JP2005015382A - Method for producing alicyclic oxime - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an alicyclic oxime, by which the alicyclic oxime, especially cyclohexanone oxime, can be produced in high selectivity, high activity and high productivity. <P>SOLUTION: This method for producing the alicyclic oxime is characterized by oxidizing an alicyclic primary amine with molecular oxygen in the presence of a phenolic chain transfer agent in a liquid phase. <P>COPYRIGHT: (C)2005,JPO&amp;NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a corresponding cycloaliphatic oxime, particularly cyclohexanone oxime, with high selectivity, high activity, and high productivity by oxidizing a cycloaliphatic primary amine in a liquid phase. It is.
The obtained cycloaliphatic oxime is a compound useful as a resin additive, an antioxidant and the like, and is also useful as an intermediate material for pharmaceuticals, agricultural chemicals and the like. In particular, when the cycloaliphatic primary amine is cyclohexylamine, cyclohexanone oxime is obtained as the corresponding cycloaliphatic oxime. Cyclohexanone oxime is a useful compound as an intermediate of ε-caprolactam, which is a raw material for nylon-6.
[0002]
[Prior art]
Cycloaliphatic oximes are useful compounds as resin additives, antioxidants, and the like, and are also useful as intermediate materials for pharmaceuticals, agricultural chemicals, and the like. In particular, when the cycloaliphatic primary amine is cyclohexylamine, cyclohexanone oxime is obtained as the corresponding cycloaliphatic oxime. Cyclohexanone oxime is a useful compound as an intermediate of ε-caprolactam, which is a raw material for nylon-6.
[0003]
As a conventionally known method for producing cyclohexanone oxime, for example, a method using hydrogen peroxide as an oxidizing agent is (1) in the presence of a catalyst containing at least one metal selected from the group consisting of Mo, W and U. ([Patent Document 1] US Pat. No. 2,706,204), (2) A method using titanium silicalite or vanadium silicalite as a catalyst ([Non-Patent Document 1] TETRAHEDRON, 51 (41), 11305, ELSEVIERSCIENCE PRESS, Netherlands, 1995, and [Non-patent Document 2] CATAL. LETT., 28 (2-4), 263, KLUWER PUBLISHERS, 1994, Netherlands), as a method of using an organic hydroperoxide as an oxidizing agent. (3) Ti, V, Cr, Se, Zr, N , Mo, Te, Ta, W, Re, and U in the presence of a catalyst containing at least one metal selected from the group consisting of U (U.S. Pat. No. 3,960,954) Etc.
[0004]
In addition, as a method of using molecular oxygen as an oxidizing agent, (4) a method of performing in a gas phase in the presence of a solid catalyst containing SiO ₂ gel and γ-Al ₂ O ₃ and optionally combined with WO ₃ ([Patent Document 3] US Pat. No. 4,337,358, [Patent Document 4] US Pat. No. 4,504,681), (5) Tungsten oxide together with γ-Al ₂ O ₃ , SiO ₂ or hydrotalcite (Non-Patent Document 3) JOURNAL OF MOLECULAR CATALYSIS A; CHEMICAL 160, 393-402, 2000 and [Non-patent Document 4] PETROLEUM AND COAL 41, 177-180, 1999), (6) In the presence of a tertiary alcohol, preferably ammonia gas is present, A method of reacting in a liquid phase using a catalyst such as acid, phosphotungstic acid, molybdic acid, selenic acid, selenious acid ([Patent Document 5] described in Japanese Patent Publication No. 47-25324), (7) A method carried out in the liquid phase in the presence of a compound of at least one element belonging to Group 4 (Ti, Zr and Hf) of the periodic table ([Patent Document 6] Japanese Patent Laid-Open No. 2-29595 ( [Patent Document 7] corresponding to EP395046))) and the like.
