JP2011020949A - Method of dehydration condensation in water and catalyst usable for the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of dehydration condensation in water, for efficiently collecting a small amount of an organic compound contained in water (e.g. acetic acid) by converting the organic compound into a hydrophobic material by the dehydration condensation, and to provide a catalyst usable for the method and causing a very small amount of elution thereof into a water layer. <P>SOLUTION: The dehydration condensation is carried out in water by using an organic basic compound and a Broensted acid having a surfactant structure as a catalyst. Specifically, a carboxylic acid in the water and a hydrophobic alcohol are converted into a hydrophobic ester by using the catalyst, and the ester is collected from the aqueous phase to an organic phase (hydrophobic alcohol phase). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for carrying out a dehydration condensation reaction in water and a catalyst used in the method. More specifically, the present invention relates to a method for converting an organic substance contained in water into a hydrophobic substance by a dehydration condensation reaction, a catalyst used in the method, and a method for recovering an organic substance in an aqueous solution.

  In recent years, water has attracted attention as an inexpensive and safe medium because of consideration for the environment and the human body. However, performing an organic reaction in an aqueous medium without using an organic solvent has various problems and is difficult. The main problems are that many organic compounds do not dissolve in water, and that many of reagents such as catalysts and reaction intermediates are deteriorated and decomposed even by a small amount of water. In particular, the dehydration condensation reaction represented by the esterification reaction of an organic acid and an alcohol is generally reversible, and the reaction equilibrium is achieved by removing the generated water with a dehydrating agent or using a large excess of reaction substrate. It is necessary to incline in the direction in which the dehydration condensation reaction proceeds. Therefore, it has been recognized that it is difficult to carry out the dehydration condensation reaction in an aqueous medium.

  In addition, as an industrial application example of an underwater dehydration condensation reaction, for example, an organic substance in an aqueous solution in which an organic substance is dissolved and a higher alcohol insoluble in water are reacted to convert the organic substance into a hydrophobic substance, and the hydrophobic substance And a method of recovering the organic substance by removing the organic layer containing the organic substance from the aqueous layer. According to this method, it is possible to reduce the amount of organic matter in the aqueous solution. Especially when applied to industrial wastewater containing organic matter, not only can the cost of wastewater treatment be reduced, but the organic matter in the wastewater can be recovered as valuable resources. There are advantages you can do.

  As a method for performing a dehydration condensation reaction in water, a method using a Bronsted acid having a surfactant structure as a catalyst has been proposed (Japanese Patent Laid-Open No. 2003-55302; Patent Document 1). However, in this method, the Bronsted acid has a surfactant structure, and since an emulsion is formed during the reaction, it is difficult to separate the organic layer and the aqueous layer after the reaction, and the catalyst is eluted into the aqueous layer. Therefore, there is a problem that it is difficult to recover and reuse the catalyst.

  From the viewpoint of reusing the catalyst, a catalyst in which Bronsted acid is immobilized on a polymer carrier has been proposed (Adv. Synth. Cat. 344, 270 (2002); Non-Patent Document 1). However, such an immobilized catalyst is generally expensive because the preparation of the catalyst is complicated as compared with a homogeneous catalyst.

  On the other hand, a compound comprising diphenylamine and trifluoromethanesulfonic acid has been reported as a dehydration esterification catalyst in an organic solvent (Tetrahedron Lett., 41 (2000) 5249; Non-Patent Document 2). However, such a catalyst comprising an amine and a strong acid hardly functions in water for the same reason as described above, and the dehydration condensation reaction cannot be performed efficiently in an aqueous medium.

Japanese Patent Laid-Open No. 2003-55302

Adv. Synth. Cat. 344, 270 (2002) Tetrahedron Lett. , 41 (2000) 5249

  An object of the present invention is to provide a method for suppressing elution of a catalyst to an aqueous layer to a very low level while performing a dehydration condensation reaction in water at a high yield and selectivity, and a catalyst used therefor.

  The present inventors have intensively studied to solve the above problems. As a result, by using an organic base compound and a Bronsted acid having a surfactant structure as a catalyst, it is possible to efficiently perform a dehydration condensation reaction in water, and elution of the catalyst into the aqueous layer is extremely high. It was found that the catalyst can be easily recovered and reused because it is suppressed to a low level, and the present invention has been completed.

