JP4387016B2 - Method for producing α, β-unsaturated ketone - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a process for producing an α, β-unsaturated ketone useful as an intermediate for agricultural medicine.
[0002]
[Prior art]
Conventionally, several methods for synthesizing an α, β-unsaturated ketone represented by the general formula (I) by condensation of an alkali metal acetoacetate and an aldehyde have been reported.
For example, Japanese Patent Application Laid-Open No. 57-4930 describes that an alkali metal salt of acetoacetic acid and an aldehyde are reacted in a mixture of a poorly water-soluble organic solvent and water using an aliphatic secondary amine as a catalyst. ing.
[0003]
JP-A-3-161456 discloses a reaction similar to that described above as a useful reaction particularly when an aldehyde having a side chain at the α-position is used. It is described that the reaction is carried out by adjusting the amount of water while keeping the pH constant with a mineral acid.
[0004]
[Problems to be solved by the invention]
However, the presence of a small amount of iron ions of about several ppm in these reaction systems hinders the reaction, revealing a problem that a large amount of β-hydroxyketone is produced as a by-product and the yield is remarkably reduced. In order to suppress such inhibition of iron ions, attempts have been made to use chelating agents that capture iron ions (for example, 2,2′-bipyridyl, 1,10-phenanthroline, etc.), but the suppression effect is weak and the base is recovered. In this process, these chelating agents are precipitated, and there is a problem that the liquid separation property is extremely deteriorated.
[0005]
The present invention provides a production method in which α, β-unsaturated ketone, which is the target product, is obtained in high yield even when iron ions, which are reaction inhibitors, are present in the reaction system, and are free from industrial problems. To do.
[0006]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors have made α and β aimed at high yields by allowing specific acids or their alkali metal salts or alkaline earth metal salts to be present in the reaction system. The inventors have found that an unsaturated ketone can be obtained and have completed the present invention.
[0007]
That is, the present invention relates to (1) an alkali metal salt or alkaline earth metal salt of aceto acid in a mixed solvent of water and a poorly water-soluble organic solvent in the presence of a base and the general formula (I)
[Chemical 3]
R ¹ CHO
(In the formula, R ¹ is an optionally substituted alkyl group, an optionally substituted hydrocarbon group having a C3 or higher alicyclic skeleton, and a hydrocarbon having the alicyclic skeleton. alkyl group having a group, in a reaction of an aldehyde represented by the representative.) which may have a substituent multiple ring group, or a phenyl group which may have a substituent, suppressing the influence of iron ions for, 0.1～30Mol phosphoric acid, polyphosphoric acid, and with respect to the aldehyde of the general formula (I) at least one or more selected from the group consisting of alkali metal salts or alkaline earth metal salts % General formula (II)
[Formula 4]
(Wherein, R ¹ represents. The same group as the) alpha represented by relates to the production how of β- unsaturated ketone.
[0008]
More specifically, (2) base is α according to the above (1), which is a secondary aliphatic amine, relates to the manufacturing method of β- unsaturated ketones.
[0009]
(3) Production of α, β-unsaturated ketone as described in (1) or (2) above , wherein the pH is kept within a certain range during the reaction, preferably within the range of pH 6-8. relates to a method, (4) in the general formula (I) medium-R ^1, according to any one of the above and having at least 1 or more substituents at the 1-position (1) ~ (3) alpha, beta - relates to the manufacturing method of the unsaturated ketone.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Specific examples of the alkali metal salt or alkaline earth metal salt used in the present invention include sodium acetoacetate, potassium acetoacetate, lithium acetoacetate, magnesium acetoacetate, and calcium acetoacetate.
[0011]
These salts can be easily prepared as an aqueous solution by, for example, hydrolyzing diketene or acetoacetate with an aqueous solution of sodium hydroxide, potassium hydroxide, magnesium hydroxide, etc., and then removing by-product alcohol by concentration under reduced pressure. can get. In the next reaction, the concentration of the aqueous solution thus obtained is preferably adjusted to a concentration of 40 to 50% because the yield decreases when a large amount of water is present.
[0012]
In general formula (I), R ¹ is an alkyl group which may have a substituent, a group which may have a substituent, or an alicyclic skeleton having at least C3 which may have a substituent. A hydrocarbon group having a hydrocarbon group, an alkyl group having a hydrocarbon group having an alicyclic skeleton, a multi-ring group optionally having a substituent, a multi-ring alkyl group optionally having a substituent, and a substituent Represents a phenyl group which may have a substituent, or a phenylalkyl group which may have a substituent.
