JP2007099746A - Method for producing phenol and cycloalkanone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing phenol and a cycloalkanone in high selectivity, by decomposing a cycloalkylbenzene hydroperoxide in the presence of a solid acid catalyst. <P>SOLUTION: This method for producing the phenol and the cycloalkanone comprises decomposing the cycloalkylbenzene hydroperoxide in the presence of the solid acid catalyst selected from a group consisting of acid-type montmorillonite, silica-alumina, a cation-exchange resin, a catalyst formed by supporting an acid functionality-developing component on a carrier, and a catalyst formed by insolubilizing heteropolyphosphoric acid in an organic solvent by exchanging a part of cation-exchange points thereof for Cs ions, so that the phenol and the cycloalkanone are obtained in the high selectivity. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing phenol and cycloalkanone, in which cycloalkylbenzene hydroperoxide is decomposed by a solid acid catalyst. The decomposed phenol can be converted to cyclohexanone as a raw material for synthesizing pharmaceutical intermediates and various functional materials, or by partial hydrogenation with a known catalyst. Moreover, the cycloalkanone produced | generated simultaneously can be induced | guided | derived to the various lactam which is a nylon raw material.

  As a method for producing phenol and cycloalkanone by decomposing cycloalkylbenzene hydroperoxide using a solid acid catalyst, Patent Document 1 discloses a method using zeolite. However, no other solid acid catalyst is described.

Special table 2003-529582 Inorg. Chem. 12, p. 331 (1973)

  An object of the present invention is to provide a method for producing phenol and cycloalkanone with high selectivity by decomposing cycloalkylbenzene hydroperoxide in the presence of a solid acid catalyst.

As a result of earnest research, the present inventor has found that the cation exchange point of the acid type montmorillonite, silica-alumina, cation exchange resin, acid functional component supported on the carrier, and heteropolyacid is partially Cs ion. We found that phenol and cycloalkanone can be obtained with high selectivity by decomposing cycloalkylbenzene hydroperoxide in the presence of a solid acid catalyst selected from the group consisting of those exchanged and insolubilized in organic solvents. The present invention has been reached.
That is, the present invention relates to acid-type montmorillonite, silica-alumina, a cation exchange resin, an acid function-expressing component supported on a carrier, and a cation exchange point of a heteropoly acid partially exchanged with Cs ions into an organic solvent. The present invention relates to a process for producing phenol and cycloalkanone, which comprises decomposing cycloalkylbenzene hydroperoxide in the presence of a solid acid catalyst selected from the group consisting of insolubilized substances.

  According to the present invention, phenol and cycloalkanone can be produced with high selectivity. Further, since the catalyst can be easily recovered, the catalyst can be easily recycled, and it is excellent as an industrial production method without the problem of corrosiveness of the apparatus.

The cycloalkylbenzene hydroperoxide used in the present invention is produced by oxidizing cycloalkylbenzene.
Examples of the cycloalkylbenzene include cyclopentylbenzene, cyclohexylbenzene, cycloheptylbenzene, cyclooctylbenzene, and cyclododecylbenzene. In these compounds, the hydrogen atom on the carbon atom may be substituted with a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), an alkyl group having 1 to 4 carbon atoms (methyl, ethyl, etc.), or the like. . Moreover, for example, 1,4-bicyclohexylbenzene and the like, which are composed of two or more alicyclic compounds and an aromatic ring, can also be mentioned.

The oxidation of cycloalkylbenzene is not particularly limited. For example, the cycloalkylbenzene is contacted with molecular oxygen in the presence of an oxidation catalyst.
As the molecular oxygen source, an oxygen-containing gas is usually used. As the oxygen-containing gas, for example, air, pure oxygen, or air or pure oxygen diluted with an inert gas such as nitrogen, argon, or helium may be used. Further, oxygen-enriched air obtained by adding pure oxygen to air can also be used.

  Examples of the oxidation catalyst include peroxides such as benzoyl peroxide and t-butyl hydroperoxide, and radical initiators such as N-hydroxyphthalimide and azoisobutyronitrile. Further, cycloalkylbenzene hydroperoxide generated by oxidation itself can be used as a catalyst.

