JP2001253847A - Method for producing (hydroxyalkyl)cycloaliphatic carboxylic acids - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for enabling the industrial and efficient production of (hydroxyalkyl)cycloaliphatic carboxylic acids at low costs. SOLUTION: The (hydroxyalkyl)cycloaliphatic carboxylic acids are produced by performing the ring hydrogenation reaction (hydrogen reduction reaction) and hydrolysis reaction of (acyloxyalkyl)aromatic carboxylic acids as starting substances.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing (hydroxyalkyl) cycloaliphatic carboxylic acids, and more particularly to a method for producing a (hydroalkyl) cycloaliphatic carboxylic acid as a starting material. reduction)
The present invention relates to a method for producing (hydroxyalkyl) cycloaliphatic carboxylic acids by performing a reaction and a hydrolysis reaction.

[0002]

2. Description of the Related Art Generally, bifunctional compounds having two functional groups are used as raw materials for various synthetic resins, various chemicals such as solvents, or raw materials for these chemicals. In particular, (hydroxyalkyl) cycloaliphatic carboxylic acids, particularly hydroxyalkylcyclohexanecarboxylic acids, which are a kind of compounds having an alcoholic hydroxyl group and a carboxyl group in the same molecule, can be used as homopolyesters or ethylene glycol. Is a very useful compound as a raw material for producing a copolyester.

[0003] As a method for producing 4-hydroxymethylcyclohexanecarboxylic acids, which are a kind of the hydroxyalkyl cyclic aliphatic carboxylic acids, for example, French Patent No. 1,447,136 discloses that p-hydroxymethylbenzoic acid is used. The reaction temperature was 200 ° C. and the reaction pressure was 1.47 × 10 ⁷ Pa using Raney nickel as a catalyst.
A method for hydrogenating a benzene ring under the following reaction conditions is disclosed. Further, for example, Japanese Patent Application Laid-Open No. 9-59188 discloses that a reaction temperature of 160 ° C. and a reaction pressure of 4.9 × 10 ⁶ Pa using terephthalic acid as a reaction substrate and tin-modified lanerthenium as a catalyst. A method for hydrogenating a benzene ring is disclosed.

[0004]

However, there is still no method for inexpensively and industrially producing p-hydroxymethylbenzoic acid used as a raw material in the method disclosed in French Patent No. 1,447,136. It has not been established, and the above publication does not disclose any method for producing the same. That is, it is difficult to industrially obtain p-hydroxymethylbenzoic acid as a raw material.

Further, when a nickel or cobalt catalyst such as Raney nickel or Raney cobalt is used as the ring hydrogenation catalyst, a very high hydrogen partial pressure is required when hydrogenating the benzene ring. Since it is required to carry out the reaction at a high temperature, special reaction equipment that can withstand the reaction conditions is required. For this reason, the 4-hydroxymethylcyclohexanecarboxylic acid, which is the target substance, cannot be produced at low cost. On the other hand, when a catalyst containing palladium or platinum is used as the ring hydrogenation catalyst, the reaction conditions are relatively mild, but the hydroxymethyl group is susceptible to hydrogenolysis, and 4-methylcyclohexanecarboxylic acid is easily formed as a by-product. , 4-hydroxymethylcyclohexanecarboxylic acid has a problem that the selectivity decreases. Further, the above-mentioned French Patent No. 1,447,1
In the method disclosed in No. 36, the catalytic activity of the catalyst used is low. Therefore, in order to improve the production efficiency, a large amount of the catalyst must be used for p-hydroxymethylbenzoic acid as a reaction substrate.

Therefore, for the above reasons, the method disclosed in French Patent No. 1,447,136 cannot be said to be an industrial production method.

On the other hand, according to the method described in JP-A-9-59188, 4-hydroxymethylcyclohexanecarboxylic acid can be obtained under relatively mild reaction conditions.

However, Japanese Patent Application Laid-Open No. 9-59188 describes
In order to obtain 4-hydroxymethylcyclohexanecarboxylic acid from terephthalic acid as a raw material, hydrogen reduction of a benzene ring and a carbonyl group is required in the method described in JP-A No. Require 5 moles of hydrogen. That is, Japanese Patent Application Laid-Open No. 9-5
The method described in 9188 is a hydrogen-consuming reaction that consumes a large amount of hydrogen. In addition, the above-mentioned reaction is a reaction in which water is by-produced from terephthalic acid as a raw material, and the basic unit of the raw material increases. From these facts, the above-mentioned Japanese Patent Application Laid-Open No.
When the method described in JP-A-59188 was used, the above-mentioned 4-
Hydroxymethylcyclohexanecarboxylic acid cannot be produced at low cost.

Further, since 4-hydroxymethylcarboxylic acid produced by the above reaction and terephthalic acid as a raw material are hardly soluble in each other, a special purification is required to obtain 4-hydroxymethylcyclohexanecarboxylic acid having high purity. Equipment is required.

Further, the production of tin-modified ruthenium used as a catalyst requires special equipment for melting ruthenium metal and aluminum metal at a high temperature for producing a Raney alloy. For this reason, there is a problem that the production cost of the catalyst increases, and as a result, the production cost of the target product, 4-hydroxymethylcyclohexanecarboxylic acid, increases. Therefore, it is hard to say that the above method is also an industrial production method.

That is, the above-mentioned conventional production methods are all unsuitable for industrial implementation, and have a problem that 4-hydroxymethylcyclohexanecarboxylic acids cannot be produced at low cost and industrially. ing. Therefore, a method for industrially, efficiently and inexpensively producing (hydroxyalkyl) cycloaliphatic carboxylic acids such as the above-mentioned 4-hydroxymethylcyclohexanecarboxylic acids, which are a kind of hydroxyalkylcyclohexanecarboxylic acids. Is expected.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to produce (hydroxyalkyl) cycloaliphatic carboxylic acids such as hydroxyalkylcyclohexanecarboxylic acids industrially and efficiently. An object of the present invention is to provide a method that can be manufactured at low cost.

[0013]

DISCLOSURE OF THE INVENTION The inventors of the present application have made intensive studies on a method for producing a (hydroxyalkyl) cyclic aliphatic carboxylic acid. As a result, a (hydroxyalkyl) cycloaliphatic carboxylic acid is produced industrially, efficiently and inexpensively by performing a ring hydrogenation reaction and a hydrolysis reaction using (acyloxyalkyl) aromatic carboxylic acids as a starting material. I found that I can do it. Also,
(Hydroxyalkyl) cycloaliphatic for industrially, efficiently and inexpensively producing (hydroxyalkyl) cycloaliphatic carboxylic acids by ring-hydrogenating (acyloxyalkyl) aromatic carboxylic acids It has been found that (acyloxyalkyl) cyclic aliphatic carboxylic acids, which are intermediates (precursors) for the production of carboxylic acids, can be produced industrially, efficiently and at low cost. Also,
By hydrogen reducing the benzene ring of (hydroxyalkyl) aromatic carboxylic acids using a specific catalyst, the benzene ring of (hydroxyalkyl) aromatic carboxylic acids can be hydrogen reduced under milder conditions than before. As a result, they have found that a (hydroxyalkyl) cyclic aliphatic carboxylic acid can be industrially produced more efficiently and inexpensively. Further, as a pre-reaction, for example, an inexpensive alkyl-substituted aromatic compound such as xylene and a carboxylic acid such as acetic acid are used as starting materials, and a partial oxidation reaction is performed using a catalyst having a specific composition in the presence of oxygen. As a result, it has been found that (acyloxyalkyl) aromatic carboxylic acids, which are the raw materials of (hydroxyalkyl) cyclic aliphatic carboxylic acids, can be produced industrially, efficiently and at low cost, and the present invention has been completed. Reached.

That is, the method for producing a (hydroxyalkyl) cyclic aliphatic carboxylic acid according to the present invention, in order to solve the above-mentioned problems, reduces the aromatic ring compound group of an (acyloxyalkyl) aromatic carboxylic acid by hydrogen. To produce (acyloxyalkyl) cycloaliphatic carboxylic acids, and (acyloxyalkyl) obtained by the above step.
Hydrolyzing the cyclic aliphatic carboxylic acids.

The method for producing a (hydroxyalkyl) cycloaliphatic carboxylic acid according to the present invention includes a step of hydrolyzing the (acyloxyalkyl) cycloaliphatic carboxylic acid in order to solve the above problems. It is characterized by:

Furthermore, in order to solve the above-mentioned problems, the method for producing (hydroxyalkyl) cycloaliphatic carboxylic acids according to the present invention comprises hydrolyzing (acyloxyalkyl) aromatic carboxylic acids to form (hydroxyalkyl) It is characterized by comprising a step of producing an aromatic carboxylic acid and a step of hydrogen-reducing the aromatic ring compound group of the (hydroxyalkyl) aromatic carboxylic acid obtained in the above step.

Furthermore, in order to solve the above-mentioned problems, the method for producing a (hydroxyalkyl) cycloaliphatic carboxylic acid according to the present invention comprises the steps of: The method is characterized by including a step of hydrogen reduction using a catalyst containing at least one element selected from ruthenium.

In order to solve the above-mentioned problems, the process for producing (acyloxyalkyl) cyclic aliphatic carboxylic acids according to the present invention reduces the aromatic ring compound group of (acyloxyalkyl) aromatic carboxylic acids by hydrogen. It is characterized by including a step.

The (acyloxyalkyl) cyclic aliphatic carboxylic acids according to the present invention have the general formula (1) R ⁶ COO—CR ¹ R ² —Z—COOH to solve the above-mentioned problems. 1) (wherein, Z represents a divalent or higher alicyclic compound group having 6 or more carbon atoms, R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² represents a hydrogen atom, a carbon atom Represents an alkyl group of formulas 1 to 3, or an -OCOR ⁵ group, wherein R ⁵ has 1 to 4 carbon atoms
Wherein R ⁶ is a substituted carbon number of 1 to
6 alkyl groups, C1-6 alkene groups, C1
Alkyne group or substituted benzene).