[0013]
Specific examples of the aldehyde represented by the general formula (I) include isobutyraldehyde, 2-methylbutanal, 2-methylpentanal, 2,3-dimethylbutanal, 2-methylhexanal, 2-ethylhexanal, Aliphatic aldehydes branched at the α-position of aldehydes such as 2-ethylpentanal, 2-methylheptanal, 2-methylnonal, cyclohexanecarbaldehyde, 2-methylcyclohexanecarbaldehyde, 3-methylcyclohexanecarbaldehyde, 4- Aldehydes having an alicyclic group such as methylcyclohexanecarbaldehyde, heterocyclic aldehydes such as 4-tetrahydropyrancarbaldehyde, 2-tetrahydrofurancarbaldehyde, 3-tetrahydropyrancarbaldehyde, 3-tetrahydrothiopyrancarbaldehyde, Aromatic aldehydes such as benzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, p-methylthiobenzaldehyde, p-chlorobenzaldehyde, phenylalkylaldehydes such as benzylaldehyde and 1-methylbenzylaldehyde, 2-pyridyl Examples thereof include heterocyclic alkyl aldehydes such as methyl aldehyde and 2-pyridyl-1-methyl aldehyde.
[0014]
Among these, the method of the present invention is preferably applied to a reaction using an aldehyde having at least one substituent at the 1-position in R ¹ in the general formula (I), and particularly an aldehyde having a high water solubility. Specific examples of such aldehydes include aldehydes having a highly water-soluble 6-membered heterocyclic group having an oxygen atom or sulfur atom such as 4-tetrahydropyrancarbaldehyde and 3-tetrahydrothiopyrancarbaldehyde. be able to.
[0015]
Specific examples of the base used in the present invention include pyrrolidine, morpholine, piperazine, 3,5-dimethylpiperidine, 3-butylpiperidine, 3-hexylpiperidine, 3-cyclohexylpiperidine, 4-benzylpiperidine, 4-phenyl. Piperidines such as piperidine and 1,3-dipiperidylpropane, hexamethyleneimine, heptamethyleneimine, 3,3,5-trimethylhexahydroazepine, 1,2,3,4-tetrahydroisoquinoline, decahydroisoquinoline, 4- Cyclic amines such as methyldecahydroisoquinoline and 3-azabicyclo (3,2,2) nonane, dimethylamine, diethylamine, di-n-propylamine, N-methyl-Nn-butylamine, N-ethyl-Nn -Butylamine, N-methyl-Nn-amino Amine, N- methyl -N-n-hexylamine, can be exemplified dialkyl amines such as N- methyl -N- benzylamine. However, bulky amines such as di-i-propylamine and dicyclohexylamine are not preferred.
Further, when R ¹ has one or more substituents at the 1-position, it is preferable to use cyclic amines and N-methyl-N-substituted methylamines, and among them, it is preferable to use decahydroisoquinoline.
[0016]
The method of the present invention is characterized by reacting in the presence of specific acids or their salts in order to suppress the influence of iron ions and the like. Specifically, phosphoric acid, metaboric acid, silicic acid, polyphosphoric acid And at least one selected from the group consisting of alkali metal salts or alkaline earth metal salts thereof.
The amount to be used depends on the amount of iron ions present in the reaction system, but it is preferably 500 times or more, particularly 1500 times or more in terms of a molar ratio to iron ions. If the amount of iron ions mixed in the reaction system can be grasped, the amount of use can be determined from the molar ratio, but the amount of use can also be determined by the mole fraction (mol%) relative to the aldehyde of the raw material. When the raw material aldehyde is used as a reference, the amount used is preferably in the range of 0.1 to 30 mol%. When the amount used exceeds 30 mol%, the pH of the reaction solution is below 6.0, so the reaction is slowed and the yield tends to decrease. In addition, when it is necessary to use more than this amount, even if the pH of the reaction solution temporarily falls below the optimum pH for the reaction, the reaction is started by raising the pH at the start of the reaction to the optimum pH with an alkali such as NaOH. Can be done. However, when an aqueous solution is used as the alkali to be added, the amount of water in the system increases, the reaction slows down, and the acetoacetate salt may be easily decomposed. In addition, since the acetoacetate salt is easily decomposed under acidic conditions, it is preferable to quickly adjust the pH to an optimum value.