[0005]
[Patent Document 1]
US Pat. No. 2,706,204 [Non-Patent Document 1]
TETRAHEDRON, 51 (41), 11305, ELSEVIERSCIENCE PRESS, Netherlands, 1995
[Non-Patent Document 2]
CATAL. LETT. , 28 (2-4), 263, KLUWER PUBLISHERS, 1994
[Patent Document 2]
US Pat. No. 3,960,954 [Patent Document 3]
US Pat. No. 4,337,358 [Patent Document 4]
US Pat. No. 4,504,681 [Non-Patent Document 3]
JOURNAL OF MOLECULAR CATALYSIS A; CHEMICAL 160, 393-402, 2000
[Non-Patent Document 4]
PETROLEUM AND COAL 41, 177-180, 1999
[Patent Document 5]
Japanese Patent Publication No. 47-25324 [Patent Document 6]
Japanese Patent Laid-Open No. 02-295956 [Patent Document 7]
European Patent No. 395046 [0006]
[Problems to be solved by the invention]
However, in these known methods, for example, the above methods (1) to (3) have a problem of using expensive hydrogen peroxide or organic hydroperoxide as an oxidizing agent. Are associated with known operational hazards associated with the handling of oxidants. Moreover, when using organic hydroperoxide, since the product derived from the reduction of hydroperoxide is contained in the reaction solution, there are problems such as complicated separation and purification operations.
In order to solve the above problems, the above methods (4) to (7) using molecular oxygen such as air or oxygen as an oxidizing agent have been proposed.
[0007]
The methods (4) and (5) use relatively severe gas phase operating conditions with a reaction temperature of 120 to 250 ° C. According to the study by the present inventors, under the operating conditions in the gas phase at a reaction temperature of 160 ° C. or higher, tar-like by-products and high-boiling organic carbonaceous matter accumulate on the surface of the catalyst, and the catalyst is easily deactivated. It turns out that it has the problem of being. In addition, the selectivity of the produced cyclohexanone oxime is as low as about 60 mol%, and there is a problem that the reaction amount per reaction space, that is, the productivity is low.
It is known that the oxidation reaction of the cycloaliphatic primary amine is an exothermic reaction, and at the same time, the target product oximes are thermally unstable. In the industrial implementation of this oxidation reaction, a liquid phase reaction that is easy to remove heat from the reaction is advantageous for a gas phase reaction, and the liquid phase reaction is performed under mild low temperature conditions that can suppress the sequential decomposition of the produced oxime. A production method for reacting underneath was desired.
[0008]
In the methods (6) and (7), the reaction is carried out under relatively mild conditions at a reaction temperature of 50 to 150 ° C. under liquid phase conditions. The method (6) shows a reaction example using t-butanol as a reaction solvent and phosphotungstic acid as a catalyst. However, the yield of cyclohexanone oxime is as low as several mole percent. The method (7) shows a reaction example using a titanium compound as a catalyst and using diethylene glycol dimethyl ether (diglyme), t-butanol, dimethylformamide, acetonitrile, triethylamine, and water as a reaction solvent. However, there is a problem that the selectivity of the oxime produced is as low as about 30-50 mol% and the productivity is low.
An object of the present invention is to solve the problems of the prior art and to provide a method for producing a cycloaliphatic oxime from a cycloaliphatic primary amine with high selectivity, high conversion, and high productivity. And
[0009]
[Means for Solving the Problems]
That is, in the present invention, when a cycloaliphatic oxime is produced by reacting a cycloaliphatic primary amine with molecular oxygen in a liquid phase, a phenol-based chain transfer agent, a phenol-based chain transfer agent, and various The cycloaliphatic oxime is produced by reacting in the presence of a catalyst comprising a metal, a metal oxide, a metal salt, or an organometallic compound.
According to the present invention, a cycloaliphatic oxime can be obtained with high selectivity, high activity, and high productivity, and operation related to handling of peroxide by using molecular oxygen as an oxidizing agent. This makes it possible to industrially produce cycloaliphatic oximes with a relatively simple operation.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is a method for producing a cycloaliphatic oxime by oxidizing a cycloaliphatic primary amine. The cycloaliphatic primary amine used in the present invention is preferably a saturated cycloaliphatic primary amine. For example, cyclohexylamine, cyclooctylamine, cyclopentylamine, cycloheptylamine, cyclododecanylamine, and the like can be used. Cyclohexanone oxime can be produced from cyclohexylamine, cyclooctanone oxime from cyclooctylamine, cyclopentanone oxime from cyclopentylamine, and cyclododecanone oxime from cyclododecanylamine. In addition, a cyclic aliphatic primary amine having a structure in which the cycloaliphatic residue is substituted with a substituent that is inert under the reaction conditions, for example, an alkyl group, such as methylcyclohexylamine, can also be used.