Furthermore, in order to solve the above-mentioned problems, the catalyst according to the present invention is a catalyst used for hydrogen reduction of an aromatic ring compound group of (hydroxyalkyl) aromatic carboxylic acids, and is selected from rhodium and ruthenium. It is characterized by containing at least one element.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION The process for producing (hydroxyalkyl) cyclic aliphatic (alicyclic) carboxylic acids according to the present invention comprises: starting from (acyloxyalkyl) aromatic carboxylic acids as a ring hydrogenation reaction and hydrolyzing. This is a method for producing (hydroxyalkyl) cycloaliphatic carboxylic acids by carrying out a decomposition reaction, more specifically, from (acyloxyalkyl) aromatic carboxylic acids via (acyloxyalkyl) cycloaliphatic carboxylic acids. To produce (hydroxyalkyl) cycloaliphatic carboxylic acids, or from (acyloxyalkyl) aromatic carboxylic acids to (hydroxyalkyl) cycloaliphatic carboxylic acids via (hydroxyalkyl) aromatic carboxylic acids And a method for producing

The (acyloxyalkyl) aromatic carboxylic acids used as a raw material in the present invention include a divalent or higher valent group (aromatic ring compound group) obtained by removing two or more hydrogen atoms from an aromatic ring compound, and an acyloxyalkyl group. Any compound having a group and a substituent such as a carboxyl group in the same molecule may be used, and is not particularly limited.
Specifically, for example, the general formula ^{(2) R 6 COO-CR} 1 R 2 -Ar-COOH ...... (2) ( wherein, Ar represents a divalent or more aromatic ring compound group, R ¹
Represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms,
R ² is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or -
Represents an OCOR ⁵ group, R ⁵ represents an alkyl group having 1 to 4 carbon atoms, R ⁶ represents an alkyl group having 1 to 6 carbon atoms, an alkene group having 1 to 6 carbon atoms, 6 representing an alkyne group or substituted benzene).

The aromatic ring compound group contained in the (acyloxyalkyl) aromatic carboxylic acids is more specifically a divalent or higher valent carbocyclic aromatic compound group (monocyclic or condensed polycyclic aromatic compound). A) or a divalent or higher valent heteroaromatic compound group (monocyclic or condensed polycyclic heteroaromatic compound group). More specifically, a divalent or higher valent aromatic compound group refers to a benzene ring from which two or more hydrogen atoms have been removed, a condensed ring such as a naphthalene ring, a heterocyclic ring such as a pyridine ring,
And so on. Further, the (acyloxyalkyl) aromatic carboxylic acids may have a functional group that is inactive to a reaction such as an oxidation reaction, a ring hydrogenation reaction, and a hydrolysis reaction described below.

The (acyloxyalkyl) aromatic carboxylic acids include, for example, o-, m-, p
O-, m-, p-acetoxyalkylbenzoic acids such as -acetoxymethylbenzoic acids and the like, but are not particularly limited.

The above (acyloxyalkyl) aromatic carboxylic acids include, for example, a compound represented by the following general formula (3): CHR ¹ R ² —Ar— (R ³ ) _n (3) (where Ar is a divalent or higher aromatic ring) Represents a compound group, R ¹
Represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms,
R ² is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or -
Represents an OCOR ⁵ group, R ³ represents an alkyl group having 1 to 4 carbon atoms, a —COOH group, a —CHO group, a —CH ₂ R ⁴ group, or a —COOR ⁵ group, and n represents an integer of 1 to 5. , R ⁴ represents a halogen atom, an —OH group, or —OCOR ⁵
Wherein R ⁵ represents an alkyl group having 1 to 4 carbon atoms) and a carboxylic acid in the presence of oxygen, containing an element belonging to Group VIII of the periodic table. By performing partial oxidation (oxidative esterification reaction) using, it can be obtained industrially efficiently and inexpensively. That is, in the (acyloxyalkyl) aromatic carboxylic acids represented by the general formula (2), the substituent represented by R ⁶ CO— in the formula is, for example, derived from the above carboxylic acids.

The divalent or higher valent aromatic ring compound group represented by Ar in the above general formula (3) refers to a divalent or higher valent group obtained by removing two or more hydrogen atoms from an aromatic ring compound. Specifically, a divalent or higher valent carbocyclic aromatic compound group (monocyclic or condensed polycyclic aromatic compound group) and a divalent or higher valent heteroaromatic compound group (monocyclic or condensed polycyclic group) Heteroaromatic compound group). More specifically, the divalent or higher aromatic ring compound group refers to a benzene ring from which two or more hydrogen atoms have been removed, a condensed ring such as a naphthalene ring, a heterocyclic ring such as a pyridine ring, and the like.

The above-mentioned alkyl-substituted aromatic compounds are not particularly limited as long as they are compounds having a substituent such as a partially oxidizable alkyl group in the molecule. Also,
Alkyl-substituted aromatic compounds may have a functional group that is inert to the oxidation reaction according to the present invention.

The alkyl-substituted aromatic compounds include:
Specifically, for example, xylene, ethyltoluene, n-
O-, m-, p-alkyl-substituted toluenes such as propyltoluene, isopropyltoluene and butyltoluene;
O-, m-, p-dialkyl-substituted benzenes such as diethylbenzene; o-, m-, p-alkyl-substituted hydroxymethylbenzenes such as hydroxymethyltoluene and (hydroxymethyl) ethylbenzene; methylbenzaldehyde, ethylbenzaldehyde and the like , O-, m-, p
-Alkyl-substituted benzaldehydes; methylbenzoic acid,
O-, m-, p-alkyl-substituted benzoic acids such as ethylbenzoic acid; o-, m-, p-alkyl-substituted benzoic esters such as methyl methylbenzoate and methyl ethylbenzoate; methylbenzyl acetate and the like O-, m-, p-
Carboxyalkyl-substituted toluenes; o-, m-, p-dicarboxyalkyl-substituted benzenes such as xylylene diacetate; dialkyl-substituted naphthalenes such as dimethylnaphthalene; alkyl-substituted naphthalenecarboxylic acids such as methylnaphthoic acid; dimethylpyridine (lutidine ) And the like.

Among the alkyl-substituted aromatic compounds exemplified above, o-, m-, p-xylene, o-, m-, p-hydroxymethyltoluene, o-, m-, p-methylbenzaldehyde, o- , M-, p-methylbenzoic acid, o
-, M-, p-methylbenzyl acetate, and o
-, M-, p-xylylene diacetate is more preferred.

As the carboxylic acids used as a raw material in the method for producing the (acyloxyalkyl) aromatic carboxylic acids, monocarboxylic acids are suitable, and specifically, for example, acetic acid, propionic acid, butanoic acid, acrylic acid And aliphatic carboxylic acids such as methacrylic acid; and aromatic carboxylic acids such as benzoic acid, but are not particularly limited. Of the carboxylic acids exemplified above, acetic acid is more preferred.

The molar ratio of the carboxylic acid to the alkyl-substituted aromatic compound is not particularly limited.
More preferably, the molar ratio is in the range of 1 to 20 moles. If the above molar ratio is less than the same molar ratio, carboxylic acids will be insufficient, so that it may not be possible to efficiently produce (acyloxyalkyl) aromatic carboxylic acids. On the other hand, even when the carboxylic acid is used in a molar ratio exceeding 20 times the molar ratio, compared with the case where the carboxylic acid is used in the above molar ratio,
Further improvement in yield and the like can hardly be expected. In addition, since a large amount of carboxylic acids is used, the reaction apparatus and a recovery device for recovering excess carboxylic acids are increased in size, and the production cost including the recovery cost may increase.

The catalyst (oxidation reaction catalyst) used in the above (acyloxyalkyl) aromatic carboxylic acid production method is a catalyst containing an element belonging to Group VIII of the periodic table (hereinafter referred to as a Group VIII element). Specific examples of the Group VIII element include nickel, palladium, platinum, and rhodium. These Group VIII elements may be used alone or in combination of two or more. Of the Group VIII elements, palladium is particularly preferred.

When the group VIII element is palladium, the catalyst may be simple palladium such as palladium metal, palladium black, palladium oxide, or the like. It may be a body.

As the above-mentioned palladium compound, specifically, for example, palladium nitrate, palladium sulfate, palladium acetate, ammonium hexachloropalladate,
Sodium hexachloropalladate, potassium hexachloropalladate, ammonium tetrachloropalladate, sodium tetrachloropalladate, potassium tetrachloropalladate, potassium tetrabromopalladate, potassium tetracyanopalladate, palladium chloride, palladium bromide, palladium iodide , Chlorocarbonyl palladium, potassium dinitrosulfite palladium, dinitrodiamine palladium, tetraamminepalladium chloride, tetraamminepalladium nitrate, cis-dichlorodiaminepalladium, trans-dichlorodiaminepalladium, bistriphenylphosphinepalladium dichloride, dichloro (ethylenediamine) palladium, etc. Although it is mentioned, it is not particularly limited. Also, metal palladium or palladium oxide can be supported on a carrier as a palladium compound. These palladium compounds may be used alone,
Further, two or more kinds may be used in combination. Among the palladium compounds exemplified above, palladium nitrate, palladium sulfate,
Palladium acetate, ammonium hexachloropalladate, palladium chloride, and tetraammine palladium chloride are more preferred.

In addition to the above-mentioned Group VIII element, the catalyst
For example, in order to further improve the catalytic activity or to prevent the elution of the Group VIII element into the reaction solution at the time of the reaction, if necessary, the Periodic Table Group IB, IIB, Group III, IV
At least one element selected from the group consisting of Group V, Group V, Group VI, and Group VIIA (hereinafter, referred to as a second element group) may be further included. Specific examples of the second element group include copper, silver, gold, zinc, cadmium, mercury, thallium, tin, zinc, bismuth, arsenic, antimony, tellurium, and the like. One of these second element groups may be used alone, or two or more of them may be used in combination. Of the second group of elements, gold is particularly preferred.

Further, in addition to the above-mentioned group VIII element, the catalyst may optionally contain at least one element selected from the group consisting of alkali metals and alkaline earth metals (for example, in order to further improve the catalytic activity). Hereinafter, referred to as a third element group). Specific examples of the compound containing the third element group include potassium acetate, cesium acetate, barium acetate and the like, but are not particularly limited. As the third element group, only one kind may be used, or two or more kinds may be used in combination.

That is, the catalyst may further contain a second element group and / or a third element group as necessary in addition to the above-mentioned group VIII element. And when the catalyst contains these two or three, the group VIII element, the second element group and / or the third element group are, for example, a compound containing a group VIII element and a compound containing the second element group. And / or a compound containing a group VIII element and a second element group and / or a third element group as a composite component (composite ) May be present, or may be present in a combination of these states.