When adding an alkali metal salt such as phosphoric acid, the amount used is not particularly limited as long as the pH during the reaction is controlled within the optimum pH range.
[0017]
In order to reduce the amount of water in the system, it is preferable to use phosphoric acid having a low water content, but 75% phosphoric acid can also be used. Since high concentration phosphoric acid freezes in winter, 75% phosphoric acid is preferred for industrial use.
[0018]
Examples of the poorly water-soluble solvent used in the present invention include aromatic hydrocarbons such as toluene, benzene and xylene, and aliphatic hydrocarbons such as hexane, heptane, cyclohexane and decalin. The range of the mixing ratio of these solvent and water is 100: 5 to 100, but 100: 5 to 30, more preferably 100: 10 to 20 is preferable.
[0019]
The method of the present invention includes (1) a method of adding acetoacetic acid salt, base, phosphoric acid and the like to water and a poorly water-soluble solvent, and adding an aldehyde, and (2) aldehyde, base and phosphoric acid in water and a poorly water-soluble solvent. Etc., and a method of adding acetoacetate, (3) a method of adding aldehyde, phosphoric acid, etc. to water, a poorly water-soluble solvent, and adding an aqueous solution of acetoacetate or base, etc. can be employed. . When pH adjustment is required, the method (1) is most preferable.
[0020]
The optimum pH range varies depending on the aliphatic secondary amine to be used, but the pH range of the reaction solution during the reaction is preferably kept at a certain range, and more preferably kept at pH 6-8. If the pH is 6 or less, the reaction is slow and the yield tends to decrease. If the pH is 8 or more, the amount of by-product of the intermediate β-hydroxyketone tends to increase. Therefore, it is preferable to adjust to the said pH range using acids, such as a mineral acid, during reaction.
[0021]
The acid used for maintaining the pH is preferably a mineral acid. In order to reduce the amount of water in the system, concentrated sulfuric acid, an acid having a low water content such as 85% phosphoric acid, an acidic gas such as hydrogen chloride gas or sulfuric anhydride, It is preferable to use an acid anhydride such as phosphorus pentoxide. In addition, even with concentrated hydrochloric acid having a high water content, the reaction proceeds smoothly by using an aqueous solution of the alkali metal acetoacetate as a raw material at a high concentration. When phosphoric acid is used as the mineral acid, there is no particular problem even if iron ions are present in the reaction system as long as the molar ratio of iron ions to phosphoric acid is sufficiently secured.
[0022]
The reaction temperature is usually in the range of 10 to 60 ° C., but the higher the reaction temperature, the more the by-product of the intermediate β-hydroxyketone body increases, so the yield tends to decrease. Therefore, it is preferable to perform the reaction in a temperature range of 10 to 40 ° C.
[0023]
Specific examples of the method of the present invention are shown below.
10 to 1000 ml, preferably 100 to 800 ml of poorly water-soluble organic solvent is added to 1 to 3 moles of an acetoacetate aqueous solution with respect to 1 mole of the aldehyde represented by the general formula (I). Thereafter, 0.01 mol or more, preferably 0.05 to 0.20 mol of base is added to 1 mol of aldehyde. In a sufficiently stirred state, 0.001 mol to 0.30 mol is added to 1 mol of aldehyde and at least one selected from the group consisting of phosphoric acid, metaboric acid, silicic acid, and alkali metal salts thereof, and an acid. To adjust the pH to 6.0-8.0.
[0024]
Then, while maintaining the pH at 6.0 to 8.0 with acid at 10 to 60 ° C., 1 mol equivalent of aldehyde is added and stirred for 1 to 10 hours. After completion of the reaction, water is added and an acid is added to bring the pH to 2 or less, and the organic layer is separated from the aqueous layer. Further, the organic layer is neutralized with an alkali and washed with water to separate the organic layer from the aqueous layer, and the organic layer is concentrated under reduced pressure to obtain the desired α, β-unsaturated ketone.
[0025]
In addition, the base used as a catalyst can be recovered by 97% or more by extracting the aqueous layer separated from the organic layer with an alkali such as sodium hydroxide to a pH of 13 or more and extracting with a poorly water-soluble organic solvent. It can be reused. In addition, the poor liquid separation observed when a chelating agent was used instead of phosphoric acid or the like was not a problem in this case.