（式中、Ｍは窒素原子、りん原子またはひ素原子を表わし、Ｒ¹〜Ｒ³はそれぞれ独立して、水素原子、炭素数１〜１８のアルキル基、炭素数７〜２０のアラルキル基、または炭素数６〜２０のアリール基を表わし、Ｒ¹〜Ｒ³のうち少なくとも一つは前記アルキル基、アラルキル基またはアリール基である。Ｒ¹〜Ｒ³は結合して環構造を形成してもよい。）
で示される有機塩基化合物と界面活性剤構造を有するブレンステッド酸とを触媒として用いることを特徴とする水中脱水縮合反応方法。
［２］前記有機塩基化合物と前記界面活性剤構造を有する有機ブレンステッド酸との塩を触媒として用いる前項１に記載の水中脱水縮合反応方法。
［３］前記界面活性剤構造を有する有機ブレンステッド酸が、界面活性剤構造を有するスルホン酸である前項１または２に記載の水中脱水縮合反応方法。
［４］前記有機塩基化合物がアリールアミン化合物である前項１または２に記載の水中脱水縮合反応方法。
［５］前記アリールアミン化合物がジアリールアミン構造を有する化合物である前項４に記載の水中脱水縮合反応方法。
［６］前記ジアリールアミン構造を有する化合物が下記化合物（Ｂ−１）〜（Ｂ−７２）からなる化合物群の中から選択される前項５に記載の水中脱水縮合反応方法：

［７］前記脱水縮合反応が、カルボン酸、アルデヒド、及びケトンからなる群の中から選択される少なくとも１種と、アルコール及びチオールからなる群の中から選択される少なくとも１種との脱水縮合反応である前項１〜６のいずれかに記載の水中脱水縮合反応方法。
［８］前記脱水縮合反応が、酢酸と、炭素数８以上のアルコールとの脱水縮合反応である前項７に記載の水中脱水縮合反応方法。
［９］式（１）

（式中の記号は前項１の記載と同じ意味を表わす。）
で示される有機塩基化合物と界面活性剤構造を有するブレンステッド酸とからなることを特徴とする水中脱水縮合反応用触媒。
［１０］カルボン酸、アルデヒド及びケトンからなる群の中から選択される少なくとも１種の有機物が溶解している水溶液中の前記有機物と炭素数が８以上のアルコールとを、式（１）

（式中の記号は前項１の記載と同じ意味を表わす。）
で示される有機塩基化合物と界面活性剤構造を有するブレンステッド酸とを触媒として脱水縮合反応させて前記有機物を疎水性物質に変換し、前記疎水性物質を含む有機層を水層から除去することを特徴とする有機物回収方法。 That is, the present invention relates to the following [1] to [10].
[1] Formula (1)

(In the formula, M represents a nitrogen atom, a phosphorus atom or an arsenic atom, and R ^{1 to} R ³ each independently represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or Represents an aryl group having 6 to 20 carbon atoms, and at least one of R ^{1 to} R ³ is the alkyl group, the aralkyl group or the aryl group, and R ^{1 to} R ³ may combine to form a ring structure; Good.)
A dehydration-condensation reaction method in water, which comprises using, as a catalyst, an organic base compound represented by formula (2) and a Bronsted acid having a surfactant structure.
[2] The dehydration condensation reaction method in water according to item 1 above, wherein a salt of the organic base compound and the organic Bronsted acid having the surfactant structure is used as a catalyst.
[3] The dehydration condensation reaction method in water according to item 1 or 2, wherein the organic Bronsted acid having a surfactant structure is a sulfonic acid having a surfactant structure.
[4] The method for dehydration condensation reaction in water according to item 1 or 2, wherein the organic base compound is an arylamine compound.
[5] The dehydration condensation reaction method in water according to item 4, wherein the arylamine compound is a compound having a diarylamine structure.
[6] The dehydration condensation reaction method in water according to item 5 above, wherein the compound having a diarylamine structure is selected from the compound group consisting of the following compounds (B-1) to (B-72):

[7] The dehydration condensation reaction is a dehydration condensation reaction of at least one selected from the group consisting of carboxylic acid, aldehyde, and ketone and at least one selected from the group consisting of alcohol and thiol. 7. The underwater dehydration condensation reaction method according to any one of items 1 to 6 above.
[8] The underwater dehydration condensation reaction method according to item 7 above, wherein the dehydration condensation reaction is a dehydration condensation reaction between acetic acid and an alcohol having 8 or more carbon atoms.
[9] Formula (1)

(The symbols in the formula have the same meaning as described in item 1 above.)
A catalyst for dehydration condensation reaction in water, comprising an organic base compound represented by the formula (1) and a Bronsted acid having a surfactant structure.
[10] The organic substance and an alcohol having 8 or more carbon atoms in an aqueous solution in which at least one organic substance selected from the group consisting of carboxylic acid, aldehyde and ketone is dissolved is represented by the formula (1).

(The symbols in the formula have the same meaning as described in item 1 above.)
The organic base compound and the Bronsted acid having a surfactant structure are subjected to dehydration condensation reaction as a catalyst to convert the organic substance into a hydrophobic substance, and the organic layer containing the hydrophobic substance is removed from the aqueous layer. A method for recovering organic matter.