The reaction temperature of the oxidation reaction is usually 0 to 180 ° C, preferably 50 to 130 ° C.
The reaction time varies depending on the reaction conditions, but is usually from several minutes to several hours.
The reaction pressure is usually 0.01 to 10 MPa, preferably 0.1 to 2 MPa.
In this oxidation reaction, a solvent inert to the reaction can also be used. Examples of the solvent include nitrile solvents such as acetonitrile, halogenated hydrocarbons such as ethylene dichloride and methylene chloride, and the like.

  The cycloalkylbenzene hydroperoxide thus obtained can be purified according to a conventional method, or the reaction mixture can be used as it is.

Cycloalkylbenzene hydroperoxide is decomposed by a solid acid catalyst to produce phenol and cycloalkanone.
Examples of solid acid catalysts include acid-type montmorillonite, silica-alumina, cation exchange resin, and sulfonic acid, perfluorosulfonic acid (such as Nafion (registered trademark)) and heteropolyacid as silica. , Alumina, silica-alumina, titania, zirconia, aluminosilicate, or mesoporous material, and those obtained by partially exchanging the cation exchange point of the heteropolyacid with Cs ions and so on. However, those in which an acid function-expressing component such as sulfonic acid, perfluorosulfonic acid or heteropolyacid is supported on the carrier, or those in which the cation exchange point of the heteropolyacid is partially Cs ion exchanged are preferred.

Here, the heteropolyacid is a condensed oxide of a coordination atom (polyatom) forming a basic skeleton and an oxoacid of a heteroatom, and is composed of hydrogen, a heteroatom, a polyatom, and oxygen.
Examples of the hetero atom include phosphorus, germanium, boron, and silicon.
Poly atoms include periodic table (according to IUPAC inorganic chemical nomenclature revised in 1989 using serial number 1-18 for group number), elements 4-7, specifically tungsten, molybdenum, niobium, tantalum, vanadium, etc. Is mentioned.
The atomic ratio of polyatoms / heteroatoms in the heteropolyacid is usually preferably from 2.5 to 12.
Heteropoly acids are not limited to monomers, and polymers such as dimers and trimers can also be used.
Specific examples include phosphotungstic acid, phosphomolybdic acid, silicotungstic acid, silicomolybdic acid, and phosphovanadomolybdic acid.
The heteropolyacid can be prepared, for example, according to the method described in Non-Patent Document 2, but a commercially available product can be used as it is. Alternatively, a heteropoly acid salt insolubilized by substituting a part of protons of these heteropolyacids with an alkali metal, alkaline earth metal, transition metal element or the like can be used.
Furthermore, a compound obtained by substituting a part of protons of the heteropolyacid with a nitrogen-containing compound such as ammonia or an amine compound (pyridine, n-butylamine, etc.) can also be used.

  As a carrier for supporting sulfonic acid and perfluorosulfonic acid as an acid function expression component, those having stability to sulfonic acid and perfluorosulfonic acid and a large specific surface area are preferable. Alumina, aluminosilicate or mesoporous material can be used. Here, the specific surface area and the pore diameter are not particularly limited, but those having a pore diameter larger than the molecular size of the cycloalkylbenzene hydroperoxide to be decomposed are preferable.

As a carrier carrying a heteropolyacid as an acid function-expressing component, a carrier that is stable with respect to the heteropolyacid and has a large specific surface area is preferable. For example, silica, alumina, silica-alumina, aluminosilicate, mesoporous material, etc. Can be used. Here, the specific surface area and the pore size are not particularly limited, but those having a pore size larger than the molecular size of the cycloalkylbenzene hydroperoxide to be decomposed and / or larger than the molecular size of the heteropolyacid are preferable. The specific surface area is preferably 100 m ² / g or more in order to maintain high dispersibility of the acid function-expressing component.