[0026]
【Example】
The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.
[0027]
Example 1
A reactor with an internal volume of 1000 ml was charged with 371.6 g (3.2 moles) of acetoacetic acid methyl ester and 134.4 g of ion-exchanged water, and 2.8 ppm of iron ions were maintained while maintaining the internal temperature at 35 to 40 ° C. with stirring with water. 537.6 g (3.36 mol) of a 25% NaOH aqueous solution was added dropwise over 4 hours, and then stirring was continued for 2 hours at 35 to 40 ° C. Then, water and methanol were distilled off under reduced pressure at a temperature of 40 ° C. or lower. A part of the contents of the flask was taken out and subjected to pH titration with a 1N standard hydrochloric acid aqueous solution. As a result, the concentration of the obtained aqueous sodium acetoacetate solution was 49%. From this aqueous sodium acetoacetate solution, 176.7 g (0.695 mol) was weighed and placed in a reactor having an internal volume of 1000 ml, followed by 150 ml of toluene, 6.96 g (0.05 mol) of decahydroisoquinoline, and 85% phosphoric acid. 0 g (0.043 mol) was added, and the pH was adjusted to 7.4 with concentrated sulfuric acid. 4-tetrahydropyran carbaldehyde 57.1g (0.5 mol) was dripped in this over 1 hour, Then, stirring was continued for 3 hours. During the reaction, the temperature was maintained at 20 to 25 ° C., and concentrated sulfuric acid was added dropwise to maintain the pH at 7.4 ± 0.1. After completion of the reaction, 80.0 g of water was added, and the temperature was raised to 65 ° C. with concentrated sulfuric acid at pH 1.5, and then the organic layer was separated from the aqueous layer. To the separated aqueous layer, 37.5 ml of toluene was added for extraction, and the organic layer was separated from the aqueous layer and then mixed with the first separated organic layer. The organic layer was neutralized by adding 2.3 g of 25% NaOH aqueous solution, and then the organic layer was separated from the aqueous layer. Further, 10 g of water was added to the organic layer, and the mixture was stirred and washed with water. The organic layer was separated from the aqueous layer and then dried over anhydrous magnesium sulfate. After magnesium sulfate was filtered off, the solvent was distilled off under reduced pressure, and the remaining oil was further distilled off under reduced pressure to obtain 73.9 g of a colorless oil having a boiling point of 91 to 95 ° C. (0.013 kPa). When analyzed by gas chromatography (crude yield 95.8%), the purity of the desired product 4- (4-tetrahydropyranyl) -3-buten-2-one was 95.1%. (Yield 91.2%) In addition, 4.9% of 4-hydroxy-4- (4-tetrahydropyranyl) -butan-2-one as a by-product was contained, and the yield based on 4-tetrahydropyrancarbaldehyde Was 4.2%.
[0028]
Example 2
The same 49% aqueous solution of sodium acetoacetate as synthesized in Example 1 (176.7 g, 0.695 mol) was placed in a reactor having an internal volume of 1000 ml, and then 150 ml of toluene and 6.96 g (0.05 mol) of decahydroisoquinoline. 85% phosphoric acid (2.5 g, 0.022 mol) was added, and the pH was adjusted to 7.4 with concentrated sulfuric acid. 4-tetrahydropyran carbaldehyde 57.1g (0.5 mol) was dripped in this over 1 hour, Then, stirring was continued for 3 hours. During the reaction, the temperature was maintained at 20 to 25 ° C., and concentrated sulfuric acid was added dropwise to maintain the pH at 7.4 ± 0.1. After completion of the reaction, 80.0 g of water was added, and the temperature was raised to 65 ° C. with concentrated sulfuric acid at pH 1.5, and then the organic layer was separated from the aqueous layer. To the separated aqueous layer, 37.5 ml of toluene was added for extraction, and the organic layer was separated from the aqueous layer and then mixed with the first separated organic layer. After neutralizing the organic layer by adding 5.2 g of 25% NaOH aqueous solution, the organic layer was separated from the aqueous layer. Further, 10 g of water was added to the organic layer, and the mixture was stirred and washed with water. The organic layer was separated from the aqueous layer and then dried over anhydrous magnesium sulfate. After filtering off magnesium sulfate, 256.1 g of an organic layer was obtained. A part of the organic layer was sampled and analyzed by high performance liquid chromatography by an internal standard method using a standard product having a purity of 99.9%. As a result, the desired product 4- (4-tetrahydropyranyl) -3-butene-2 The concentration of -one was 27.0%. (Yield 89.8%) The concentration of 4-hydroxy-4- (4-tetrahydropyranyl) -butan-2-one as a by-product is 1.4%, and the yield based on 4-tetrahydropyrancarbaldehyde Was 4.2%.