  According to the method and / or catalyst of the present invention, it is possible to perform a dehydration condensation reaction with high yield and selectivity in water, and since elution of the catalyst into the aqueous layer can be suppressed to a very low level, It can be recovered and reused, and the cost for recovering organic substances from the aqueous solution can be reduced.

6 is a schematic diagram of a counter-current contact type reaction apparatus used in Example 32. FIG.

Hereinafter, the present invention will be specifically described.
[Dehydration condensation reaction in water]
The dehydration condensation reaction in the present invention is a reaction in which two functional groups react, water is eliminated, and the two functional groups are combined. Specifically, ester formation reaction by reaction of carboxyl group and hydroxy group, amide formation reaction by reaction of carboxyl group and amino group, thioester formation reaction by reaction of carboxyl group and mercapto group, aldehyde group and hydroxy group Acetal formation reaction by reaction with aldehyde group, aldimine formation reaction by reaction of aldehyde group and amino group, thioacetal formation reaction by reaction of aldehyde group and mercapto group, formation of ketal by reaction of keto group and hydroxy group Formation reaction, Ketimine formation reaction by reaction of keto group and amino group, Formation reaction of thioketal by reaction of keto group and mercapto group, Formation reaction of ether by reaction of hydroxy group and hydroxy group, Alcohol and mercapto group Formation reaction of thioether by reaction Dehydration condensation reaction, and the like.

  The underwater dehydration condensation reaction in the present invention is a reaction performed in the presence of excess water (for example, 1 mass times or more) with respect to at least one of the reaction substrates in the dehydration condensation reaction.

[Reaction substrate]
The reaction substrate used in the reaction of the present invention is not particularly limited as long as it has a functional group that performs a dehydration condensation reaction.

  For example, as a compound having a carboxyl group in a reaction for forming an ester by dehydration condensation reaction between a carboxyl group and a hydroxy group (that is, carboxylic acid), formic acid, acetic acid, propionic acid, butyric acid, valeric acid, isovaleric acid, Saturated fatty acids such as 2-methylbutyric acid, pivalic acid, hexanoic acid, heptanoic acid, octanoic acid, 2-ethylhexanoic acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, oleic acid , Linoleic acid, linolenic acid, arachidonic acid, docosahexaenoic acid, eicosapentaenoic acid and other unsaturated carboxylic acids, benzoic acid, salicylic acid, cinnamic acid, phenylpropionic acid and other aromatic carboxylic acids, oxalic acid, malonic acid, succinic acid , Glutaric acid, adipic acid, fumaric acid, maleic acid, isophthalic acid , Dicarboxylic acids such as terephthalic acid, such as amino acids, and the like.

  Examples of the compound having a hydroxy group (ie, alcohol) include methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 1-nonanol, 1-decanol, 1-undecanol, 1-dodecanol, 1-tridecanol, 1-tetradecanol, 1-pentadecanol, 1-hexadecanol, 1-heptadecanol, 1-octadecanol, 1-nonadecanol, 1-eicosanol, Saturated alcohols having a linear structure such as 1-heneicosanol, 1-docosanol, 1-tetracosanol, 1-hexacosanol, iso-propanol, iso-butanol, sec-butanol, tert-butanol, 2- Octanol, 2-ethyl- -Saturated alcohol having a branched chain structure such as hexanol, 3,5,5-trimethyl-1-hexanol, 2-octyl-1-dodecanol, saturated alcohol having an alicyclic structure such as cyclohexanol, trans-2-dodecene- 1-ol, trans-2-tridecen-1-ol, trans-9-octadecene-1-ol, oleyl alcohol, cis, cis-9,12-octadecadien-1-ol, cis-13-docosene-1 -Unsaturated alcohols such as ol, benzyl alcohol, 1-phenylethyl alcohol, 2-phenylethyl alcohol, 3-phenylpropanol, alcohols having an aromatic ring such as diphenylcarbinol, ethylene glycol, 1,3-propanediol, 1 , 2-propanedio Le, diethylene glycol, and polyhydric alcohols such as pentaerythritol.

  In addition, compounds having a carboxyl group and a hydroxy group in the molecule, such as glycolic acid, lactic acid 2-hydroxybutyric acid, and 3-hydroxybutyric acid can also be used.

  Examples of the compound having a carboxyl group in a reaction for forming an amide by a dehydration condensation reaction between a carboxyl group and an amino group include the carboxylic acids described above.

  Examples of the compound having an amino group (namely, amine) include methylamine, ethylamine, propylamine, isopropylamine, butylamine, isobutylamine, hexylamine, octylamine, dodecylamine, octadecylamine, cyclohexylamine, phenylamine, p-tolylamine , Primary amines such as ethylenediamine, xylylenediamine, dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, dihexylamine, dioctylamine, didodecylamine, dioctadecylamine, dicyclohexylamine, diphenylamine, di-p-tolylamine And secondary amines.

