used can be widely adopted per mole of phenanthrene.
It is desirable to use the amount within the range of 0.5 to 4 mol and keep the phenanthrene conversion within the range of 30 to 80%. As organic solvents that can be used in the present invention, any organic solvent can be used as long as it is stable against organic peroxides under the conditions of use, forms an azeotrope with water, and does not dissolve in each other and is easily separated. It is possible. In the present invention, the operation of distilling and removing the reaction product water generated in the oxidation reaction of phenanthrene to 9,10-phenanthrenequinone out of the reaction system as an azeotrope together with the organic solvent that is the reaction solvent is important. Unless the water produced during the reaction is removed from the reaction system, the oxidation reaction of phenanthrene will not proceed at all, and as a matter of course, the desired 9,10-phenanthrenequinone will not be produced. Therefore, in order to remove the product water generated in the reaction, an organic solvent that forms an azeotrope with water in a boiling state is used, the evaporated water and the organic solvent are condensed and separated, and only this organic solvent is released into the reaction system. By circulating and replenishing it, you can achieve that purpose. Examples include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, n-hexane, n-heptane, n-
Examples include aliphatic and alicyclic hydrocarbons such as octane and cyclohexane, organic carboxylic acid esters such as ethyl acetate, propyl acetate, butyl acetate, and especially benzene, ethylbenzene, n-
Hexane is preferred. The amount of organic solvent used can vary within wide limits. The reaction can be carried out in a uniform layer or in a heterogeneous layer, but in order to obtain high purity 9,10-phenanthrenequinone, the amount of phenanthrene is usually 1 to 50 times (parts by weight), preferably 3 to 30 times the amount of phenanthrene. Amount (parts by weight)
used within the range of As molybdenum-containing compounds that can be used as catalysts in the present invention, both inorganic and organic molybdenum compounds are effective, but those that are soluble in organic solvents are particularly desirable; examples include enols such as acetylacetonate. salts, naphthenic acids,
Examples include organic carboxylic acid salts such as stearic acid, carbonyl, etc., and acetylacetonate is particularly preferred. The amount of catalyst used can vary within a wide range, but is usually
It is used within the range of 0.001 mol to 0.2 mol, preferably 0.003 to 0.1 mol. The temperatures used in this invention vary widely depending on the reactivity of the reactants and the properties of the solvent, but are typically between 40
It is carried out at 120°C, preferably within the range of 60-100°C. The reaction is carried out under pressure conditions sufficient to maintain a liquid reaction phase, but can also be carried out under elevated or subatmospheric pressure, and is usually carried out at atmospheric pressure. The reaction time in the present invention varies depending on the desired phenanthrene conversion rate and 9,10-phenanthrenequinone selectivity, but is usually 1 to 14 hours, preferably 2 to 8 hours. The reaction mode can be either batchwise or continuous, and may be appropriately selected depending on the production scale. The present invention will be specifically explained below with reference to Examples, but it goes without saying that the present invention is not limited to these examples. Example 1 17.8 g of 99.9% pure phenanthrene, 350 g of benzene, and 0.8 g of bis(acetylacetonato)oxomolybdenum were placed in a four-neck glass flask equipped with a stirrer, a thermometer, and a condenser with a water separator.
34g of tertiary butyl hydroperoxide (purity 80%) was added dropwise over 30 minutes to the heated and stirred mixture, and the mixture was kept at a boiling state to condense the evaporated azeotrope of water and benzene in a condenser. The water and benzene were separated, and the benzene was directly refluxed into the flask and reacted in this way for 2 hours. The reaction solution was analyzed by gas chromatography and liquid chromatography, and the conversion rate of phenanthrene was 9.10.
- When the selectivity of phenanthrenequinone and diphenoic acid was investigated, the results were as follows. Phenanthrene conversion rate 30.0% 9,10-phenanthrenequinone selectivity 93.5% Diphenic acid selectivity 6.2% Examples 2 to 7 Example 1 except that the reaction time was 4, 6, 8, 10, 12, and 14 hours. When the reaction was carried out in exactly the same manner as above, the results shown in Table 1 were obtained. The reaction solution was cooled to 20°C, precipitated crystals were separated, and dried at 105°C. The obtained product was similarly analyzed for purity and liquid of 9,10-phenanthrenequinone.

[Table] Example 8 193 g of 92.5% pure phenanthrene, 3000 g of benzene, and 6 g of bis(acetylacetonato)oxomolybdenum were placed in 10 stainless steel reactors equipped with a stirrer, a thermometer, and a condenser with a water separator, and heated and stirred. After that, 360 g of tertiary butyl hydroperoxide (purity 80%) was added dropwise over 1 hour, and the water and benzene were separated by keeping it boiling and condensing the evaporated azeotropic mixture of water and benzene in a condenser. However, the benzene is directly refluxed into the reactor.
The reaction was allowed to proceed for 10 hours. The reaction solution was cooled to 20°C, precipitated crystals were separated, and dried at 105°C. The purity of 9,10-phenanthrenequinone and the liquid of the obtained product were analyzed in the same manner, and the following results were obtained. Phenanthrene conversion rate 70.1% 9,10-phenanthrenequinone selectivity 85.8% Diphenic acid selectivity 13.3% Product purity 93.3% Comparative Example 1 Reacted in exactly the same manner as in Examples 2 to 7 except that the reaction time was 16 hours. When carried out, the following results were obtained. Phenanthrene conversion rate 82.2% 9,10-phenanthrenequinone selectivity 73.2% Diphenic acid selectivity 24.8% Product purity 80.0% Comparative example 2 68 g of tertiary butyl hydroperoxide,
The reaction was carried out in exactly the same manner as in Examples 2 to 7 except that the reaction time was changed to 10 hours, and the following results were obtained. Phenanthrene conversion rate 84.5% 9,10-phenanthrenequinone selectivity 71.0% Diphenic acid selectivity 28.1% Product purity 82.8% When the product was washed with benzene, it increased to 94.5%.

Claims (1)

[Scope of Claims] 1. When producing 9,10-phenanthrenequinone by liquid-phase oxidation of phenanthrene using an organic peroxide, a molybdenum-containing compound is used as a catalyst, and the water produced by the reaction is , in the presence of an organic solvent that can be distilled out of the system as an azeotrope, 0.5% of the organic peroxide is added to 1 mole of phenanthrene supplied.
A method for producing 9,10-phenanthrenequinone, characterized in that the amount of 9,10-phenanthrenequinone used is within the range of 4 moles and the conversion rate of phenanthrene is kept within the range of 30 to 80%. 2. The method according to claim 1, wherein the reaction temperature is in the range of 40 to 120°C. 3. The method according to claim 1 or 2, characterized in that acetylacetonate of a molybdenum compound is used as a catalyst. 4. The method according to claim 1, 2 or 3, wherein the raw material phenanthrene has a purity of 90% by weight or more.