  Expression of acid function in solid acid catalyst in which components with acid function such as sulfonic acid, perfluorosulfonic acid and heteropoly acid are supported on a support such as silica, alumina, silica-alumina, titania, zirconia, aluminosilicate and mesoporous material The amount of the component supported is preferably in the range of 1 to 30 wt%, particularly preferably in the range of 5 to 20 wt%, based on the total weight of the solid acid catalyst.

Examples of a method for supporting these acid function-expressing components on the carrier include an evaporation to dryness method, a pore filling method, an ion exchange method, and a chemical modification method. Among these, the pore filling method, the ion exchange method, and the chemical modification method are preferable. The chemical modification method is a method in which a silane agent containing an acid functional component or a precursor thereof is used, and the silane agent is polycondensed on a carrier to carry the acid functional expression component or the precursor thereof by chemical bonding.
Specifically, 3-mercaptopropyltrimethoxysilane is polycondensed as a silane agent to the carrier such as silica, alumina, silica-alumina, titania, zirconia, aluminosilicate, mesoporous material, and then hydrogen peroxide solution. This is a method in which a mercapto group is converted to a sulfonic acid group by oxidation with a method such as the above.

  The amount of the solid acid catalyst used is preferably in the range of 0.01 wt% to 30 wt%, particularly preferably in the range of 0.05 wt% to 10 wt%, with respect to the cycloalkylbenzene hydroperoxide. When the amount used is small, a sufficient decomposition rate cannot be obtained, and when it is too large, the load of separation and recovery of the catalyst increases, which is not industrially preferable.

The reaction temperature for the decomposition reaction of cycloalkylbenzene hydroperoxide is preferably in the range of 0 to 100 ° C, preferably 20 to 50 ° C. If the temperature is lower than this range, sufficient decomposition activity cannot be obtained, while if it is higher, side reactions occur together and the selectivity is lowered.
The reaction time varies depending on the reaction conditions, but is usually from a few minutes to a few hours.
The reaction pressure is usually in the range of 0.01 to 10 MPa, preferably 0.1 to 2 MPa.
In this decomposition reaction, a solvent inert to the reaction can also be used. Examples of such a solvent include nitrile solvents such as acetonitrile and halogenated hydrocarbons such as ethylene dichloride and methylene chloride.

  The above oxidation and decomposition reaction can be carried out either batchwise or continuously, and the reaction method can be any method such as a fixed bed, a suspension bed, a fluidized bed, and a moving bed.

  After completion of the reaction, the produced cycloalkanone and phenol can be obtained by a known method. For example, after separating the acid catalyst from the reaction mixture with a filter or the like, cycloalkanone, phenol and unreacted cycloalkylbenzene can be fractionated by distillation.

  Further, the separated and recovered solid acid catalyst can be reused by, for example, firing treatment at a temperature at which organic substances adsorbed on the catalyst can be removed.

EXAMPLES The present invention will be specifically described below using examples, but the present invention is not limited to the following examples.
The specific surface area and pore diameter were measured by nitrogen adsorption measurement (pretreatment at 120 ° C. under vacuum for 30 minutes) using a high-speed specific surface area / pore diameter distribution measuring device (NOVA-1200; manufactured by Yuasa Ionics).

  The selectivity in the description of each example and comparative example was calculated by the following formula.

Reference Example 1 (Preparation of carrier)
After dissolving 60 mmol of dodecylamine in 1.2 mol of ethanol, 7.2 mol of ion-exchanged water was added to this solution and vigorously stirred, then 0.2 mol of tetraethylorthosilicate was added and vigorously stirred at room temperature for 1 hour. The resulting white gel was aged at room temperature for 48 hours, and then the white solid was collected by filtration, washed with ion-exchanged water and ethanol, and dried at 105 ° C. for 24 hours. Next, the temperature was raised from room temperature to 600 ° C. at a rate of 1.7 ° C./min in air, and firing was performed at 600 ° C. for 2 hours. When the obtained oxide was analyzed, it was confirmed to be a mesoporous material from adsorption isotherms by X-ray diffraction measurement and nitrogen adsorption measurement. The pore diameter and specific surface area were 2.5 nm and 1065 m ² / g, respectively. Hereinafter, abbreviated as MS.