Examples of the compound having a carboxyl group in a reaction for forming a thioester by a dehydration condensation reaction between a carboxyl group and a mercapto group include the carboxylic acids described above.
Examples of the compound having a mercapto group (ie, thiol) include methanethiol, ethanethiol, 1-propanethiol, 2-propanethiol, 1-butanethiol, 2-butanethiol, 2-methyl-2-propanethiol, 1- Hexanethiol, 1-octanethiol, 1-decanethiol, 1-dodecanethiol, 1-tetradecanethiol, 1-hexadecanethiol, 1-octadecanethiol, cyclohexanethiol, allyl mercaptan, benzenethiol, benzyl mercaptan, 2-phenylethyl mercaptan Etc. A compound having a carboxyl group and a mercapto group in the molecule, such as 3-mercaptopropionic acid, can also be used.

Examples of the compound having an aldehyde group in a reaction for generating an acetal by a dehydration condensation reaction between an aldehyde group and a hydroxy group include acetaldehyde, propionaldehyde, acrolein, benzaldehyde, cinnamaldehyde, and perylaldehyde. Examples of the compound having a hydroxy group include the alcohols.
Examples of the compound having a carboxyl group in a reaction for producing an aldimine by dehydration condensation reaction between an aldehyde group and an amino group include the above carboxylic acid, and examples of the compound having an amino group include the above amine.

Examples of the compound having an aldehyde group in a reaction for producing a thioacetal by a dehydration condensation reaction between an aldehyde group and a mercapto group include the thiols described above.
Examples of the compound having a keto group (that is, a ketone) in a reaction for producing a ketal by a dehydration condensation reaction between a keto group and a hydroxyl group include acetone, 2-butanone, methyl isobutyl ketone, 2-acetophenone, benzophenone, and the like.
Examples of the compound having a keto group in a reaction for producing a ketimine by a dehydration condensation reaction between a keto group and an amino group include the aforementioned ketone, and examples of the compound having an amino group include the aforementioned amine.

  Examples of the compound having a keto group in a reaction for producing a thioketal by dehydration condensation reaction between a keto group and a mercapto group include the above ketones, and examples of the compound having a mercapto group include the above thiols.

  Examples of the compound having a hydroxyl group in a reaction for producing an ether by a dehydration condensation reaction between a hydroxyl group and a hydroxyl group include the alcohols described above.

  Examples of the compound having a hydroxyl group in a reaction for producing a thioether by a dehydration condensation reaction between a hydroxyl group and a mercapto group include the above alcohol, and examples of the compound having a mercapto group include the above thiol.

  As an industrial application example of the underwater dehydration condensation reaction in the present invention, for example, an organic substance (for example, acetic acid) in an aqueous solution in which an organic substance is dissolved is reacted with a higher alcohol to convert the organic substance into a hydrophobic substance, There is a method in which the organic layer containing the hydrophobic substance is removed from the aqueous layer to recover the organic matter. As the higher alcohol in this method, those having 8 or more carbon atoms are preferable. If the number of carbon atoms is 8 or less, the solubility of alcohol in water is high, and organic substances cannot be efficiently removed and recovered from the aqueous layer.

[Organic base compounds]
In the present invention, an organic base compound represented by the following formula (1) is used as one of the catalyst components.

  In the above formula (1), M represents a nitrogen atom, a phosphorus atom or an arsenic atom. Among these, a nitrogen atom is particularly preferable in consideration of easy availability and less influence on the human body and the environment.

In the above formula (1), R ^{1 to} R ³ are each a hydrogen atom, an alkyl group having 1 to 18 carbon atoms (including a cycloalkyl group), an aralkyl group having 7 to 20 carbon atoms, or an aryl having 6 to 20 carbon atoms. Represents at least one of R ^{1 to} R ³ is an alkyl group or an aryl group. These groups may be further substituted by alkyl groups, aralkyl groups, aryl groups, alkoxy groups, acyl groups, alkoxycarbonyl groups, acyloxy groups, amide groups, nitro groups, halogen atoms, single bonds, oxygen atoms, sulfur A ring structure may be formed by bonding to each other via an atom or an alkylene group.

For a higher catalytic activity, it is preferable that at least one of R ¹ to R ³ is an aryl group, more preferably two of R ¹ to R ³ is an aryl group.

  Specific examples of the alkyl group having 1 to 18 carbon atoms (including a cycloalkyl group) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a 2-butyl group, an isobutyl group, and a tert group. -Butyl group, 1-pentyl group, 2-pentyl group, 3-pentyl group, 3-methylbutyl group, 1,1-dimethylpropyl group, n-hexyl group, 2-hexyl group, 3-hexyl group, 4-methyl Pentyl group, 2-ethylbutyl group, n-heptyl group, 2-heptyl group, 3-heptyl group, 4-heptyl group, n-octyl group, 2-octyl group, 3-octyl group, 4-octyl group, n- Ethylhexyl group, n-nonyl group, 2-nonyl group, 3-nonyl group, 4-nonyl group, 5-nonyl group, n-decyl group, 3,7-dimethyloctyl group, n-dodecyl group, n-tetradecyl group , N- hexadecyl group, 2-methyl hexadecyl group, n- octadecyl group, a cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group.