In the case where the catalyst is a carrier in which a group VIII element (and a second element group and / or a third element group) is supported on a carrier, the carrier is preferably an inorganic compound. Inorganic compounds are optimal, but are not particularly limited. As the above carrier, specifically,
For example, silicon oxide (silica), aluminum oxide (alumina), titanium oxide (titania), zirconium oxide (zirconia), magnesium oxide (magnesia), silica-alumina, silica-titania, titania-zirconia, zeolite, diatomaceous earth, etc. Examples include, but are not limited to, isocrystalline or non-crystalline metal oxides or composite oxides; clay, activated carbon; and the like. These carriers may be used alone or in combination of two or more.

When the above-mentioned Group VIII element or the like is supported on a carrier, that is, when the catalyst is a carrier having the above-mentioned carrier carrying a Group VIII element (and a second element group and / or a third element group). When, after the reaction, the catalyst and the reaction solution,
Separation is much easier. Further, the catalytic activity can be improved. In addition, the second element group and / or the third element group are not supported on a carrier, but a compound containing the second element group and / or a compound containing the third element group are supported on a carrier supporting a group VIII element. By adding to the reaction solution together with the reaction solution, the reaction solution can be used.

The method for preparing the above catalyst is not particularly limited, but the catalyst is, for example, a carrier having a carrier carrying a group VIII element (and a second element group and / or a third element group). The method of preparing the case is described below.

The method for supporting the above-mentioned Group VIII element on a carrier is not particularly limited, and examples thereof include an impregnation method, a precipitation method, an ion exchange method, a deposition method, a vapor deposition method, a precipitation method, and a coprecipitation method. Various known methods of carrying can be employed. Among the above-mentioned supporting methods, a precipitation method, a vapor deposition method, a precipitation method, a coprecipitation method and the like are more preferable. When these supporting methods are adopted, the group VIII element is supported on the carrier in the form of fine particles, so that the number of active sites of the catalyst is further increased,
The catalytic activity is further improved.

An example of a specific method for preparing a catalyst containing palladium as a group VIII element and gold as a second element group by employing a precipitation method is described below. First, a water-soluble palladium compound and a gold compound are dissolved in water. At this time, heating may be performed if necessary. Also,
If necessary, the pH of the aqueous solution may be appropriately adjusted by adding an alkali compound so that the palladium hydroxide and the gold hydroxide can precipitate and precipitate in the form of fine particles. Next, after the carrier is added to the above aqueous solution, the solution is allowed to stand for a predetermined time if necessary. Thereafter, the carrier (the carrier carrying palladium hydroxide and gold hydroxide) is taken out, washed and dried. Further, if necessary, the support is fired at a predetermined temperature. Thereby, a catalyst is prepared. The order in which palladium and gold are supported on the carrier is not particularly limited, and both may be supported simultaneously, or one of the two may be supported first and then the other.

When the catalyst is a carrier, the content of the Group VIII element depends on the desired composition of the catalyst, the combination with the second element group and / or the third element group used as required, and the like. The amount may be appropriately set, but is preferably in the range of 0.01% by weight to 20% by weight, more preferably in the range of 0.1% by weight to 5% by weight, based on the total weight of the catalyst. When the content of the group VIII element is less than the above range, the catalytic activity becomes poor, which is not preferable. On the other hand, when the content is more than the above range, the production cost of the catalyst is increased, so that it is impossible to produce (acyloxyalkyl) aromatic carboxylic acids industrially efficiently and inexpensively.

In the case where the catalyst is a carrier, the content of the second element group used as necessary may be appropriately set according to the desired composition of the catalyst, the combination with the group VIII element and the like. Although not particularly limited, for example, when the second element group is gold, it is more preferably in the range of 0.01% by weight to 20% by weight based on the total weight of the catalyst, and 1% by weight. More preferably, it is in the range of 10 to 10% by weight. When the content of gold, that is, the content of the second element group is smaller than the above range, the effect obtained by including the second element group may be poor. Specifically, the reaction rate becomes slow, the amount of the reaction intermediate produced increases, and there is a possibility that the (acyloxyalkyl) aromatic carboxylic acid as the target product may not be obtained efficiently. On the other hand, when the content is more than the above range, the production cost of the catalyst is increased, so that it may not be possible to produce (acyloxyalkyl) aromatic carboxylic acids at low cost.

In the case where the catalyst is a carrier, the content of the third element group used as necessary may be appropriately set according to the desired composition of the catalyst, the combination with the group VIII element and the like. Is not particularly limited, but may be 0.0
001% by weight to 10% by weight is more preferable,
More preferably, it is in the range of 0.001% by weight to 2% by weight. When the content of the third element group is less than the above range, the effect obtained by including the third element group may be poor.

The (acyloxyalkyl) aromatic carboxylic acids are obtained by subjecting the alkyl-substituted aromatic compounds and carboxylic acids to an oxidation reaction in the presence of the above catalyst. The oxidation reaction is performed using oxygen gas (molecular oxygen).
In the liquid or gas phase in the presence of The oxygen gas may be diluted with an inert gas such as a nitrogen gas, a helium gas, an argon gas, and a carbon dioxide gas. Also,
Air can also be used as oxygen gas. The method for supplying oxygen gas to the reaction system is not particularly limited.

The form of the oxidation reaction can be a continuous type, a batch type,
It may be any of a semi-batch type, and is not particularly limited. The catalyst may be charged together with the raw materials into the reactor when the reaction mode is, for example, a batch type, and may be previously charged into the reactor when the reaction mode is, for example, a continuous type. Alternatively, it may be charged continuously to the reactor together with the raw materials. Therefore, the catalyst may be used in any form of fixed bed, fluidized bed and suspension bed.

The amount of the catalyst to be used with respect to the alkyl-substituted aromatic compound may be set according to the type and combination of the alkyl-substituted aromatic compound and the carboxylic acid, the composition of the catalyst, the reaction conditions, and the like. is not.

The reaction conditions such as reaction temperature, reaction pressure and reaction time may be set according to the kind and combination of the alkyl-substituted aromatic compound and carboxylic acid, the composition of the catalyst and the like, and are not particularly limited. However, the reaction temperature is 80
It is preferable that the temperature is in the range of from 200C to 200C. Reaction temperature is 80 ° C
If it is less than 1, the reaction rate becomes too slow, and the oxidation reaction may not be efficiently performed. On the other hand, when the reaction temperature exceeds 200 ° C., a combustion reaction or an excessive oxidation reaction (for example, formation of dicarboxylic acids).
And the like, a side reaction such as this may easily occur, so that the oxidation reaction may not be efficiently performed. In addition, there is a possibility that carboxylic acids may cause corrosion of the reactor.

The reaction pressure may be either normal pressure (atmospheric pressure) or pressurization. However, when oxygen gas (oxygen gas not diluted with an inert gas) is used for the oxidation reaction, normal pressure (atmospheric pressure) may be used. It is preferably in the range of ４4.9 × 10 ⁶ Pa (gauge pressure). When air is used for the oxidation reaction, the pressure is in the range of normal pressure to 9.8 × Pa.
A pressure within a range of 10 ⁶ Pa (gauge pressure) is preferable. 9.8
A pressure exceeding × 10 ⁶ Pa requires a reaction facility or the like that can withstand high pressure, and is not preferable from an industrial viewpoint.

In the oxidation reaction, when the alkyl-substituted aromatic compound and / or carboxylic acid is in a liquid state under the above reaction conditions, it is not necessary to use a solvent, but the two cannot be mixed uniformly. In cases such as when the oxidation reaction is severe, the reaction solution can be diluted with a solvent inert to the reaction.

By performing the above oxidation reaction, a reaction solution containing (acyloxyalkyl) aromatic carboxylic acids is obtained. In the reaction solution, in addition to the (acyloxyalkyl) aromatic carboxylic acids as the target substance, unreacted alkyl-substituted aromatic compounds and carboxylic acids, catalysts, reaction intermediates, solvents (if used), etc. It is included.

The catalyst can be easily separated, for example, by filtering the reaction solution. When the catalyst activity is reduced (deteriorated) due to, for example, attachment of an organic substance or the like to the separated / recovered catalyst, for example, the catalyst can be easily washed with a solvent or recalcined, for example. It can be regenerated (reactivated). The separated / recovered catalyst or the regenerated catalyst can be reused in the oxidation reaction. The catalyst separation method and the regeneration method can employ various known methods, and are not particularly limited.

The (acyloxyalkyl) aromatic carboxylic acids can be prepared, for example, by distilling the reaction solution from which the catalyst has been separated, or by crystallizing using a solvent in which the (acyloxyalkyl) aromatic carboxylic acids are insoluble. It can be easily isolated. The isolated (acyloxyalkyl) aromatic carboxylic acids are used as a raw material in a method for producing (hydroxyalkyl) cycloaliphatic carboxylic acids. In addition, the isolation method of an (acyloxyalkyl) aromatic carboxylic acid can employ various known methods, and is not particularly limited.

Further, unreacted alkyl-substituted aromatic compounds and carboxylic acids, reaction intermediates, or solvents (if used) are, for example, when (acyloxyalkyl) aromatic carboxylic acids are isolated. Separately
Can be recovered. The recovered unreacted substances and the like can be reused as raw materials for the oxidation reaction. As a result, (acyloxyalkyl) aromatic carboxylic acids can be produced more efficiently and inexpensively.

The (hydroxyalkyl) cycloaliphatic carboxylic acids according to the present invention include (1) (acyloxyalkyl) aromatic carboxylic acids, preferably (acyloxyalkyl) aromatic carboxylic acids synthesized by the above method. After hydrogenation (hydrogen reduction) of the aromatic ring compound group by a ring hydrogenation reaction, the resulting (acyloxyalkyl) cyclic aliphatic carboxylic acids are hydrolyzed by a hydrolysis reaction, or (2) (acyloxy (Alkyl) aromatic carboxylic acids, preferably (acyloxyalkyl) aromatic carboxylic acids synthesized by the above method are hydrolyzed by a hydrolysis reaction, and then the aromatic ring of the obtained (hydroxyalkyl) aromatic carboxylic acids is obtained. It can be obtained by hydrogenating a compound group by a ring hydrogenation reaction.