[0029]
Comparative Example 1
The same 49% aqueous solution of sodium acetoacetate as synthesized in Example 1 (176.7 g, 0.695 mol) was placed in a reactor having an internal volume of 1000 ml, and then 150 ml of toluene and 6.96 g (0.05 mol) of decahydroisoquinoline. And the pH was adjusted to 7.4 with concentrated sulfuric acid. 4-tetrahydropyran carbaldehyde 57.1g (0.5 mol) was dripped in this over 1 hour, Then, stirring was continued for 4 hours. During the reaction, the temperature was maintained at 20 to 25 ° C., and concentrated sulfuric acid was added dropwise to maintain the pH at 7.4 ± 0.1. After completion of the reaction, 80.0 g of water was added, and the temperature was raised to 65 ° C. with concentrated sulfuric acid at pH 1.5, and then the organic layer was separated from the aqueous layer. To the separated aqueous layer, 37.5 ml of toluene was added for extraction, and the organic layer was separated from the aqueous layer and then mixed with the first separated organic layer. After neutralizing the organic layer by adding 5.5 g of 25% NaOH aqueous solution, the organic layer was separated from the aqueous layer. Further, 10 g of water was added to the organic layer, and the mixture was stirred and washed with water. The organic layer was separated from the aqueous layer and then dried over anhydrous magnesium sulfate. After filtering off magnesium sulfate, 247.9 g of an organic layer was obtained. A part of the organic layer was sampled and analyzed by high performance liquid chromatography by an internal standard method using a standard product having a purity of 99.9%. As a result, the desired product 4- (4-tetrahydropyranyl) -3-butene-2 The concentration of -one was 24.9%. (Yield 79.9%) The concentration of by-product 4-hydroxy-4- (4-tetrahydropyranyl) -butan-2-one is 3.2%, and the yield based on 4-tetrahydropyrancarbaldehyde Was 9.1%.
[0030]
Example 3
109.1 g (0.417 mol) of a 47.4% aqueous sodium acetoacetate solution synthesized under the same conditions as in Example 1 using ion-exchanged water and NaOH adjusted to a concentration of 25% with reagent-grade NaOH have an internal volume of 1000 ml. Was added to an aqueous solution of iron (III) chloride containing 0.004 g (0.000075 mol) of iron ions. (The added iron ion corresponds to 0.025 mol per 1 mol of 4-tetrahydropyrancarbaldehyde), then 90 ml of toluene, 4.2 g (0.03 mol) of decahydroisoquinoline, 1.5 g of 85% phosphoric acid ( 0.015 mol) was added, and the pH was adjusted to 7.4 with concentrated sulfuric acid. 4-Tetrahydropyran carbaldehyde (34.2 g, 0.3 mol) was added dropwise thereto over 1 hour, and stirring was continued for 3 hours. During the reaction, the temperature was maintained at 20 to 25 ° C., and concentrated sulfuric acid was added dropwise to maintain the pH at 7.4 ± 0.1. After completion of the reaction, 48.0 g of water was added, the pH was raised to 1.5 with concentrated sulfuric acid and the temperature was raised to 65 ° C., and then the organic layer was separated from the aqueous layer. To the separated aqueous layer, 22.5 ml of toluene was added for extraction, and the organic layer was separated from the aqueous layer and then mixed with the first separated organic layer. The organic layer was neutralized by adding 1.8 g of 25% NaOH aqueous solution, and then the organic layer was separated from the aqueous layer. Further, 6 g of water was added to the organic layer, and the mixture was stirred and washed with water. The organic layer was separated from the aqueous layer and then dried over anhydrous magnesium sulfate. After magnesium sulfate was filtered off, 181.7 g of an organic layer was obtained. A part of the organic layer was sampled and analyzed by high performance liquid chromatography by an internal standard method using a standard product having a purity of 99.9%. As a result, the desired product 4- (4-tetrahydropyranyl) -3-butene-2 was obtained. -The concentration of ON was 21.3%. (Yield 83.7%) The concentration of by-product 4-hydroxy-4- (4-tetrahydropyranyl) -butan-2-one was 1.9%, and the yield based on 4-tetrahydropyrancarbaldehyde Was 6.7%.