  Examples of the aralkyl group having 7 to 20 carbon atoms include benzyl group, 1-phenylethyl group, 2-phenylethyl group, 2- (1-phenyl) propyl group, and 3,3-diphenylpropyl group.

  Examples of the aryl group having 6 to 20 carbon atoms include phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,5-dimethylphenyl group, mesityl group, 4-tert-butylphenyl group, Examples include 4- (1,1,3,3-tetramethylbutyl) phenyl group, 2-biphenyl group, 3-biphenyl group, 4-biphenyl group, and 2,6-diphenylphenyl group.

Of these basic compounds, compounds having a diarylamine structure are particularly preferred. Specific examples thereof include the following compounds B-1 to B-72.

  Examples of phosphorus compounds include diphenylphosphine and bis (3,5-dimethylphenyl) phosphine, and examples of arsenic compounds include diphenylarsine.

[Bronsted acid having surfactant structure]
The Bronsted acid used as a catalyst component in the present invention includes a hydrophobic group having an affinity for a solvent having a small polarity and a hydrophilic group having a high affinity for a solvent having a high polarity such as water (Bronsted acid). And has a surfactant structure. Examples of the hydrophobic group structure include a hydrocarbon group, an aromatic hydrocarbon group, a fluorocarbon group, and a polymer, and a hydrocarbon group and an aromatic hydrocarbon group are particularly preferable. The hydrophilic group structure is Bronsted acid such as sulfonic acid, carboxylic acid, and phosphoric acid, and sulfonic acid is particularly preferable. That is, a compound having a hydrocarbon group or an aromatic hydrocarbon group and a sulfonic acid group or a carboxylic acid group is preferable.

  Examples of the surfactant type Bronsted acid used in the present invention include alkylbenzene sulfonic acids such as octylbenzene sulfonic acid, dodecyl benzene sulfonic acid and octadecyl benzene sulfonic acid, octane sulfonic acid, decane sulfonic acid, dodecane sulfonic acid, hexadecane sulfone. Acid, alkyl sulfonic acid such as octadecane sulfonic acid, alkyl naphthalene sulfonic acid, alkyl diphenyl ether disulfonic acid, 3-trimethylsilyl-1-propane sulfonic acid, perfluorooctane sulfonic acid and the like, preferably the above alkylbenzene sulfonic acid and alkyl sulfone An acid, particularly preferably dodecylbenzenesulfonic acid.

  In the present invention, a catalyst previously mixed with an organic base compound and a Bronsted acid having a surfactant structure may be used, or may be added separately when reacting. Moreover, the molar ratio of the base part (M in the formula (1), that is, the N part, the P part or the As part) of the organic base compound to the Bronsted acid is 1:10 to 10: 1, preferably 1: 2 to 2. 2: 1, particularly preferably 1: 1. If the amount of the organic base compound is too large, the catalytic action of the Bronsted acid is reduced. If the amount of the organic base compound is too small, elution of the Bronsted acid into the aqueous layer increases.

  Examples of the method of mixing the organic base compound and the Bronsted acid having a surfactant structure in advance include, for example, a method of directly mixing the both, and the organic base compound and the Bronsted acid having a surfactant structure are both well dissolved. A method of removing the organic solvent after dissolving in an organic solvent (for example, hexane etc.) is mentioned.

  The organic base compound and the Bronsted acid having a surfactant structure preferably form a salt. By forming the salt, elution of the Bronsted acid into the aqueous layer is suppressed.

Whether or not the organic base compound and the Bronsted acid having a surfactant structure form a salt is determined by measuring the ¹ H-NMR spectrum, a peak attributed to the Bronsted acid having a surfactant structure in the mixture. This chemical shift can be confirmed by a shift compared to the chemical shift in the case of only Bronsted acid having a surfactant structure. For example, when dodecylbenzenesulfonic acid (DBSA), which is a Bronsted acid having a surfactant structure, forms a salt with an organic base compound, the peak derived from the benzene ring portion of DBSA is 0.1 compared to that before salt formation. Shift to high magnetic field side by ~ 0.3ppm.

[Reaction method]
The reaction method is not particularly limited, and examples thereof include stirring, a method using a line mixer, and a countercurrent contact method.