Reference example 2 (catalyst preparation)
In a 50 ml eggplant flask, 1.0 g of phosphotungstic acid and 10 ml of ion exchange water were added and dissolved, and 5.0 g of the mesoporous material obtained in Reference Example 1 was added and stirred at room temperature for 5 minutes. The solvent was removed under reduced pressure using an evaporator to dryness, and the resultant was dried at 100 ° C. for 6 hours. The obtained catalyst is hereinafter referred to as PW ₁₂ / MS.

Example 1
In a 50 ml glass two-necked eggplant flask equipped with a condenser tube, 0.025 g (0.15 mmol) of N-hydroxyphthalimide (hereinafter referred to as NHPI) was weighed as an oxidation catalyst, and 2.400 g (15.0 mmol) of cyclohexylbenzene was added. After replacing the system three times with pure oxygen gas, a pure oxygen gas balloon was attached to the top of the cooling pipe and sealed. The reaction was started by immersing the flask in an oil bath set at 110 ° C. in advance. After 4 hours, the flask was removed from the oil bath and air-cooled to room temperature to release unreacted oxygen gas. 10 ml of n-hexane was added to the resulting reaction solution (the production rate of cyclohexylbenzene hydroperoxide with respect to cyclohexylbenzene was 25%), and 0.030 g of PW ₁₂ / MS was added as an acid catalyst. After stirring at room temperature for 2 hours, cyclohexanone, phenol, unreacted cyclohexylbenzene and the like produced by an internal standard method (internal standard substance: dodecane) using gas chromatography with an FID detector were quantified. As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 94%, and the selectivity of phenol was 92% based on cyclohexylbenzene hydroperoxide. Separation of the acid catalyst PW ₁₂ / MS from the reaction solution could be easily performed with a glass filter.

Example 2
A cyclohexylbenzene hydroperoxide was prepared in the same manner as in Example 1 except that Nafion ((Nafion) registered trademark) -supported silica (SAC-13; manufactured by NE Chemcat) was used as the acid catalyst, and the solvent was changed to acetonitrile instead of n-hexane. Preparation and decomposition reactions were performed. As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 91%, and the selectivity of phenol was 95% based on cyclohexylbenzene hydroperoxide. Separation of the acid catalyst (Nafion (trademark) -supported silica) from the reaction solution could be easily performed with a glass filter.

Example 3
A cyclohexylbenzene hydroperoxide was prepared and decomposed in the same manner as in Example 2 except that the acid catalyst was Cs _2.5 H _0.5 PW ₁₂ O ₄₀ . As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 88%, and the selectivity of phenol was 85% based on cyclohexylbenzene hydroperoxide. Separation of the acid catalyst (Cs _2.5 H _0.5 PW ₁₂ O ₄₀ ) from the reaction solution could be performed with a glass filter.

Examples 4-5
Weigh 0.025 g (0.15 mmol) of N-hydroxyphthalimide (NHPI) as an oxidation catalyst in two 50 ml glass two-necked eggplant flasks equipped with cooling tubes, and add 2.400 g (15.0 mmol) of cyclohexylbenzene. After replacing the inside of the system three times with pure oxygen gas, a pure oxygen gas balloon was attached to the top of the cooling pipe and sealed. The reaction was started by immersing each flask in an oil bath set at 110 ° C., and after 4 hours, each flask was taken out of the oil bath and air-cooled to room temperature to release unreacted oxygen gas. 10 ml of acetonitrile is added to the reaction liquid in each flask (cyclohexylbenzene hydroperoxide production rate of 25% with respect to cyclohexylbenzene), and Nafion ((Nafion) registered trademark) -supported silica (SAC-13; manufactured by NE Chemcat) is used as the acid catalyst. 0.030 g) was added. Each flask was kept at a temperature of 25 ° C. and 50 ° C. respectively, and the reaction solution was stirred for 30 minutes, then rapidly cooled to room temperature, and the reaction solution in each flask was subjected to an internal standard method using gas chromatography with an FID detector (internal Cyclohexanone, phenol, unreacted cyclohexylbenzene and the like produced by standard substance: dodecane) were quantified. At this time, the decomposition rate of cyclohexylbenzene hydroperoxide was 100% in all cases.