The method for hydrogenating the aromatic ring compound group of the (acyloxyalkyl) aromatic carboxylic acid is not particularly limited, and any known method may be applied. For example, the (acyloxyalkyl) aromatic carboxylic acids are used in an amount equal to or more than the equivalent of hydrogen, and the (acyloxyalkyl) aromatic carboxylic acids are reacted with hydrogen using a hydrogenation catalyst (reduction catalyst) to easily form (acyloxyalkyl). Alkyl) Aromatic compound groups of aromatic carboxylic acids can be hydrogenated (hydrogen reduced).

The hydrogen may be used in excess with respect to the (acyloxyalkyl) aromatic carboxylic acids, and specific molar ratio of hydrogen to (acyloxyalkyl) aromatic carboxylic acids, hydrogen supply method, hydrogen partial pressure, etc. Is not particularly limited.

The ring hydrogenation reaction is performed in a liquid phase or a gas phase in the presence of hydrogen gas. The hydrogen gas may be diluted with an inert gas such as a nitrogen gas, a helium gas, an argon gas, and a carbon dioxide gas.

The above-mentioned reduction catalyst is not particularly limited, but specifically, for example, a noble metal-supported catalyst in which a noble metal element such as palladium, platinum, rhodium, ruthenium, iridium or the like is supported on a carrier Noble metal oxides such as palladium oxide, platinum oxide, rhodium oxide, ruthenium oxide and iridium oxide; noble metals such as palladium black, platinum black, rhodium black and ruthenium black; and Raney such as Raney nickel, Raney cobalt, Raney ruthenium and Raney rhodium A catalyst; a base metal-supported catalyst in which a base metal element is supported on a carrier; and the like. These reduction catalysts may be used alone,
Further, two or more kinds may be used in combination.

As the above-mentioned carrier, an inorganic compound is preferred, and a porous inorganic compound is optimal, but is not particularly limited. Specific examples of the above carrier include silicon oxide (silica), aluminum oxide (alumina), titanium oxide (titania), zirconium oxide (zirconia), magnesium oxide (magnesia), silica-alumina, and silica-titania. , Titania / zirconia, zeolite, diatomaceous earth, etc., such as non-crystalline or non-crystalline metal oxides or composite oxides; clay, activated carbon; and the like, but are not particularly limited. These carriers may be used alone or in combination of two or more. When the reduction catalyst is a supported catalyst, the reduction catalyst and the reaction solution can be easily separated after the reaction.

The method for preparing the above reduction catalyst is not particularly limited. For example, as a method for supporting the noble metal element and / or the base metal element on a carrier, a conventionally known preparation method such as an impregnation method can be adopted. When the reduction catalyst is a supported catalyst (support), the content of the noble metal element and / or the base metal element and the like are determined based on (acyloxyalkyl) aromatic carboxylic acids and metal elements supported on the support. What is necessary is just to set suitably according to a kind, reaction conditions, etc., and it is not specifically limited. Further, as a method for preparing the Raney catalyst, a conventionally known preparation method can be adopted.

Reaction substrate (acyloxyalkyl)
The amount of the reduction catalyst used for the aromatic carboxylic acids may be set according to the composition of the reduction catalyst, the reaction conditions, the method of supplying hydrogen, the partial pressure of hydrogen, and the like, and is not particularly limited. The amount of the metal element to be used is 0.00001 mol% to 0.1 mol% based on the alkyl) aromatic carboxylic acids.
It is preferable to use it so as to be within the range of 1 mol%. If the amount of the reducing catalyst used for the (acyloxyalkyl) aromatic carboxylic acids is less than the above range, the catalytic activity becomes poor, which is not preferable. on the other hand,
When the amount of the reduction catalyst used for the (acyloxyalkyl) aromatic carboxylic acids is larger than the above range,
Since the production cost of the catalyst is increased, there is a possibility that the acyloxyalkyl alicyclic carboxylic acids, and consequently, the (hydroxyalkyl) cyclic aliphatic carboxylic acids as the target product may not be produced at low cost.

Incidentally, as the specific method for proceeding the ring hydrogenation reaction, various known methods can be applied, and there is no particular limitation. The form of the ring hydrogenation reaction may be any of a continuous system, a batch system, and a semi-batch system, and is not particularly limited. The reduction catalyst may be charged together with the raw materials into the reactor when the reaction mode is, for example, a batch type, and may be previously charged into the reactor when the reaction mode is, for example, a continuous type. Or it may be charged continuously to the reactor together with the raw materials. Therefore, the catalyst may be used in any form of fixed bed, fluidized bed and suspension bed.

The reaction conditions such as the reaction temperature, reaction pressure, reaction time, etc. can be set according to the type of (acyloxyalkyl) aromatic carboxylic acid, the type of reduction catalyst, the method of supplying hydrogen, the partial pressure of hydrogen, and the like. Although not particularly limited, the reaction temperature is generally preferably from room temperature to 250 ° C, and more preferably from 50 ° C to 200 ° C. When the reaction temperature is lower than normal temperature (25 ° C.), the reaction rate becomes extremely slow, and the ring hydrogenation reaction may not be efficiently performed. On the other hand, when the reaction temperature exceeds 250 ° C., a side reaction is likely to occur, and the ring hydrogenation reaction may not be efficiently performed. The reaction pressure may be normal pressure (atmospheric pressure) or pressurization, and is not particularly limited.
内 24.5 MPa (gauge pressure) is preferable,
A range of 0.098 MPa to 14.7 MPa (gauge pressure) is more preferable. However, if the reaction pressure is high, a reaction facility or the like that can withstand high pressure is required. From an industrial viewpoint, it is more preferable to suppress the reaction pressure to 9.8 MPa (gauge pressure) or less.

In the above ring hydrogenation reaction, when the (acyloxyalkyl) aromatic carboxylic acid is in a liquid state under the above reaction conditions, it is not necessary to use a solvent.
Depending on the reaction conditions and reaction system, for example, when the ring hydrogenation reaction is intense, the reaction solution can be diluted with a solvent inert to the reaction, if necessary. For example, (acyloxyalkyl) aromatic carboxylic acids,
After mixing with an appropriate amount of a solvent, a reduction catalyst is added, the inside of the system is replaced with an inert gas, hydrogen gas is introduced, and if necessary, the ring hydrogenation reaction can be easily performed by heating. Let it proceed.

The solvent is not particularly limited, but specific examples thereof include water; methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec- Alcohols having 1 to 6 carbon atoms such as butyl alcohol and tert-butyl alcohol; ethers such as isopropyl ether, tetrahydrofuran and dioxane; saturated hydrocarbon compounds having 1 to 6 carbon atoms such as pentane, hexane and cyclohexane; No. These solvents may be used alone or in combination of two or more.

By carrying out the above-mentioned ring hydrogenation reaction, (acyloxyalkyl) cycloaliphatic carboxylic acids which are precursors (intermediates for production) of the (hydroxyalkyl) cycloaliphatic carboxylic acids according to the present invention are contained. A reaction solution is obtained. The reaction solution contains, in addition to the above (hydroxyalkyl) cycloaliphatic carboxylic acids, unreacted (acyloxyalkyl) aromatic carboxylic acids and the above reduction catalyst, or a solvent (if used). I have.

The above reduction catalyst can be easily separated, for example, by filtering the reaction solution. If the catalytic activity of the separated and recovered reduction catalyst is reduced (deteriorated) due to, for example, attachment of an organic substance or the like, for example, by washing the reduction catalyst with a solvent or recalcining, It can be easily regenerated (reactivated). Separation
The recovered reduction catalyst and the regenerated reduction catalyst can be reused for the above-mentioned ring hydrogenation reaction. The method for separating and regenerating the reduction catalyst may be any of various known methods, and is not particularly limited.

The (acyloxyalkyl) cyclic aliphatic carboxylic acids can be easily isolated, for example, by distilling or crystallizing the reaction solution from which the reduction catalyst has been separated. Further, the (acyloxyalkyl) cyclic aliphatic carboxylic acids may be purified, if necessary, after isolation. In addition, the isolation method and the purification method of the (acyloxyalkyl) cyclic aliphatic carboxylic acids can employ various known methods, and are not particularly limited.

The unreacted (acyloxyalkyl) aromatic carboxylic acids or the solvent (if used) are also separated, for example, when isolating the (acyloxyalkyl) cycloaliphatic carboxylic acids.・ Can be collected. The recovered unreacted substances and the like can be reused as a raw material for the ring hydrogenation reaction. This allows
(Acyloxyalkyl) cycloaliphatic carboxylic acids, and thus (hydroxyalkyl) cycloaliphatic carboxylic acids, can be produced more efficiently and inexpensively. The method for separating and recovering these (acyloxyalkyl) aromatic carboxylic acids and the solvent (if used) is not particularly limited.

The (hydroxyalkyl) cycloaliphatic carboxylic acids according to the present invention can be easily obtained by hydrolyzing the (acyloxyalkyl) cycloaliphatic carboxylic acids which are precursors thereof.

The (acyloxyalkyl) cycloaliphatic carboxylic acids used in the above reaction include a divalent or higher valent alicyclic compound group having 6 or more carbon atoms and a substituent such as an acyloxyalkyl group and a carboxyl group in the same molecule. The compound is not particularly limited as long as it has the following general formula (1): R ⁶ COO—CR ¹ R ² —Z—COOH (1) Z represents a divalent or higher valent alicyclic compound group having 6 or more carbon atoms, R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms. It represents group, or -OCOR ⁵ groups, R ⁵ is from 1 to 4 carbon atoms
Wherein R ⁶ is a substituted carbon number of 1 to
6 alkyl groups, C1-6 alkene groups, C1
Alkyne group or substituted benzene).

A divalent or higher alicyclic compound group having 6 or more carbon atoms means an alicyclic compound having 6 or more carbon atoms, that is, an alicyclic compound having a 6-membered or more multi-membered ring and a hydrogen atom derived therefrom. Represents a divalent or higher valent group obtained by removing two or more groups, and more specifically,
A hydride (hydroaromatic compound group) of the aromatic ring compound group is shown, and in the present invention, a divalent or higher valent carbocyclic aromatic compound group (monocyclic or condensed polycyclic aromatic compound group) or A group having a structure obtained by hydrogenating a heteroaromatic compound group having a valency of at least one (monocyclic or condensed polycyclic heteroaromatic compound group) (monocyclic or condensed polycyclic aliphatic compound group, Cyclic or fused polycyclic aliphatic heterocyclic compound group). More specifically, it indicates a group having a structure obtained by hydrogenating a condensed ring such as a benzene ring or a naphthalene ring from which two or more hydrogen atoms have been removed, or a heterocyclic ring such as a pyridine ring.