[solvent]
In the dehydration condensation reaction in the present invention, an organic solvent can be used as necessary. When a solvent is used, the reaction yield may be increased. As the organic solvent, a solvent which is incompatible with water and separates into two layers is preferable. For example, aliphatic hydrocarbons such as hexane, aromatic hydrocarbons such as toluene and xylene, ethers such as diethyl ether, tert-butyl methyl ether and dibenzyl ether, ketones such as 2-octanone and diisobutyl ketone, Examples include higher alcohols such as 1-octanol, 1-dodecanol, 1-hexadecanol, 2-octyldodecanol, and 3,7-dimethyl-3-octanol. Moreover, you may use the said ketones and alcohol as what also serves as a reaction substrate.

[Amount of catalyst]
The used amount (catalytic amount) of the Bronsted acid having a surfactant structure used as a catalyst component in the present invention is 0.1 to 1000 mol with respect to the smaller one of the two substrates to be reacted. % Is preferred. A particularly preferable amount of catalyst varies depending on the reaction system. For example, it is 0.1 to 10 mol% in a batch type reaction, and 10 to 1000 mol% in a countercurrent contact type continuous reaction. In the case of a batch reaction, if it is carried out in an amount less than 0.1 mol%, a preferable reaction rate cannot be obtained, and if it is more than 10 mol%, the cost for the catalyst increases, which is not economically preferable. In the case of a counter-current contact type continuous reaction, if the amount is less than 10 mol%, the average residence time is undesirably long, and if it exceeds 1000 mol%, the viscosity of the reaction system becomes high and stirring becomes difficult, or the catalyst remains undissolved. Sometimes.

[Reaction temperature]
There is no restriction | limiting in particular in the reaction temperature in this invention, Although the reaction temperature according to the objective can be set, the range of 20-120 degreeC is preferable. More preferably, it is the range of 25 degreeC-105 degreeC. If the temperature is too low, the reaction rate is slow, and if it exceeds 120 ° C., the energy cost is increased, which is not preferable.

[Reaction pressure]
The reaction pressure is not particularly limited, and any conditions can be selected. However, from the viewpoint of energy cost, a range from normal pressure to 0.1 MPaG is preferable.

[Reaction time]
The reaction time is not particularly limited. The reaction time can be selected according to the purpose. The reaction time varies depending on the temperature, pressure and reaction mode, but in the case of a batch reaction, it is in the range of 5 minutes to 5 hours, more preferably in the range of 10 minutes to 3 hours, more preferably in the range of 30 minutes to 1.5 hours. .

[Recovering organic substances in water]
A small amount of a hydrophilic organic compound such as carboxylic acid, aldehyde, or ketone dissolved in water is subjected to dehydration reaction in water with a hydrophobic alcohol, preferably an alcohol having 8 or more carbon atoms, in the presence of the catalyst of the present invention. Convert to hydrophobic ester compounds. The produced hydrophobic ester compound forms an organic layer together with excess hydrophobic alcohol as one reaction substrate, a catalyst (the Bronsted acid salt), and a solvent. By separating the organic layer and the original aqueous layer by a known method (for example, static separation method), the carboxylic acid or the like can be recovered from the aqueous layer to the organic layer. In order to avoid dissolution of the organic substance in the aqueous layer, the solvent and the catalyst are also preferably hydrophobic substances. The hydrophobic substance is a substance that is separated into an aqueous layer and an organic layer having a solubility in water of generally 10 g / L or less.

EXAMPLES Hereinafter, although a synthesis example, an Example, and a comparative example demonstrate this invention further, this invention does not receive any limitation by these description.
In addition, the organic base compounds (B-1), (B-7), (B-10), (B-13), (B-30), (B-36), (B-) used in each Example 44), (B-52), (B-53), (B-54), (B-55), (B-56), (B-60), (B-64), (B-65) And dodecylbenzenesulfonic acid (DBSA) and pentafluorobenzenesulfonic acid (C ₆ F ₅ SO ₃ H) were obtained from Tokyo Chemical Industry Co., Ltd. The organic base compound (B-11) was obtained from Seiko Chemical Co., Ltd. The organic base compound (B-72) was obtained from Sigma Aldrich Japan Co., Ltd.

Synthesis Example 1 Synthesis of Organic Base Compound (B-9) After mesityl bromide (5 mmol) and mesitylamine (5 mmol) were dissolved in dehydrated toluene (10 ml), tert-butoxy sodium (15 mmol), palladium acetate (0.1 mmol) ), 2-dicyclohexylphosphino-2 ′, 4 ′, 6′-triisopropylbiphenyl (0.15 mmol) was added, and the mixture was reacted by heating under reflux in an argon atmosphere for 3 hours. After the reaction, the reaction mixture was cooled to room temperature, insoluble matters were removed by Celite filtration, and Celite was washed with toluene. The filtrate and the washing solution were combined and concentrated, and then purified by a silica gel column (eluent: mixed solvent of toluene / hexane), and the solvent was distilled off to obtain compound (B-9).

  In the same manner, using the corresponding bromide and amine compound as raw materials, compounds (B-14), (B-16), (B-19), (B-24), (B-25) , (B-26), (B-27), (B-28), (B-43), (B-49) and (B-63) were synthesized.