[0011]
The cycloaliphatic primary amine used in the present invention is most preferably cyclohexylamine. Examples of the method for producing cyclohexylamine include a direct amination reaction with cyclohexene and ammonia (Japanese Patent Laid-Open Nos. 57-4948, 64-75453, 9-194438, 10-72409). And amination reaction using cyclohexanol and ammonia (for example, Japanese Patent Publication No. 41-7575, Japanese Patent Publication No. 51-41627, Japanese Patent Publication No. 51-41627). The method described in JP-A-51-32601, JP-A-6-1758, etc.) or those manufactured by a known method by hydrogenation reaction of aniline, nitrobenzene, nitrocyclohexane, etc. are used. be able to.
[0012]
The purity of cyclohexylamine is, for example, a small amount of an organic compound derived from each method for producing cyclohexylamine, such as cyclohexanol, cyclohexanone, dicyclohexylamine, nitrocyclohexane, N-cyclohexylidene-cyclohexylamine, or a small amount of water. May be included. The purity of the cycloaliphatic primary amine is usually 95% by weight or more, preferably 98% by weight or more.
In the present invention, liquid phase oxidation is carried out in the presence of a phenol chain transfer agent or a phenol chain transfer agent and a catalyst composed of various metals, metal oxides, metal salts, or organometallic compounds.
By performing liquid phase oxidation in the presence of a phenol chain transfer agent as in the present invention, a reaction system that is extremely advantageous for the selectivity and activity of the partial oxidation reaction of a cyclic aliphatic primary amine can be obtained. .
[0013]
The chain transfer agent referred to in the present invention is one that can generate a stable radical by a chain transfer reaction with a growth radical, and a known phenol compound can be used as the phenol chain transfer agent to be used. For example, hydroquinone, monomethylhydroquinone, hydroquinone monomethyl ether, mono-t-butylhydroquinone, catechol, pt-butylcatechol, 2,6-di-t-butylphenol, 2,4-di-t-butylphenol, 2-t -Butyl-4,6-dimethylphenol, 2,6-di-t-butyl-4-methylphenol, 2,4,6-tri-t-butylphenol, n-octadecyl 3- (3,5-di-t -Butyl-4-hydroxyphenyl) propionate,
[0014]
3,9-bis (2- (3- (3-t-butyl-4-hydroxy-5-methylphenyl) -propionyloxy-1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro (5.5) undecane, triethylene glycol bis (3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate, tetrakis (methylene (3,5-di-butyl-4-hydroxyphenyl) propionate ) Methane, 2,6-di-t-butyl-4-ethylphenol, 2,4,6-tri-t-butylphenol, 2,6-di-t-butyl-4-hydroxymethylphenol, 2,2 ′ -Methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), 2,2'-methylenebis ( - cyclohexyl-4-methylphenol), 2,2'-methylenebis (4,6-di -t- butylphenol),
[0015]
2,2′-ethylidenebis (4,6-di-t-butylphenol), 4,4′-methylenebis (2,6-di-t-butylphenol), 4,4′-butylidenebis (3-methyl-6- t-butylphenol), 4,4′-thiobis (3-methyl-6-tert-butylphenol), 2,4-bis ((octylthio) methyl) -o-cresol, 2,2′-methylenebis (4-methyl-) 6-t-butylphenol), 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene and the like.
[0016]
Commercially available phenolic chain transfer agents include Irganox 1010, 1035, 1076, 1135, 1141, 1330, 245 (manufactured by Ciba Specialty Chemicals), Sumilizer BHT, BP-76, MDP-S, S, BBM-S. , WX-R, BP-101, GA-80 (manufactured by Sumitomo Chemical Co., Ltd.), ADK STAB AO-20, AO-30, AO-40, AO-50, AO-60, AO-70, AO-75, AO- 80, AO-330 (Asahi Denka Co., Ltd.) etc. can be obtained.
[0017]
Examples of the phenol chain transfer agent used in the present invention include hydroquinone, monomethylhydroquinone, hydroquinone monomethyl ether, catechol, irganox 1010 (pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4- Hydroxyphenyl) propionate]) is preferred.
The amount of the phenol chain transfer agent used is usually in the range of 0.001 to 1 mol, preferably 0.005 to 0.5 mol, per 1 mol of the cyclic aliphatic primary amine. The phenol chain transfer agent is usually dissolved in a reaction system containing a cyclic aliphatic primary amine as a raw material, and is added all at once, divided or continuously.