As the group having such a structure, two or more hydrogen atoms are removed from cycloalkanes having 6 or more carbon atoms and derivatives thereof (including condensed polycyclic compounds) such as cyclohexane, tetralin and decalin. Or a divalent or higher valent group, a piperidine ring, or other 6-membered heterocyclic compound (monocyclic or condensed polycyclic aliphatic heterocyclic compound) in which two or more hydrogen atoms have been removed. And a group having a valency or higher. Further, the (acyloxyalkyl) cyclic aliphatic carboxylic acids may have a functional group that is inactive to a hydrolysis reaction described below.

As the (acyloxyalkyl) cyclic aliphatic carboxylic acids, specifically, for example, 2-, 3
Examples thereof include acyloxyalkylcyclohexanecarboxylic acids such as-, 4-acetoxymethylcyclohexanecarboxylic acid, but are not particularly limited.

The method for hydrolyzing the (acyloxyalkyl) cyclic aliphatic carboxylic acids is not particularly limited, and any known method may be employed. The hydrolysis can be easily performed by, for example, a method using an aqueous solution containing the (acyloxyalkyl) cyclic aliphatic carboxylic acid and an equivalent or more of an alkali compound, or a method using an acid catalyst.

For example, in the method using an acid catalyst, an (acyloxyalkyl) cyclic aliphatic carboxylic acid and an appropriate amount of water are mixed, and then an acid catalyst is added to the reaction system, and if necessary, heated. By doing so, the hydrolysis reaction can easily proceed.

Specific examples of the acid catalyst include a homogeneous catalyst such as sulfuric acid, hydrochloric acid, nitric acid, heteropolyacid, and p-toluenesulfonic acid; and a heterogeneous catalyst such as an acidic ion exchange resin, zeolite and clay. A catalyst (solid acid catalyst); however, the catalyst is not particularly limited. The amount of the acid catalyst used for the (acyloxyalkyl) cyclic aliphatic carboxylic acids is not particularly limited.

The reaction conditions such as reaction temperature, reaction pressure and reaction time may be set according to the kind of the (acyloxyalkyl) cyclic aliphatic carboxylic acid, the kind of the alkali compound or the acid catalyst, and are particularly limited. Although it is not intended, the reaction temperature is preferably in the range of 30 ° C to 160 ° C,
C. to 140.degree. C. is more preferable. Reaction temperature 3
If the temperature is lower than 0 ° C., the reaction rate may be too slow, and the hydrolysis reaction may not be efficiently performed. On the other hand, when the reaction temperature exceeds 160 ° C., a by-product such as a polymerization product is easily generated by a side reaction such as a polymerization reaction, so that the hydrolysis reaction may not be efficiently performed. is there. The reaction pressure may be any one of reduced pressure, normal pressure (atmospheric pressure), and pressurized, but normal pressure to 3.
A range of 9 × 10 ⁵ Pa (gauge pressure) is preferable.

By performing the above hydrolysis reaction, an aqueous solution containing (hydroxyalkyl) cyclic aliphatic carboxylic acids is obtained. In the aqueous solution, in addition to the (hydroxyalkyl) cycloaliphatic carboxylic acids that are the target product, the (acyloxyalkyl) cycloaliphatic carboxylic acids that are unreacted and the (acyloxyalkyl) cycloaliphatic A carboxylic acid such as a monocarboxylic acid, which is by-produced when obtaining a (hydroxyalkyl) cyclic aliphatic carboxylic acid from a carboxylic acid, and a catalyst depending on the reaction method are contained.

The above catalyst can be easily separated, for example, by filtering the reaction solution. When the catalyst activity is reduced (deteriorated) due to, for example, attachment of an organic substance or the like to the separated / recovered catalyst, for example, the catalyst can be easily washed with a solvent or recalcined, for example. It can be regenerated (reactivated). Separated and recovered,
A catalyst such as an acid catalyst (hydrolysis catalyst) and a regenerated catalyst such as an acid catalyst (hydrolysis catalyst) can be reused in the hydrolysis reaction. The method for separating the catalyst and the method for regenerating the catalyst can employ various known methods, and are not particularly limited.

(Hydroxyalkyl) cyclic aliphatic carboxylic acids can be easily isolated, for example, by distilling or crystallizing the aqueous solution from which the catalyst has been removed. The (hydroxyalkyl) cyclic aliphatic carboxylic acids may be purified as necessary after isolation.
In addition, the isolation | separation method and the refinement | purification method of a (hydroxyalkyl) cyclic aliphatic carboxylic acid can employ | adopt various well-known methods, and it does not specifically limit. According to the above method, (hydroxyalkyl) cycloaliphatic carboxylic acids can be obtained in a higher yield than before by a very easy method of hydrolysis of (acyloxyalkyl) cycloaliphatic carboxylic acids. .

The (acyloxyalkyl) cycloaliphatic carboxylic acids which are unreacted products and the (hydroxyalkyl) cycloaliphatic carboxylic acids obtained from the (acyloxyalkyl) cycloaliphatic carboxylic acids described above are not reacted. The resulting carboxylic acids such as monocarboxylic acids are, for example,
When isolating (hydroxyalkyl) cycloaliphatic carboxylic acids, they can be separated and recovered together.

The recovered unreacted product, that is, the (acyloxyalkyl) cycloaliphatic carboxylic acid is purified if necessary, and then subjected to a hydrolysis reaction again to obtain a (hydroxyalkyl) cycloaliphatic aliphatic carboxylic acid. Carboxylic acids can be obtained. That is, it can be reused as a raw material for the hydrolysis reaction. Incidentally, these (acyloxyalkyl) cyclic aliphatic carboxylic acids, and monocarboxylic acids and the like by-produced in obtaining (hydroxyalkyl) cyclic aliphatic carboxylic acids from the (acyloxyalkyl) cyclic aliphatic carboxylic acids described above. The method for separating and recovering the carboxylic acids is not particularly limited.

Further, the carboxylic acids by-produced in obtaining the (hydroxyalkyl) aromatic carboxylic acids from the (acyloxyalkyl) cycloaliphatic carboxylic acids are separated and recovered, and, if necessary, purified. As a raw material of an acyloxyalkyl) aromatic carboxylic acid, it can be reused in the above-mentioned reaction (oxidative esterification reaction) between the alkyl-substituted aromatic compound and a carboxylic acid.
Thereby, (hydroxyalkyl) cycloaliphatic carboxylic acids can be produced more efficiently and inexpensively.

Next, a method for producing (hydroxyalkyl) cycloaliphatic carboxylic acids from (acyloxyalkyl) aromatic carboxylic acids via (hydroxyalkyl) aromatic carboxylic acids, ie, the method of the above (2) Will be described below.

The (hydroxyalkyl) aromatic carboxylic acids can be easily obtained by hydrolyzing the (acyloxyalkyl) aromatic carboxylic acids.
The hydrolysis reaction can easily proceed, for example, by using an aqueous solution containing the (acyloxyalkyl) aromatic carboxylic acid and an equivalent or more of an alkali compound, or by using an acid catalyst. It should be noted that a specific method for promoting the hydrolysis reaction can employ various known methods, and is not particularly limited. For example, the above hydrolysis reaction can be advanced by employing the same method as the hydrolysis of the (acyloxyalkyl) cyclic aliphatic carboxylic acid. For example, in the method using an acid catalyst, after mixing an (acyloxyalkyl) aromatic carboxylic acid and an appropriate amount of water, an acid catalyst is added to the reaction system, and the mixture is heated if necessary. The hydrolysis reaction can easily proceed. In this case, the reaction conditions for the hydrolysis of the (acyloxyalkyl) aromatic carboxylic acids may be the same as those for the hydrolysis reaction of the (acyloxyalkyl) cycloaliphatic carboxylic acid, but are particularly limited. Not something.

By performing the above hydrolysis reaction, an aqueous solution containing (hydroxyalkyl) aromatic carboxylic acids is obtained. The aqueous solution contains, in addition to the (hydroxyalkyl) aromatic carboxylic acids, unreacted (acyloxyalkyl) aromatic carboxylic acids and the above (acyloxyalkyl) aromatic carboxylic acids to (hydroxyalkyl) aromatic carboxylic acids. Carboxylic acids such as monocarboxylic acids, which are by-produced in obtaining the acids, and a catalyst such as an acid catalyst depending on the reaction method are contained.

The above catalyst can be easily separated, for example, by filtering the reaction solution. When the catalyst activity is reduced (deteriorated) due to, for example, attachment of an organic substance or the like to the separated / recovered catalyst, for example, the catalyst can be easily washed with a solvent or recalcined, for example. It can be regenerated (reactivated). Separated and recovered,
A catalyst such as an acid catalyst (hydrolysis catalyst) or a regenerated catalyst such as an acid catalyst (hydrolysis catalyst) can be reused in the hydrolysis reaction. The method for separating the catalyst and the method for regenerating the catalyst can employ various known methods, and are not particularly limited.

(Hydroxyalkyl) aromatic carboxylic acids can be easily isolated, for example, by distilling or crystallizing the aqueous solution from which the catalyst has been removed. The (hydroxyalkyl) aromatic carboxylic acids may be purified as necessary after isolation. still,
Various known methods can be employed for isolating and purifying (hydroxyalkyl) aromatic carboxylic acids, and are not particularly limited.

Further, unreacted (acyloxyalkyl) aromatic carboxylic acids and monocarboxylic acids produced as by-products when the (hydroxyalkyl) aromatic carboxylic acids are obtained from the (acyloxyalkyl) aromatic carboxylic acids. For example, when isolating (hydroxyalkyl) aromatic carboxylic acids, they can be separated and recovered together.

The recovered unreacted product, that is, the (acyloxyalkyl) aromatic carboxylic acid is purified if necessary, and then subjected to a hydrolysis reaction again.
(Hydroxyalkyl) aromatic carboxylic acids can be obtained. That is, it can be reused as a raw material for the hydrolysis reaction. Separation and separation of these (acyloxyalkyl) aromatic carboxylic acids and carboxylic acids such as monocarboxylic acids by-produced when obtaining (hydroxyalkyl) aromatic carboxylic acids from the (acyloxyalkyl) aromatic carboxylic acids. The recovery method is not particularly limited.