Synthesis Example 2: Synthesis of organic base compound (B-68) Diphenylamine (10 mmol), 1-octadecanol (10 mmol), tris (triphenylphosphine) dichlororuthenium (0.1 mmol) and triphenylphosphine (0.4 mmol) And heated to 140 ° C. for 2 hours in an argon atmosphere. After the reaction, the reaction mixture was cooled to room temperature, purified with a silica gel column (eluent: toluene / hexane mixed solvent), and the solvent was distilled off to obtain compound (B-68).

  By the same method, compounds (B-70) and (B-71) were synthesized using the corresponding amine and alcohol as raw materials.

Synthesis Example 3: Synthesis of salt composed of organic base compound (B-1) and dodecylbenzenesulfonic acid Compound (B-1) (1 mmol) and dodecylbenzenesulfonic acid (DBSA) (1 mmol) were dissolved in hexane (5 ml). After stirring for 5 minutes at room temperature, hexane was distilled off under reduced pressure to obtain a viscous liquid. ^{From 1} H-NMR, it was confirmed to be a 1: 1 (molar ratio) salt of compound (B-1) and DBSA. That is, in deuterated chloroform, the peaks at 7.29 ppm and 7.83 ppm derived from the benzene ring of DBSA when measured with DBSA alone were shifted to a high magnetic field to 7.03 ppm and 7.74 ppm, respectively.
In the same manner, compounds (B-7), (B-9), (B-10), (B-13), (B-14), (B-16), (B-19), (B -24), (B-25), (B-26), (B-27), (B-28), (B-30), (B-36), (B-43), (B-44) ), (B-49), (B-52), (B-53), (B-54), (B-55), (B-56), (B-60), (B-63), 1: 1 salt (molar ratio) of (B-64), (B-65), (B-68), (B-70), (B-71) and (B-72) and DBSA, respectively. It was synthesized and confirmed to form a 1: 1 salt by ¹ H-NMR.

Example 1:
A salt of a compound (B-1) synthesized in Synthesis Example 3 and DBSA (molar ratio 1: 1) was charged in an eggplant-shaped flask with 0.5 g of a 1.0 mass% aqueous acetic acid solution and 0.5 g of 2-octyl-1-dodecanol. 0.04 g of 1) was added, and the reaction was carried out at 80 ° C. for 1 hour with constant stirring to esterify acetic acid to convert it into 2-octyl-1-dodecyl acetate, which is a hydrophobic substance. The obtained reaction solution was separated into an aqueous layer and an organic layer with a separatory funnel. Component quantification of each of the aqueous layer and the organic layer was performed by ¹ H-NMR. ¹ H-NMR measurement of the aqueous layer was performed in deuterated methanol (CD ₃ OD) using sodium 3-trimethylsilyl-1-propanesulfonate as an internal standard substance. The ¹ H-NMR measurement of the organic layer was performed in deuterated chloroform (CDCl ₃ ) using hexamethyldisilane as an internal standard substance. As a result, the yield of 2-octyl-1-dodecyl acetate (ODA) based on acetic acid was 60%. At this time, DBSA eluted into the aqueous layer was an amount corresponding to 3.3% of the amount of DBSA added first. The acetic acid concentration in the aqueous layer at this time was 0.26%, and the acetic acid recovery rate to the organic layer combining acetic acid and ODA was 74%.

Examples 2-31:
Example 1 except that the salt of the organic base compound (B-1) and DBSA used in Example 1 was changed to 0.04 g of the combination of the compounds shown in Table 1 (molar ratio 1: 1). The reaction was performed in the same manner. The results are shown in Table 1.

Comparative Example 1:
The reaction was performed in the same manner as in Example 1 except that 0.04 g of DBSA was added instead of the salt of the organic base compound (B-1) and DBSA. The results are shown in Table 1.

Comparative Example 2:
Instead of the salt of the organic base compound (B-1) and DBSA, the organic base compound (B-1) of Synthesis Example 3 is changed to the compound (B-9), and DBSA is changed to pentafluorobenzenesulfonic acid (C ₆ F ₅ sO ₃ H) synthesis salt in the same manner as in synthesis example 3 was changed to (molar ratio 1: 1) except that addition of 0.04g was subjected to reaction in the same manner as in example 1. The results are shown in Table 1.

  As described above, when the reaction was carried out without adding an organic base compound, DBSA was often eluted into water (Comparative Example 1), and a Bronsted acid having no surfactant structure was used. The yield of the target product is extremely low (Comparative Example 2), but by using the dehydration reaction method of the present invention, elution of the catalyst into water can be reduced and the target product can be obtained in high yield. Can do.