[0018]
As the catalyst in the present invention, various metals, metal oxides, metal salts, or organometallic compounds can be used. Elements belonging to Groups 4, 5, 6 and 7 of the Periodic Table Revised in 1991, aluminum, silicon And a catalyst containing at least one element selected from the group consisting of selenium. The element belonging to Groups 4, 5, 6 and 7 of the periodic table used in the present invention is preferably at least one element selected from the group consisting of titanium, zirconium, niobium, tantalum and tungsten, for example. . The catalyst is one kind of metal alone, one containing other metals, or various compounds such as metal oxides, organic acid salts, inorganic acid salts, halides, complexes, and heteropolyacids or salts thereof, and these are suitable. It may be supported on a catalyst carrier. The catalyst support can be used activated _{carbon, SiO 2, Al 2 O 3} , SiO 2 / Al 2 O 3, TiO 2, ZrO 2, ZnO, barium sulfate, potassium carbonate, diatomaceous earth, zeolite and the like.
[0019]
As a method for preparing the catalyst of the present invention, a known catalyst preparation method such as an adsorption method, an impregnation method, a coprecipitation method, a sol-gel method and the like can be used.
The liquid phase oxidation reaction in the present invention is performed without a solvent or in a solvent. When a solvent is used, examples of the solvent species include primary, secondary, or tertiary alcohols having 1 to 10 carbon atoms such as methanol, ethanol, isopropyl alcohol, and t-butyl alcohol; acetonitrile, benzonitrile, and the like. Nitrile compounds; aromatic hydrocarbons such as benzene and toluene; aliphatic and cycloaliphatic hydrocarbons having 6 to 10 carbon atoms such as n-hexane and cyclohexane; dimethylformamide; dimethyl sulfoxide; triethylamine; dimethoxyethane; dioxane; diglyme Water or the like can be used. Any of the above solvents can be used alone or as a mixture of two or more. The concentration of the cycloaliphatic primary amine when operating in the presence of a solvent is usually from 1 to 95% by weight, preferably 5%, based on the total weight of the solvent and the cycloaliphatic primary amine. ~ 70 wt%.
[0020]
The oxidation reaction of the cycloaliphatic primary amine in the present invention can be carried out in a liquid phase in a fixed bed or a suspension bed in a continuous manner or in a batch manner.
In the method of the present invention, a method in which a cycloaliphatic amine is reacted with molecular oxygen in the presence of a catalyst is used. Molecular oxygen is usually used in the form of air or a mixture with an inert gas such as nitrogen and helium, and the oxygen concentration is preferably 2 to 23% by volume, more preferably 3 Although it can be used in a range of ˜11% by volume, the oxygen concentration is preferably in a range where the reaction system does not take an explosive composition.
[0021]
The method of the present invention is characterized in that the cycloaliphatic primary amine oxidation reaction is carried out in the liquid phase. Therefore, the molecular oxygen introduced into the reaction system as a gas needs to be dissolved in the liquid phase in which the catalyst exists at an arbitrary concentration under the reaction conditions. For example, when an oxygen-containing gas is introduced under a temperature condition where the reaction substrate, product, or solvent mixture is refluxed under reduced pressure or normal pressure, the amount of oxygen dissolved in the liquid phase is extremely small, which is not preferable. As a method for dissolving oxygen in the liquid phase at an arbitrary concentration, a method in which an oxygen-containing gas is brought into contact with the liquid phase under a pressurized condition exceeding normal pressure is preferable.
[0022]
At this time, as the total pressure in the reaction system, for example, when a batch reaction is performed using a mixed gas of oxygen and inert gas, depending on the catalyst used and the reaction conditions, the reaction amount of the desired substrate amine, That is, in consideration of the amount of oxygen required for the reaction, a mixed gas with an inert gas having an arbitrary oxygen concentration may be supplied and reacted at a desired total pressure. The total pressure in the reaction system is usually in the range of 0.1 to 20 MPa, preferably 1 to 10 MPa.
[0023]
As a method for supplying the molecular oxygen-containing gas, for example, when a batch-type mixing and stirring tank reactor is used, the molecular oxygen-containing gas may be directly blown into the liquid phase portion formed in the reaction system. Alternatively, it may be introduced into the gas phase part existing in contact with the liquid phase part.
The supply of molecular oxygen consumed by the reaction can be performed by supplying pure oxygen, air, or diluted oxygen gas to the reaction system continuously or intermittently so as to maintain an arbitrary gas-phase oxygen partial pressure. In addition to this, for example, when carrying out a batch reaction, after introducing an oxygen-containing gas that retains a sufficient amount of oxygen in advance with respect to the reaction amount of the target substrate amine, supply oxygen consumption The reaction can be continued for an arbitrary time until the desired reaction rate is reached without performing the step.