Further, the carboxylic acids by-produced in obtaining the (hydroxyalkyl) aromatic carboxylic acids from the (acyloxyalkyl) aromatic carboxylic acids are separated and separated.
After being collected and, if necessary, purified, the (acyloxyalkyl) aromatic carboxylic acid can be reused as a raw material for the above-mentioned reaction between the alkyl-substituted aromatic compound and the carboxylic acid (oxidative esterification reaction). it can.

As a result, (hydroxyalkyl) aromatic carboxylic acids, and furthermore, (hydroxyalkyl) cycloaliphatic carboxylic acids can be produced more efficiently and inexpensively.

According to the above method, a precursor (intermediate for production) of a (hydroxyalkyl) cyclic aliphatic carboxylic acid
(Hydroxyalkyl) aromatic carboxylic acids
It can be obtained in a high yield by a very easy method called hydrolysis. Therefore, the (hydroxyalkyl) aromatic carboxylic acids can be produced industrially, efficiently and at low cost.

The (hydroxyalkyl) aromatic carboxylic acids are not particularly limited, but specifically, for example, HO—CR ¹ R ² —Ar—COOH (4) ) (wherein, Ar represents a divalent or more aromatic ring compound group, R ¹
Represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms,
R ² is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or -
OCOR ⁵ group, and R ⁵ represents an alkyl group having 1 to 4 carbon atoms).

As the (hydroxyalkyl) aromatic carboxylic acids, more specifically, for example, o-, m-,
o-, m-, p- such as p-hydroxymethylbenzoic acids
And hydroxyalkyl benzoic acids.

(Hydroxyalkyl) cyclic aliphatic carboxylic acids can be easily obtained by hydrogenating (hydrogen reduction) the aromatic ring compound group of the (hydroxyalkyl) aromatic carboxylic acids by a ring hydrogenation reaction. .

The method for hydrogenating the aromatic ring compound group of the (hydroxyalkyl) aromatic carboxylic acid is not particularly limited. For example, a method in which hydrogen is used in an amount equivalent to or more than the (hydroxyalkyl) aromatic carboxylic acid is used. Then, the (hydroxyalkyl) aromatic carboxylic acids are reacted with hydrogen (hydrogen reduction) using a hydrogenation catalyst (reduction catalyst), so that the reaction can easily proceed.

Hydrogen may be used in excess with respect to the (hydroxyalkyl) aromatic carboxylic acids, such as the specific molar ratio of hydrogen to the (hydroxyalkyl) aromatic carboxylic acids, the method of supplying hydrogen, the hydrogen partial pressure, and the like. Is not particularly limited.

The ring hydrogenation reaction is performed in a liquid phase or a gas phase in the presence of hydrogen gas. The hydrogen gas may be diluted with an inert gas such as a nitrogen gas, a helium gas, an argon gas, and a carbon dioxide gas.

The reduction catalyst is not particularly limited, but a catalyst containing at least one noble metal element selected from rhodium and ruthenium is preferably used. Specifically, for example, a supported catalyst in which at least one selected from rhodium and ruthenium is supported on a carrier; oxides such as rhodium oxide and ruthenium oxide;
Simple metals such as rhodium black and ruthenium black;
Raney catalysts such as Raney rhodium and Raney ruthenium; and the like. Among them, a supported catalyst having excellent catalytic activity and capable of easily separating the reduction catalyst and the reaction solution after the reaction is particularly preferable. These reduction catalysts may be used alone or in combination of two or more.

As the above-mentioned carrier, an inorganic compound is suitable, and a porous inorganic compound is most suitable, but it is not particularly limited. Specific examples of the above carrier include silicon oxide (silica), aluminum oxide (alumina), titanium oxide (titania), zirconium oxide (zirconia), magnesium oxide (magnesia), silica-alumina, and silica-titania. , Titania / zirconia, zeolite, diatomaceous earth, etc., such as non-crystalline or non-crystalline metal oxides or composite oxides; clay, activated carbon; and the like, but are not particularly limited. These carriers may be used alone or in combination of two or more.

The amount of the reduction catalyst to be used for the (hydroxyalkyl) aromatic carboxylic acid as the reaction substrate may be set according to the composition of the reduction catalyst, the reaction conditions, the method of supplying hydrogen, the partial pressure of hydrogen, and the like. Although not particularly limited, it is preferable to use the metal element so that the content of the metal element with respect to the (hydroxyalkyl) aromatic carboxylic acid is in the range of 0.00001 mol% to 0.1 mol%. If the amount of the reducing catalyst used for the (hydroxyalkyl) aromatic carboxylic acids is less than the above range, the catalytic activity becomes poor, which is not preferable. On the other hand, when the amount of the reduction catalyst used for the (hydroxyalkyl) aromatic carboxylic acids is larger than the above range, the production cost of the catalyst increases, so that the (hydroxyalkyl) cycloaliphatic carboxylic acids as the target product cannot be used. , It may not be possible to manufacture it at low cost.

It is to be noted that a specific method for proceeding the ring hydrogenation reaction is not particularly limited, and various known methods can be applied. More specifically, for example, the hydrogenation of the aromatic ring compound group of the (hydroxyalkyl) aromatic carboxylic acid is performed by employing the same method as the hydrogenation of the aromatic ring compound group of the (acyloxyalkyl) aromatic carboxylic acid. Can be implemented. The form of the ring hydrogenation reaction may be any of a continuous system, a batch system, and a semi-batch system.
There is no particular limitation. The reduction catalyst may be charged together with the raw materials into the reactor when the reaction mode is, for example, a batch type, and may be previously charged into the reactor when the reaction mode is, for example, a continuous type. Or it may be charged continuously to the reactor together with the raw materials. Therefore, the catalyst may be used in any form of fixed bed, fluidized bed and suspension bed.

The reaction conditions such as the reaction temperature, the reaction pressure, and the reaction time may be set according to the type of the (hydroxyalkyl) aromatic carboxylic acid, the type of the reduction catalyst, the method of supplying hydrogen, the partial pressure of hydrogen, and the like. Although not particularly limited, the reaction temperature is generally preferably from room temperature to 250 ° C, and more preferably from 50 ° C to 200 ° C. When the reaction temperature is lower than normal temperature (25 ° C.), the reaction rate becomes extremely slow, and the ring hydrogenation reaction may not be efficiently performed. On the other hand, when the reaction temperature exceeds 250 ° C., a side reaction is likely to occur, and the ring hydrogenation reaction may not be efficiently performed. The reaction pressure may be normal pressure (atmospheric pressure) or pressurization, and is not particularly limited.
内 24.5 MPa is preferable, and 0.098 M
The range of Pa to 14.7 MPa is more preferable. However, if the reaction pressure is high, a reaction facility or the like that can withstand the high pressure is required.
It is even more preferable to suppress the pressure to 8 MPa (gauge pressure) or less.

In the above-mentioned ring hydrogenation reaction, when the (hydroxyalkyl) aromatic carboxylic acid is in a liquid state under the above-mentioned reaction conditions, it is not necessary to use a solvent, but depending on the reaction conditions and reaction system, for example, When the ring hydrogenation reaction is severe, the reaction solution can be diluted with a solvent inert to the reaction, if necessary. For example,
After mixing (hydroxyalkyl) aromatic carboxylic acids and an appropriate amount of solvent, a reducing catalyst is added, the inside of the system is replaced with an inert gas, hydrogen gas is introduced, and if necessary, heating is performed. This allows the ring hydrogenation reaction to proceed easily. Such a solvent is not particularly limited, and the same solvents as those exemplified in the ring hydrogenation reaction of the (acyloxyalkyl) aromatic carboxylic acid can be used.

The conditions for carrying out the ring hydrogenation reaction using the above-mentioned reduction catalyst are as follows: (Hydroxyalkyl) is determined using a reduction catalyst conventionally used in the ring hydrogenation reaction of (hydroxyalkyl) aromatic carboxylic acids. The reaction temperature and reaction pressure are reduced as compared with the conditions for performing the ring hydrogenation reaction of aromatic carboxylic acids, and the desired product (hydroxyalkyl)
Cycloaliphatic carboxylic acids can be produced industrially, efficiently and inexpensively.

Incidentally, a specific method for proceeding the ring hydrogenation reaction can employ various known methods, and is not particularly limited. Although the reaction conditions are inferior to the above-mentioned method, examples of the reduction catalyst in the ring hydrogenation reaction of (hydroxyalkyl) aromatic carboxylic acids include the ring hydrogenation reaction of (hydroxyalkyl) aromatic carboxylic acids. The hydrogen reduction can also be carried out by using a conventionally known technique using a catalyst other than the catalyst containing at least one element selected from rhodium and ruthenium.

By carrying out the above-mentioned ring hydrogenation reaction, a reaction solution containing the (hydroxyalkyl) cyclic aliphatic carboxylic acid as the target product is obtained. The reaction solution contains, in addition to the (hydroxyalkyl) cycloaliphatic carboxylic acid as the target substance, the (hydroxyalkyl) aromatic carboxylic acid as the unreacted substance and the above reduction catalyst, or a solvent (if used). include.

The reduction catalyst can be easily separated, for example, by filtering the reaction solution. If the catalytic activity of the separated and recovered reduction catalyst is reduced (deteriorated) due to, for example, attachment of an organic substance or the like, for example, by washing the reduction catalyst with a solvent or recalcining, It can be easily regenerated (reactivated). Separation
The recovered reduction catalyst and the regenerated reduction catalyst can be reused for the above-mentioned ring hydrogenation reaction. The method for separating and regenerating the reduction catalyst may be any of various known methods, and is not particularly limited.

(Hydroxyalkyl) cyclic aliphatic carboxylic acids can be easily isolated, for example, by distilling or crystallizing the reaction solution from which the reduction catalyst has been separated. The (hydroxyalkyl) cyclic aliphatic carboxylic acids may be purified as necessary after isolation. In addition, the isolation | separation method and purification method of a (hydroxyalkyl) cyclic aliphatic carboxylic acid can employ | adopt various well-known methods, and it does not specifically limit.