[0031]
Comparative Example 2
177.6 g (0.695 mol) of 47.4% aqueous sodium acetoacetate solution synthesized under the same conditions as in Example 1 using NaOH adjusted to a concentration of 25% with ion-exchanged water and reagent-grade NaOH, with an internal volume of 1000 ml The iron (III) chloride aqueous solution containing iron ion 0.007g (0.000125mol) was added 1.0g. (The added iron ion corresponds to 0.025 mol per 1 mol of 4-tetrahydropyrancarbaldehyde). Then, 150 ml of toluene and 7.0 g (0.05 mol) of decahydroisoquinoline were added, and the pH was adjusted with concentrated sulfuric acid. It was set to 7.4. 4-tetrahydropyran carbaldehyde 57.1g (0.5 mol) was dripped in this over 1 hour, Then, stirring was continued for 4 hours. During the reaction, the temperature was maintained at 20 to 25 ° C., and concentrated sulfuric acid was added dropwise to maintain the pH at 7.4 ± 0.1. After completion of the reaction, 80.0 g of water was added, and the temperature was raised to 65 ° C. with concentrated sulfuric acid at pH 1.5, and then the organic layer was separated from the aqueous layer. To the separated aqueous layer, 37.5 ml of toluene was added for extraction, and the organic layer was separated from the aqueous layer and then mixed with the first separated organic layer. The organic layer was neutralized by adding 2.5 g of 25% NaOH aqueous solution, and then the organic layer was separated from the aqueous layer. Further, 10 g of water was added to the organic layer, and the mixture was stirred and washed with water. The organic layer was separated from the aqueous layer and then dried over anhydrous magnesium sulfate. After filtering off magnesium sulfate, 279.5 g of an organic layer was obtained. A part of the organic layer was sampled and analyzed by high performance liquid chromatography by an internal standard method using a standard product having a purity of 99.9%. As a result, the desired product 4- (4-tetrahydropyranyl) -3-butene-2 was obtained. The concentration of -one was 16.3%. (Yield 59.0%) The concentration of by-product 4-hydroxy-4- (4-tetrahydropyranyl) -butan-2-one was 6.9%, and the yield based on 4-tetrahydropyrancarbaldehyde Was 22.2%.
[0032]
【The invention's effect】
As described above, if the method of the present invention is used, the reaction proceeds without being suppressed by metal ions such as iron contained in the water used for the reaction, thereby suppressing the production of by-products. The target α, β-unsaturated ketone compound can be synthesized in a yield, and it is excellent as an industrial production method without problems in reaction operation such as liquid separation.

Claims (5)

Alkali metal salt or alkaline earth metal salt of acetoacetic acid in a mixed solvent of water and a poorly water-soluble organic solvent in the presence of a base and the general formula (I)
[Chemical 1]
R ¹ CHO
(In the formula, R ¹ is an optionally substituted alkyl group, an optionally substituted hydrocarbon group having a C3 or higher alicyclic skeleton, and a hydrocarbon having the alicyclic skeleton. alkyl group having a group, in a reaction of an aldehyde represented by the representative.) which may have a substituent multiple ring group, or a phenyl group which may have a substituent, suppressing the influence of iron ions for, phosphoric acid, 0.1～30Mol% relative aldehyde represented by at least one or more of the general formula selected from polyphosphoric acid and the group consisting of alkali metal salts or alkaline earth metal salt (I) General formula (II) characterized by adding
(In formula, R < ¹ > represents the same group as the above.) The manufacturing method of (alpha), (beta) -unsaturated ketone represented. The method for producing an α, β-unsaturated ketone according to claim 1 , wherein the base is an aliphatic secondary amine. The method for producing an α, β-unsaturated ketone according to claim 1 or 2 , wherein the pH is maintained within a certain range during the reaction. The range of pH is 6-8, The manufacturing method of the alpha, beta-unsaturated ketone of Claim 3 characterized by the above-mentioned. The method for producing an α, β-unsaturated ketone according to any one of claims 1 to 4 , wherein R ¹ in the general formula (I) has at least one substituent at the 1-position.