[0024]
The reaction temperature in the present invention is usually preferably 50 to 150 ° C, more preferably 60 to 145 ° C, and most preferably 80 to 140 ° C. When the temperature rises above 150 ° C, the sequential decomposition or sequential oxidation reaction of the produced oxime proceeds, and the reaction selectivity to oxime tends to decrease due to the increase of high-boiling by-products. At low temperatures, the reaction rate tends to decrease.
The reaction time may be selected as appropriate by determining the target selectivity and yield of the desired cycloaliphatic oxime, and is usually several seconds to several hours.
[0025]
The amount of the catalyst varies depending on the catalyst type to be used, and may be an amount that provides a desired catalytic effect, and is usually 0.0001 / 1 to 100/1 by weight ratio with respect to the cyclic aliphatic primary amine. Preferably, it is in the range of 0.001 / 1 to 50/1.
In the oxidation reaction according to the present invention, although it varies depending on the catalyst type and reaction conditions, when cyclohexylamine is used as the cycloaliphatic primary amine, usually a small amount as a byproduct in addition to the target product cyclohexanone oxime. Cyclohexanone, N-cyclohexylidenecyclohexylamine, nitrocyclohexane and the like are produced. The produced cyclohexanone oxime is recovered from the reaction mixture in the reactor from which the catalyst has been separated by conventional means such as distillation or extraction, and can be brought to the desired purity by further separation means if necessary. Usually, unreacted cyclohexylamine is preferably recycled to the reaction vessel.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described with reference to examples and comparative examples.
[0027]
[Example 1]
(Preparation of catalyst)
Commercially available γ-alumina (specific surface area: 282 m ² / g) was dried at 120 ° C. overnight and used as a carrier. After dissolving 1.4 g of ammonium paratungstate pentahydrate in 60 g of water, 10 g of dried γ-alumina was added to form a suspension solution.
This suspension was placed in a glass flask, placed on a rotary evaporator, immersed in an oil bath at a temperature of 90 ° C. under normal pressure, and slowly stirred and mixed for 1.5 hours to obtain a slurry. Next, the slurry is concentrated to dryness, and the obtained powder is put into a glass tube furnace and fired at 500 ° C. for 4 hours under normal pressure while supplying air, and tungsten oxide is supported on alumina. A solid powder was obtained. The resulting solid powder had a tungsten content of about 9% by weight.
[0028]
(Oxidation reaction of cyclohexylamine)
Next, 0.1 g of the catalyst obtained above, 3.0 g of cyclohexylamine, and 0.03 g of hydroquinone as a phenol chain transfer agent were charged into a SUS316 high-pressure autoclave reactor (total volume 100 ml) equipped with a magnetic stirrer. After closing the autoclave and replacing the inside of the system with nitrogen gas, a mixed gas of nitrogen containing 7% oxygen was introduced into the gas phase portion, and the total pressure in the system was increased to 5 MPa. Next, the reactor was fixed to an oil bath, and the reaction temperature was 120 ° C. for 2 hours with stirring.
[0029]
After cooling, the residual pressure was removed, the autoclave was opened, the contents were diluted with ethanol, the catalyst was filtered off, and the filtrate was analyzed by gas chromatography.
The conversion of cyclohexylamine was 32.0 mol%, and the selectivity for cyclohexanone oxime was 80.4 mol%.
This is clearly superior in the selectivity and activity of cyclohexanone oxime compared to (4)-(7) described in the prior art. Moreover, the production amount (productivity) of cyclohexanone oxime per reaction space in this example is 0.13 kg / L-reaction space volume / time, and productivity is greatly improved as compared with the conventional technology. It is obvious.
[0030]
[Example 2]
The reaction was performed in the same manner as in Example 1 except that 0.03 g of catechol was used as the phenol chain transfer agent. As a result, the conversion of cyclohexylamine was 29.7 mol%, and the selectivity for cyclohexanone oxime was 80.5 mol%.
[0031]
[Example 3]
The reaction was conducted in the same manner as in Example 1 except that 0.03 g of hydroquinone monomethyl ether was used as the phenol chain transfer agent. As a result, the conversion of cyclohexylamine was 28.3 mol%, and the selectivity for cyclohexanone oxime was 79.8 mol%.