Further, the unreacted (hydroxyalkyl) aromatic carboxylic acids or the solvent (if used) are also separated when, for example, isolating the (hydroxyalkyl) cyclic aliphatic carboxylic acids.・ Can be collected. The recovered unreacted substances and the like can be reused as a raw material for the ring hydrogenation reaction. This allows
(Hydroxyalkyl) cycloaliphatic carboxylic acids can be produced more efficiently and inexpensively. still,
The method for separating and recovering these (hydroxyalkyl) aromatic carboxylic acids and the solvent (if used) is not particularly limited.

According to the above-mentioned production method according to the present invention,
Starting from (acyloxyalkyl) aromatic carboxylic acids, a (hydroalkyl) cycloaliphatic carboxylic acid such as hydroxyalkylcyclohexanecarboxylic acid can be produced at a high conversion and a high yield by a ring hydrogenation reaction and a hydrolysis reaction. It can be manufactured industrially efficiently and at low cost.

(Hydroxyalkyl) cycloaliphatic carboxylic acids produced by the production method according to the present invention include a divalent or higher valent alicyclic compound group having 6 or more carbon atoms and a substituent such as a hydroxyalkyl group and a carboxyl group. A compound having a group within the same molecule, and is not particularly limited. For example, specifically, for example, a compound represented by the following general formula (5): HO—CR ¹ R ² —Z—COOH (5) Wherein Z represents a divalent or higher valent alicyclic compound group having 6 or more carbon atoms, R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² represents a hydrogen atom, 1 to 3 carbon atoms. Represents an alkyl group or —OCOR ⁵ group, wherein R ⁵ has 1 to 4 carbon atoms.
Which represents an alkyl group).

The divalent or higher valent alicyclic compound group having 6 or more carbon atoms means an alicyclic compound having 6 or more carbon atoms, that is, an alicyclic compound having a 6 or more-membered multi-membered ring and a hydrogen atom derived therefrom. Represents a divalent or higher valent group obtained by removing two or more groups, and more specifically,
A hydride (hydroaromatic compound group) of the aromatic ring compound group is shown, and in the present invention, a divalent or higher valent carbocyclic aromatic compound group (monocyclic or condensed polycyclic aromatic compound group) or A group having a structure obtained by hydrogenating a heteroaromatic compound group having a valency of at least one (monocyclic or condensed polycyclic heteroaromatic compound group) (monocyclic or condensed polycyclic aliphatic compound group, Cyclic or fused polycyclic aliphatic heterocyclic compound group). More specifically, it indicates a group having a structure obtained by hydrogenating a condensed ring such as a benzene ring or a naphthalene ring from which two or more hydrogen atoms have been removed, or a heterocyclic ring such as a pyridine ring.

As the group having such a structure, two or more hydrogen atoms are removed from cycloalkanes having 6 or more carbon atoms and derivatives thereof (including condensed polycyclic compounds) such as cyclohexane, tetralin and decalin. Or a divalent or higher valent group, a piperidine ring, or other 6-membered heterocyclic compound (monocyclic or condensed polycyclic aliphatic heterocyclic compound) in which two or more hydrogen atoms have been removed. And a group having a valency or higher. Further, the (hydroxyalkyl) cyclic aliphatic carboxylic acids may have a functional group that is inactive to the above-described ring hydrogenation reaction, hydrolysis reaction, and the like.

The above-mentioned (acyloxyalkyl) aromatic carboxylic acids, which are the starting materials, are combined with the alkyl-substituted aromatic compounds and carboxylic acids in the presence of oxygen to form a periodic table VIII.
If it is produced by partial oxidation using a catalyst containing an element belonging to the group, for example, the above-mentioned hydroxyalkylcyclohexane carboxylic acid can be obtained using an inexpensive alkyl-substituted aromatic compound, such as xylene, which is industrially very easily available. (Hydroxyalkyl) cyclic aliphatic carboxylic acids such as acids can be produced industrially, efficiently and at low cost.

More specifically, when p-xylene is used as a starting material, 4-hydroxymethylcyclohexanecarboxylic acid can be produced industrially, efficiently and at low cost.

That is, in the method for producing the (hydroxyalkyl) cyclic aliphatic carboxylic acids according to the present invention, the alkyl-substituted aromatic compound represented by the general formula (3) and the carboxylic acid are reacted with the presence of oxygen. It is preferable that the method further includes a step of producing the above (acyloxyalkyl) aromatic carboxylic acids by partially oxidizing using a catalyst containing an element belonging to Group VIII of the periodic table.

According to the above-mentioned method, for example, an inexpensive alkyl-substituted aromatic compound such as xylene is used as a starting material, which is very easily industrially available, and the alkyl-substituted aromatic compound is converted to oxygen. By reacting with a carboxylic acid such as acetic acid in the presence, a (acyloxyalkyl) aromatic carboxylic acid such as acetoxymethyl benzoic acid used as a raw material for producing a (hydroxyalkyl) cycloaliphatic carboxylic acid, It can be manufactured industrially, efficiently and inexpensively. Therefore, using an inexpensive alkyl-substituted aromatic compound such as xylene as a starting material, which is very easily industrially available, reacting the alkyl-substituted aromatic compound with a carboxylic acid such as acetic acid in the presence of oxygen. To give (acyloxyalkyl) aromatic carboxylic acids such as acetoxymethylbenzoic acid, and then from the (acyloxyalkyl) aromatic carboxylic acids via (acyloxyalkyl) cyclic aliphatic carboxylic acids such as acetoxymethylcyclohexanecarboxylic acid. To produce (hydroxyalkyl) cycloaliphatic carboxylic acids such as hydroxymethylcyclohexanecarboxylic acid, or from (acyloxyalkyl) aromatic carboxylic acids such as acetoxymethylbenzoic acid to hydroxymethylbenzoic acid or the like. Hydroxyalkyl) aromatic (Hydroxyalkyl) cycloaliphatic carboxylic acids such as hydroxymethylcyclohexanecarboxylic acid are produced via boric acids to produce (hydroxyalkyl) cycloaliphatic carboxylic acids at lower cost and industrially. be able to.

Further, when (cycloalkyl) cyclic aliphatic carboxylic acids such as hydroxymethylcyclohexanecarboxylic acid are obtained from (acyloxyalkyl) aromatic carboxylic acids such as acetoxymethylbenzoic acid, carboxylic acids such as acetic acid are by-produced. Acids can be reused for the reaction of alkyl-substituted aromatic compounds such as xylene with carboxylic acids. This makes it possible to produce (hydroxyalkyl) cyclic aliphatic carboxylic acids industrially, more efficiently and at low cost.

The hydroxyalkylcyclohexanecarboxylic acids, which are one kind of these (hydroxyalkyl) cyclic aliphatic carboxylic acids obtained by the production method according to the present invention, and their precursors (intermediates for production)
(Hydroxyalkyl) aromatic carboxylic acids and (acyloxyalkyl) cyclic aliphatic carboxylic acids, acyloxyalkylcyclohexanecarboxylic acids, which are a kind of (cycloalkyl) carboxylic acids, and (acyloxyalkyl) aromatic carboxylic acids used as raw materials are all synthesized. It is an industrially extremely useful compound as a raw material for producing fibers, synthetic resins (particularly, heat-resistant polymers), plasticizers and the like, for example, a homopolyester and a raw material for producing a copolyester with ethylene glycol and the like. .

[0125]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited thereto. First, a production example of p-acetoxymethylbenzoic acid as an (acyloxyalkyl) aromatic carboxylic acid used as a raw material in the following examples is shown below.

[Production Example 1] 0.22 g of tetrachloroauric acid (III) tetrahydrate as a compound containing the second element group was dissolved in 200 ml of water, heated to 60 ° C and then sodium hydroxide. The pH was adjusted to 8.5 using an aqueous solution. Next, 0.062 g of tetraammine palladium dichloride as a compound containing a Group VIII element was added to and dissolved in the aqueous solution. Thus, an aqueous solution of tetrachloroauric acid-tetraamminepalladium dichloride was prepared. To the obtained aqueous solution, at 60 ° C., 5 g of titanium oxide (manufactured by Norton Co., Ltd.) was added, and the mixture was stirred at the same temperature for 1 hour to suspend the titanium oxide. The gold precipitate was immobilized.

Thereafter, the suspension was filtered, and the residue after filtration, that is, the palladium-gold-titanium immobilized product was washed with water and then washed at 120 ° C. for 8 hours.
Let dry for hours. Then, the immobilized product is placed in air for 4 hours.
By calcining at 00 ° C. for 3 hours, a palladium-gold catalyst supporting titanium oxide (hereinafter, referred to as catalyst (1)) was obtained. The supported amount (content) of palladium in the catalyst (1) was 0.5% by weight, and the supported amount (content) of gold was 2.0% by weight.

Next, the oxidation reaction of the alkyl-substituted aromatic compounds was carried out using the catalyst (1). That is, capacity 1
2.0 g of the prepared catalyst (1), 5.0 g of p-xylene as an alkyl-substituted aromatic compound (reaction substrate), and 24.0 g of acetic acid as a carboxylic acid were charged into a 00 ml rotary autoclave. 20 mg of bismuth oxide acetate, which is a compound containing the two element group, and 0.2 g of potassium acetate, which is a compound containing the third element group, were sealed. Next, the autoclave was filled with oxygen gas and the inside was pressurized to 9.8 × 10 ⁵ Pa (gauge pressure), and then the autoclave was heated to 140 ° C.
The oxidation reaction was carried out for 2.0 hours while stirring at 0 rpm.

After completion of the reaction, the autoclave was cooled.
Thereafter, the contents were taken out, the catalyst (1) was removed, and the composition of the reaction solution was analyzed using gas chromatography and liquid chromatography. As a result, 2.59 g (yield 2) of p-acetoxymethylbenzoic acid as (acyloxyalkyl) aromatic carboxylic acids was contained in the reaction solution.
8.5 mol%). In addition, in the reaction solution,
(Acyloxyalkyl) precursors of p-acetoxymethylbenzoic acid as aromatic carboxylic acids (reaction intermediates)
3.54 g of p-xylylene diacetate (yield 3
4.0 mol%), and 1.26 g of p-methylbenzyl acetate (yield 16.4 mol%).

[Production Example 2] Instead of p-xylene, p-
The oxidation reaction was carried out under the same reaction conditions as in Example 1 except that 5.0 g of xylylene diacetate (alkyl-substituted aromatic compounds) was used. After completion of the reaction, the composition of the reaction solution was analyzed using liquid chromatography. As a result, it was found that the reaction solution contained 1.95 g (yield: 44.7 mol%) of p-acetoxymethylbenzoic acid.