Example 32:
FIG. 1 shows a 2-octyl-1-dodecanol solution containing a 1.0 mass% acetic acid aqueous solution and 14 mass% of a salt (molar ratio 1: 1) of compound (B-10) and dodecylbenzenesulfonic acid (DBSA). Using a counter-current contact type device (1) having a schematic configuration, a 2-octyl-1-dodecanol solution from an oil layer introduction part (3a) and an acetic acid aqueous solution from a water layer introduction part (4a) are continuously counterflowed. The esterification of acetic acid was carried out. In addition, 80 degreeC warm water was poured into the jacket part (2) of the reaction tube shown in FIG. 1 from the warm water introduction part (6a), and the McMahon type filling (5) was filled in the part where the two liquids flow in the counterflow. . The flow rates of the two liquids are the same volume (1.0 mL / min), and the residence time is 10 minutes. Each component analysis of the obtained water layer and organic layer was performed by gas chromatography. As a result, the yield of 2-octyl-1-dodecyl acetate (ODA) was 24%. At this time, DBSA eluted into the aqueous layer was an amount corresponding to 4% of the amount of DBSA contained in the salt added to 2-octyl-1-dodecanol.

Example 33:
The reaction was conducted in the same manner as in Example 32, except that the salt of compound (B-10) and DBSA of Example 32 was changed to the salt of compound (B-11) and DBSA (molar ratio 1: 1). It was. As a result, the yield of 2-octyl-1-dodecyl acetate (ODA) was 27%. At this time, DBSA eluted into the aqueous layer was an amount corresponding to 8% of the amount of DBSA contained in the salt added to 2-octyl-1-dodecanol.

Comparative Example 3:
The reaction was carried out in the same manner as in Example 32 using a 1.0% by mass acetic acid aqueous solution and a 2-octyl-1-dodecanol solution containing 8% by mass DBSA. As a result, the yield of 2-octyl-1-dodecyl acetate (ODA) was 29%. At this time, DBSA eluted into the aqueous layer was an amount corresponding to 37% of the amount of DBSA added to 2-octyl-1-dodecanol.
Also in this case, when the reaction is carried out without adding an amine compound, DBSA is often eluted into water.

DESCRIPTION OF SYMBOLS 1 Apparatus 2 Jacket part 3a Oil layer introduction part 3b Oil layer discharge part 4a Water layer introduction part 4b Water layer discharge part 5 Filler 6a Hot water introduction part 6b Hot water discharge part

Claims (10)

Formula (1)

(In the formula, M represents a nitrogen atom, a phosphorus atom or an arsenic atom, and R ^{1 to} R ³ each independently represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or Represents an aryl group having 6 to 20 carbon atoms, and at least one of R ^{1 to} R ³ is the alkyl group, the aralkyl group or the aryl group, and R ^{1 to} R ³ may combine to form a ring structure; Good.)
A dehydration-condensation reaction method in water, which comprises using, as a catalyst, an organic base compound represented by formula (2) and a Bronsted acid having a surfactant structure.   The dehydration condensation reaction method in water according to claim 1, wherein a salt of the organic base compound and the organic Bronsted acid having the surfactant structure is used as a catalyst.   The method for dehydration condensation in water according to claim 1 or 2, wherein the organic Bronsted acid having a surfactant structure is a sulfonic acid having a surfactant structure.   The method for dehydration condensation reaction in water according to claim 1 or 2, wherein the organic base compound is an arylamine compound.   The method for dehydration condensation reaction in water according to claim 4, wherein the arylamine compound is a compound having a diarylamine structure. The method for dehydration condensation reaction in water according to claim 5, wherein the compound having a diarylamine structure is selected from the group of compounds consisting of the following compounds (B-1) to (B-72):

  The dehydration condensation reaction is a dehydration condensation reaction of at least one selected from the group consisting of carboxylic acids, aldehydes, and ketones and at least one selected from the group consisting of alcohols and thiols. Item 7. The dehydration condensation reaction method in water according to any one of Items 1 to 6.   The dehydration condensation reaction method in water according to claim 7, wherein the dehydration condensation reaction is a dehydration condensation reaction between acetic acid and an alcohol having 8 or more carbon atoms. Formula (1)

(The symbols in the formula have the same meaning as described in claim 1.)
A catalyst for dehydration condensation reaction in water, comprising an organic base compound represented by the formula (1) and a Bronsted acid having a surfactant structure. The organic substance in an aqueous solution in which at least one organic substance selected from the group consisting of a carboxylic acid, an aldehyde, and a ketone is dissolved and an alcohol having 8 or more carbon atoms are represented by the formula (1).

(The symbols in the formula have the same meaning as described in claim 1.)
The organic base compound and the Bronsted acid having a surfactant structure are subjected to dehydration condensation reaction as a catalyst to convert the organic substance into a hydrophobic substance, and the organic layer containing the hydrophobic substance is removed from the aqueous layer. A method for recovering organic matter.

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