[0032]
[Example 4]
Irganox 1010 (pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]) manufactured by Ciba Specialty Chemicals was used as a phenol chain transfer agent. The reaction was carried out in the same manner as in Example 1 except that. As a result, the conversion of cyclohexylamine was 32.7 mol%, and the selectivity for cyclohexanone oxime was 82.0 mol%.
[0033]
[Example 5]
The reaction was performed in the same manner as in Example 1 except that the reaction temperature was 100 ° C. As a result, the conversion of cyclohexylamine was 13.0 mol%, and the selectivity for cyclohexanone oxime was 82.6 mol%.
[0034]
[Example 6]
The reaction was conducted in the same manner as in Example 1 except that the catalyst was not used. As a result, the conversion of cyclohexylamine was 11.5 mol%, and the selectivity for cyclohexanone oxime was 25.4 mol%.
[0035]
[Example 7]
The reaction was performed in the same manner as in Example 1 except that 12 g of t-butanol was used as a solvent. As a result, the conversion of cyclohexylamine was 8.3 mol%, and the selectivity for cyclohexanone oxime was 75.1 mol%.
[0036]
[Example 8]
Commercially available silica (specific surface area: 300 m ² / g) was vacuum-dried overnight at 120 ° C. and used as a carrier. After dissolving 1.3 g of ammonium metatungstate in 50 g of water, 10 g of dried silica was added to form a suspension solution. Using this suspension solution, a solid powder was prepared in the same manner as in Example 1 to obtain a solid powder in which tungsten oxide was supported on silica. The reaction was performed in the same manner as in Example 1 except that 0.1 g of the solid powder thus obtained was used as a catalyst. As a result, the conversion rate of cyclohexylamine was 27.4 mol%, and the selectivity of cyclohexanone oxime was 79.4 mol%.
[Example 9]
Commercially available zirconium tetranormal propoxide and titanium tetraisopropoxide were dissolved in about 2.5 times molar amount of hexylene glycol with respect to the total amount of these alkoxides, while stirring and mixing in a glass reactor at 120 ° C. In an oil bath for 3 hours. Next, the oil bath temperature is set to 90 ° C., and under stirring, the aqueous ethanol solution is hydrolyzed by dropwise addition of an amount such that the amount of water in the aqueous ethanol solution is 4 times the mole of the total amount of alkoxide. The product was obtained.
[0038]
The produced gel was aged overnight, then vacuum dried at 130 ° C., the dried gel was placed in a glass tube furnace, and baked at 550 ° C. for 5 hours while supplying air under normal pressure. A zirconia-titania composite oxide was obtained. The obtained composite oxide had a Zr / Ti atomic ratio of about 1.0. A catalyst was prepared in the same manner as in Example 1 except that the zirconia-titania composite oxide thus obtained was used as a carrier, and a solid powder containing tungsten oxide and zirconia-titania composite oxide was obtained. The resulting solid powder had a W / (Ti + Zr) atomic ratio of about 0.08. The reaction was performed in the same manner as in Example 1 except that 0.1 g of the solid powder thus obtained was used as a catalyst. As a result, the conversion of cyclohexylamine was 27.5 mol%, and the selectivity for cyclohexanone oxime was 78.7 mol%.
[Example 10]
Commercially available γ-alumina (specific surface area: 282 m ² / g) was vacuum-dried at 120 ° C. overnight. After dissolving 10.7 g of niobium hydrogen oxalate in 45 g of an aqueous oxalic acid solution, 10 g of dried γ-alumina was added dropwise to form a suspension solution. This suspension was placed in a glass flask, placed on a rotary evaporator, immersed in an oil bath at a temperature of 90 ° C. under normal pressure, and slowly stirred and mixed for 1.5 hours to obtain a slurry. Next, the obtained slurry was concentrated and dried, and the obtained aggregated dried product was further dried at 120 ° C. overnight. Next, the obtained powder was put into a glass tube furnace and subjected to a firing treatment at 500 ° C. for 4 hours while supplying air under normal pressure to obtain a solid powder in which niobium oxide was supported on alumina. . The niobium content of the obtained solid powder was about 9% by weight. The reaction was performed in the same manner as in Example 1 except that 0.1 g of the solid powder thus obtained was used as a catalyst. As a result, the conversion of cyclohexylamine was 29.1 mol%, and the selectivity for cyclohexanone oxime was 78.5 mol%.