[Production Example 3] Instead of p-xylene, p-
The oxidation reaction was carried out under the same reaction conditions as in Example 1 except that 5.0 g of methylbenzyl acetate (alkyl-substituted aromatic compounds) was used. After completion of the reaction, the composition of the reaction solution was analyzed using gas chromatography and liquid chromatography.
2.85 g of acetoxymethyl benzoic acid (yield 48.2)
Mol%). In addition, the reaction solution includes p-xylylene glycol (p-xylene-
(α, α′-diol) 2.40 g (10.8 mol% yield).

Example 1 In an autoclave having a capacity of 100 ml, 5 g of p-acetoxymethylbenzoic acid as (acyloxyalkyl) aromatic carboxylic acids and 20 ml of water were added.
g, and 10 g of methanol, and 1.0 g of activated carbon-supported ruthenium obtained by supporting ruthenium on activated carbon was added as a reduction catalyst, followed by sealing. The supported amount (content) of ruthenium in the reduction catalyst was 5% by weight.

Next, after the inside of the autoclave was replaced with nitrogen gas, hydrogen gas was introduced into the autoclave to pressurize the inside to 4.9 × 10 ⁶ Pa (gauge pressure). afterwards,
The autoclave was heated to 100 ° C., and a ring hydrogenation reaction was performed while stirring the reaction solution in the autoclave until hydrogen absorption disappeared.

After the completion of the reaction, the reaction solution was cooled. Thereafter, the reaction solution was filtered to separate the reduction catalyst, and the composition of the reaction solution was analyzed by gas chromatography to find that the p-
The conversion of acetoxymethyl benzoic acid is 100 mol%, and the reaction solution contains, as the (acyloxyalkyl) cycloaliphatic carboxylic acids according to the present invention, the reduction product of p-acetoxymethyl benzoic acid 4 4.55 g of acetoxymethylcyclohexanecarboxylic acid (yield 88
Mol%; trans / cis mixture).

The above 4-acetoxymethylcyclohexanecarboxylic acid was identified by ¹ H-NMR and ¹³ C-NMR.
Was measured. The spectral data of the compound are shown below.

¹ H-NMR (solvent; CDCl ₃ ) Chemical shift value δ (ppm): (multiplicity, equivalent number of protons) δ: 0.8 to 2.8 (m, 9H) δ: 2.02 (s) , 3H) δ: 2.57 to 2.62 (m, 1H) δ: 3.85 to 3.92 (m, 2H) δ: 10.6 to 11.4 (b, 1H) ¹³ C-NMR ( Solvent: CDCl ₃ ) Chemical shift value δ (ppm): 20.8, 25.8, 2
7.6,28.3,35.2,36.2,41.0,4
3.9, 68.0, 68.9, 171.1, 180.
0,180.6

Example 2 2 g of 4-acoxymethylcyclohexanecarboxylic acid as the (acyloxyalkyl) cycloaliphatic carboxylic acid obtained in Example 1 and 6 g of water were placed in a 50 ml-capacity eggplant flask equipped with a reflux tube. And 26 mg of p-toluenesulfonic acid as an acid catalyst were charged all at once. Thereafter, the aqueous solution in the eggplant flask was heated to 100 ° C., and subjected to a hydrolysis reaction for 3 hours while stirring.

After the completion of the reaction, the aqueous solution was cooled. Thereafter, the aqueous solution was filtered to separate the acid catalyst, and the composition of the aqueous solution was analyzed by liquid chromatography. As a result, the conversion of 4-acetoxymethylcyclohexanecarboxylic acid was 8%.
5 mol%, and the aqueous solution contains 4-hydroxyalkyl) aliphatic carboxylic acids according to the present invention as 4-hydroxyaliphatic carboxylic acids.
It contained 1.34 g (yield: 84.8 mol%) of 4-hydroxymethylcyclohexanecarboxylic acid, which is a hydrolysis product of acetoxymethylcyclohexanecarboxylic acid.

Example 3 5 g of p-acetoxymethylbenzoic acid as an (acyloxyalkyl) aromatic carboxylic acid was placed in a 100 ml-capacity eggplant-shaped flask equipped with a reflux tube.
10 g of water and 1.85 g of sodium hydroxide as an alkali compound were charged all at once. Thereafter, the aqueous solution in the eggplant flask was heated to 100 ° C., and subjected to a hydrolysis reaction for 2 hours while stirring.

After the completion of the reaction, the aqueous solution was cooled. Thereafter, the aqueous solution was neutralized with 0.1N hydrochloric acid, and the composition of the aqueous solution was analyzed by liquid chromatography. As a result, the conversion of p-acetoxymethylbenzoic acid was 100 mol%,
The aqueous solution contains (hydroxyalkyl) according to the present invention.
As aromatic carboxylic acids, 3.91 g (yield 100 mol%) of p-hydroxymethylbenzoic acid was contained.

Example 4 In a 100 ml three-necked flask, 5 g of p-acetoxymethylbenzoic acid as an (acyloxyalkyl) aromatic carboxylic acid and 50 m of water were placed.
l and an acidic ion exchange resin (trade name: Amberlyst 15; manufactured by Organo Corporation) as an acid catalyst
g. Then, the aqueous solution in the flask was
The mixture was heated to 0 ° C. and subjected to a hydrolysis reaction for 1 hour with stirring.

After the completion of the reaction, the aqueous solution was cooled. Thereafter, the aqueous solution was filtered to separate an acid catalyst, and the composition of the aqueous solution was analyzed by liquid chromatography. As a result, the aqueous solution contained p-acetoxymethyl as the (hydroxyalkyl) aromatic carboxylic acid according to the present invention. It contained 3.2 g (yield 82 mol%) of p-hydroxymethylbenzoic acid, which is a hydrolysis product of benzoic acid.

Example 5 In a 50 ml autoclave,
P-Hydroxymethylbenzoic acid 3 as (hydroxyalkyl) aromatic carboxylic acids obtained in Example 4
g, 12 g of water and 6 g of methanol,
As a reduction catalyst, 0.6 g of activated carbon-supported ruthenium obtained by supporting ruthenium on activated carbon was added and sealed. The supported amount (content) of ruthenium in the reduction catalyst was 5% by weight.

Next, after the inside of the autoclave was replaced with nitrogen gas, hydrogen gas was introduced into the autoclave to pressurize the inside to 4.9 × 10 ⁶ Pa (gauge pressure). afterwards,
The autoclave was heated to 100 ° C., and a ring hydrogenation reaction was performed while stirring the reaction solution in the autoclave until hydrogen absorption disappeared.

After completion of the reaction, the reaction solution was cooled. Thereafter, the reaction solution was filtered to separate the reduction catalyst, and the composition of the reaction solution was analyzed by gas chromatography to find that the p-
The conversion of hydroxymethylbenzoic acid is 100 mol%, and the reaction mixture contains the reduced product of p-hydroxymethylbenzoic acid as the (hydroxyalkyl) cycloaliphatic carboxylic acids according to the present invention. 2.71 g (yield 87 mol%) of -hydroxymethylcyclohexanecarboxylic acid was contained.

[0146]

According to the production method of the present invention, an (acyloxyalkyl) aromatic carboxylic acid is used as a starting material, and a hydroxyalkylcyclohexanecarboxylic acid is obtained by a ring hydrogenation reaction (hydrogen reduction of an aromatic ring compound group) and a hydrolysis reaction. A novel method for producing (hydroxyalkyl) cycloaliphatic carboxylic acids, which produces (hydroxyalkyl) cycloaliphatic carboxylic acids such as acids, can be provided. According to the method, for example, raw materials for polyester-based paints and synthetic fibers, synthetic resins, and the like, for example, homopolyesters and compounds that are industrially very useful as raw materials for producing copolyesters with ethylene glycol and the like (Hydroxyalkyl) cycloaliphatic carboxylic acids such as hydroxyalkylcyclohexanecarboxylic acids and their precursors (intermediates for production) can be industrially, efficiently and inexpensively produced. .

Further, according to the present invention, it is possible to provide a catalyst which can be suitably used in the above production method.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C07C 65/01 C07C 65/01 // C07B 61/00 300 C07B 61/00 300

Claims (7)

[Claims] 1. A process for producing an (acyloxyalkyl) cyclic aliphatic carboxylic acid by hydrogen-reducing an aromatic ring compound group of an (acyloxyalkyl) aromatic carboxylic acid, and the (acyloxyalkyl) ring obtained by the above process. And a step of hydrolyzing the formula aliphatic carboxylic acids. 2. A process for producing (hydroxyalkyl) cycloaliphatic carboxylic acids, which comprises a step of hydrolyzing (acyloxyalkyl) cycloaliphatic carboxylic acids. 3. A process for producing (hydroxyalkyl) aromatic carboxylic acids by hydrolyzing (acyloxyalkyl) aromatic carboxylic acids, and an aromatic ring compound of the (hydroxyalkyl) aromatic carboxylic acids obtained by the above process. Hydrogen reducing the group; and (Hydroxyalkyl) cyclic aliphatic carboxylic acids. 4. The method according to claim 1, further comprising the step of reducing the aromatic ring compound group of the (hydroxyalkyl) aromatic carboxylic acid with hydrogen using a catalyst containing at least one element selected from rhodium and ruthenium. A) a process for producing cycloaliphatic carboxylic acids. 5. A process for producing (acyloxyalkyl) cycloaliphatic carboxylic acids, which comprises a step of hydrogenating an aromatic ring compound group of (acyloxyalkyl) aromatic carboxylic acids. 6. A compound represented by the general formula (1): R ⁶ COO—CR ¹ R ² —Z—COOH (1) wherein Z represents a divalent or more divalent alicyclic compound group having 6 or more carbon atoms; R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms,, R ² represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or -OCOR ⁵ groups, R ⁵ is a carbon number from 1 to 4
Wherein R ⁶ is a substituted carbon number of 1 to
6 alkyl groups, C1-6 alkene groups, C1
(Acyloxyalkyl) cycloaliphatic carboxylic acids represented by the following formulas: 7. A catalyst for use in hydrogen reduction of an aromatic ring compound group of a (hydroxyalkyl) aromatic carboxylic acid, wherein the catalyst contains at least one element selected from rhodium and ruthenium.