Comparative Example 1
To a 50 ml glass two-necked eggplant flask equipped with a condenser, weigh 0.025 g (0.15 mmol) of N-hydroxyphthalimide (NHPI) as an oxidation catalyst, add 2.400 g (15.0 mmol) of cyclohexylbenzene, and add pure oxygen. After replacing the system three times with gas, a pure oxygen gas balloon was attached to the top of the cooling pipe and sealed. This was immersed in an oil bath set at 110 ° C. in advance to start the reaction. After 4 hours, the reaction was taken out from the oil bath, air-cooled to room temperature, and unreacted oxygen gas was released. 10 ml of acetonitrile was added to the resulting reaction solution (the yield of cyclohexylbenzene hydroperoxide with respect to cyclohexylbenzene was 25%), and Nafion ((Nafion) registered trademark) -supported silica (SAC-13; manufactured by NE Chemcat) was used as the acid catalyst. 0.030 g was added. This was stirred at a temperature of 80 ° C. for 30 minutes and then rapidly cooled to room temperature. The resulting reaction solution was cyclohexanone and phenol produced by an internal standard method (internal standard substance: dodecane) using gas chromatography with an FID detector. Unreacted cyclohexylbenzene and the like were quantified. At this time, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%.

Example 6 (Recycling of acid catalyst)
In the same manner as in Example 2, preparation and decomposition reaction of cyclohexylbenzene hydroperoxide were performed. As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 88%, and the selectivity of phenol was 85%. The acid catalyst (silica carrying Nafion (registered trademark)) was separated from the reaction solution using a glass filter and dried in air at 100 ° C. for 12 hours.
Using the recovered acid catalyst thus obtained, cyclohexylbenzene hydroperoxide was prepared and decomposed again in the same manner as in Example 2.
As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 88%, and the selectivity of phenol was 85% based on cyclohexylbenzene hydroperoxide. Separation of the acid catalyst (silica supported by Nafion (registered trademark)) from the reaction solution could be performed with a glass filter.
After this re-recovered acid catalyst was dried in air at 100 ° C. for 12 hours, the total amount of elements was quantified by fluorescent X-rays.

Reference Example 3 (Preparation of catalyst)
60 mmol of dodecylamine was dissolved in 1.2 mol of ethanol, and 7.2 mol of water was added thereto and stirred vigorously. Next, 0.2 mol of tetraethylorthosilicate and 0.02 mmol of 3-mercaptopropyltrimethoxysilane were added and stirred vigorously at room temperature for 1 hour. The resulting white gel was aged at room temperature for 48 hours, and then the white solid was collected by filtration, washed with water and ethanol, and dried at 105 ° C. for 24 hours. Next, Soxhlet extraction was performed in 500 ml of ethanol. The obtained white solid was oxidized at room temperature with 30 wt% aqueous hydrogen peroxide. When this oxidized white solid was dispersed in ion-exchanged water and subjected to potentiometric titration analysis, the sulfonic acid group per unit weight was 0.92 mmol / g, and it was not oxidized due to the difference in sulfonic acid group from the total sulfur amount in the catalyst. The thiol group of was 0.23 mmol / g. Further, it was confirmed to be a mesoporous material by X-ray diffraction measurement. Hereinafter, abbreviated as MS-SO ₃ H.

Example 7
In a 50 ml glass two-necked eggplant flask equipped with a condenser tube, 0.025 g (0.15 mmol) of N-hydroxyphthalimide (hereinafter referred to as NHPI) was weighed as an oxidation catalyst, and 2.400 g (15.0 mmol) of cyclohexylbenzene was added. After replacing the system three times with pure oxygen gas, a pure oxygen gas balloon was attached to the top of the cooling pipe and sealed. The reaction was started by immersing the flask in an oil bath set at 110 ° C. in advance. After 4 hours, the flask was removed from the oil bath and air-cooled to room temperature to release unreacted oxygen gas. 10 ml of n-hexane was added to the resulting reaction solution (the production rate of cyclohexylbenzene hydroperoxide with respect to cyclohexylbenzene was 25%), and 0.100 g of MS-SO ₃ H was added as an acid catalyst. After stirring at 50 ° C. for 2 hours, cyclohexanone, phenol, unreacted cyclohexylbenzene and the like produced by an internal standard method (internal standard substance: dodecane) using gas chromatography with an FID detector were quantified. As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 90% on the basis of cyclohexylbenzene hydroperoxide, and the selectivity of phenol was 89%. Separation of the acid catalyst MS-SO ₃ H from the reaction solution could be easily performed with a glass filter.