Example 11
A homogeneous mixed alkoxide solution was prepared by mixing 0.52 g of commercially available tantalum pentaethoxide and 10.5 g of commercially available titanium tetraisopropoxide in a glass beaker. Next, 13.8 g of deionized water was added dropwise little by little while stirring with a glass rod to obtain a gel product. The gel product was air-dried at room temperature for about 4 hours, and further vacuum-dried at 120 ° C. overnight. Next, the dried gel was put into a glass tube furnace, and subjected to a baking treatment at 400 ° C. for 4 hours under normal pressure and air flow to obtain a solid powder containing niobium oxide and titania. The obtained solid powder had an Nb / Ti atomic ratio of about 0.035. The reaction was performed in the same manner as in Example 1 except that 0.1 g of the solid powder thus obtained was used as a catalyst. As a result, the conversion of cyclohexylamine was 24.3 mol%, and the selectivity for cyclohexanone oxime was 75.1 mol%.
[0041]
Example 12
10.5 g of commercially available titanium tetraisopropoxide was placed in a glass beaker, and 13.8 g of deionized water was dropped in small portions while stirring with a glass rod to obtain a gel product. The resulting gel was aged overnight, then vacuum dried at 130 ° C., the dried gel was placed in a glass tube furnace, and baked at 550 ° C. for 5 hours while supplying air under reduced pressure. A titania powder was obtained. The reaction was performed in the same manner as in Example 1 except that 0.1 g of the titania powder thus obtained was used as a catalyst. As a result, the conversion of cyclohexylamine was 31.2 mol%, and the selectivity for cyclohexanone oxime was 80.1 mol%.
[0042]
[Comparative Example 1]
The reaction was carried out in the same manner as in Example 1 except that no phenol chain transfer agent was used. As a result, the conversion of cyclohexylamine was 21.8 mol%, and the selectivity for cyclohexanone oxime was 78.1 mol%. The production amount (productivity) of cyclohexanone oxime per reaction space was 0.08 kg / L-reaction space volume / time.
[0043]
[Comparative Example 2]
The reaction was performed in the same manner as in Comparative Example 1 except that the reaction temperature was 100 ° C. As a result, the conversion of cyclohexylamine was 3.4 mol%, and the selectivity for cyclohexanone oxime was 70.8 mol%.
[0044]
[Comparative Example 3]
The reaction was carried out in the same manner as in Example 1 except that 12 g of t-butanol was used as a solvent without using a phenol chain transfer agent. As a result, the conversion of cyclohexylamine was 3.1 mol%, and the selectivity for cyclohexanone oxime was 52.7 mol%.
[0045]
[Comparative Example 3]
The reaction was carried out in the same manner as in Example 1 except that the catalyst and the radical initiator were not used. As a result, the conversion rate of cyclohexylamine was 0.7 mol%, and the selectivity of cyclohexanone oxime was 14.4 mol%.
[0046]
【The invention's effect】
According to the present invention, when producing a cycloaliphatic oxime by reacting a cycloaliphatic primary amine in the liquid phase with molecular oxygen in the presence of a phenolic chain transfer agent or a phenolic chain transfer agent and a catalyst, Oxime can be obtained with high selectivity, high activity and high productivity under mild temperature conditions. In addition, by using molecular oxygen as the oxidant, it is possible to avoid the operational complexity involved in handling peroxides and to industrially produce cyclic alicyclic oximes with relatively simple operations. Is possible.

Claims (6)

A process for producing a cycloaliphatic oxime, characterized in that a cycloaliphatic primary amine is oxidized with molecular oxygen in a liquid phase in the presence of a phenol chain transfer agent. The phenol chain transfer agent is at least one selected from hydroquinone, monomethylhydroquinone, hydroquinone monomethyl ether, catechol, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]. The method of claim 1, which is a seed. The process according to claim 1, wherein the oxidation reaction is carried out in the presence of a catalyst. 4. The method according to claim 3, wherein the catalyst contains at least one element selected from the group consisting of elements belonging to Groups 4, 5, 6 and 7 of the periodic table, aluminum, silicon and selenium. The method according to claim 4, wherein the element belonging to Groups 4, 5, 6 and 7 of the periodic table is at least one element selected from the group consisting of titanium, zirconium, niobium, tantalum and tungsten. . The method of claim 1, wherein the cycloaliphatic primary amine is cyclohexylamine.