The separated acid catalyst MS-SO ₃ H was washed with 10 ml of ethanol and then dried at 100 ° C.
Using the recovered catalyst thus obtained, cyclohexylbenzene hydroperoxide was prepared and decomposed in the same manner as described above. As a result, the decomposition rate of cyclohexylbenzene peroxide was 83%, the selectivity of cyclohexanone was 88%, and the selectivity of phenol was 87% based on cyclohexylbenzene hydroperoxide.
The acid catalyst was recovered again and all elements were quantified by fluorescent X-ray. As a result, the Si / S ratio (atomic ratio) representing the catalyst composition was unchanged before and after use, and the mesopore structure by X-ray diffraction was maintained. .

Example 8
Preparation and decomposition reaction of cyclohexylbenzene hydroperoxide were performed in the same manner as in Example 2 except that the acid catalyst was an ion exchange resin (Amberlyst 15DRY; manufactured by Organo). As a result, the decomposition rate of cyclohexylbenzene hydroperoxide was 100%, the selectivity of cyclohexanone was 95%, and the selectivity of phenol was 95% on the basis of cyclohexylbenzene hydroperoxide. Separation of the acid catalyst (ion exchange resin) from the reaction solution could be performed with a glass filter.

Example 9
0.045 g (0.28 mmol) of N-hydroxyphthalimide (hereinafter referred to as NHPI) was measured as an oxidation catalyst in a 50 ml glass two-necked eggplant flask equipped with a cooling tube, and 0.49 g (2.00 mmol) of cyclododecylbenzene was added. After replacing the system three times with pure oxygen gas, a pure oxygen gas balloon was attached to the top of the cooling pipe and sealed. The reaction was started by immersing the flask in an oil bath set at 120 ° C. in advance. After 6 hours, the flask was removed from the oil bath and air-cooled to room temperature to release unreacted oxygen gas. 5 ml of acetonitrile was added to the resulting reaction solution (25% yield of cyclododecylbenzene hydroperoxide with respect to cyclododecylbenzene), and Nafion ((Nafion) registered trademark) -supported silica (SAC-13; NE Chemcat) was used as the acid catalyst. 0.030 g) was added. After stirring at 50 ° C for 2 hours, cyclododecanone, phenol and unreacted cyclododecylbenzene produced by the internal standard method (internal standard substance: dodecane) using gas chromatography with an FID detector were quantified in the reaction solution. did. As a result, the conversion of cyclododecylbenzene hydroperoxide was 6.8%, cyclododecanone selectivity was 72%, and phenol selectivity was 74% based on cyclododecylbenzene hydroperoxide. Separation of the acid catalyst from the reaction solution could be easily performed with a glass filter.

Claims (4)

  A group consisting of acid-type montmorillonite, silica-alumina, cation exchange resin, an acid functional component supported on a carrier, and a cation exchange point of a heteropoly acid partially exchanged with Cs ions and insolubilized in an organic solvent A process for producing phenol and cycloalkanone, which comprises decomposing cycloalkylbenzene hydroperoxide in the presence of a solid acid catalyst selected from:   The method for producing phenol and cycloalkanone according to claim 1, wherein the acid function-expressing component is sulfonic acid, perfluorosulfonic acid, or heteropolyacid.   The method for producing phenol and cycloalkanone according to claim 2, wherein the carrier is silica, alumina, silica-alumina, titania, zirconia, aluminosilicate or mesoporous material. The production method according to claim 1, wherein the solid acid catalyst is recycled.