JPH07145122A - Process for producing N-alkyl-α, β-unsaturated carboxylic acid amide - Google Patents

Abstract

(57) [Summary] [Structure] An N-alkyl-β-alkylaminocarboxylic acid amide is produced from an α, β-unsaturated carboxylic acid ester and an aliphatic amine through the production of a β-alkylaminocarboxylic acid ester, Next, when the N-alkyl-β-alkylaminocarboxylic acid amide is decomposed to eliminate the aliphatic amine to produce an N-alkyl-α, β-unsaturated carboxylic acid amide, α, β-unsaturated It is characterized in that after the saturated carboxylic acid ester starts to be converted into the β-alkylaminocarboxylic acid ester, the reaction system is allowed to act with an alkali metal alcoholate as a catalyst. [Effect] According to this method, 100 ℃ or less and 2kg / cm
^{Even under} low temperature and low pressure reaction conditions such as ² G, N-
It is possible to obtain alkyl-α, β-unsaturated carboxylic acid amides in high yield.

Description

Detailed Description of the Invention

[0001]

The present invention relates to N-alkyl-α, β
-An improved process for the preparation of unsaturated carboxylic acid amides. N-alkyl-α, β-unsaturated carboxylic acid amides are coagulants, precipitants, adhesives, paper processing, resin modifiers,
It is a useful compound with a wide range of applications such as aqueous gels for fire protection glass.

[0002]

2. Description of the Related Art Conventionally, an α, β-unsaturated carboxylic acid ester is reacted with an aliphatic amine to give an N-alkyl-α,
Methods for producing β-unsaturated carboxylic acid amides have long been known. For example, K. Morsch, Monatsh. , 63, 220 (193
3) Or JG Erickson, J. Am. Chem. Soc., 74 , 6281 (1952)
The α, β-unsaturated carboxylic acid ester and the aliphatic amine are reacted in the absence of a catalyst to produce N-alkyl-β-
Synthesis of alkylaminocarboxylic acid amides
It is described that it can be produced by eliminating the amine of the molecule.

Further, in the presence of a catalyst, an α, β-unsaturated carboxylic acid ester is subjected to an addition reaction with an aliphatic amine to give a direct N 2
A method for producing an -alkyl-α, β-unsaturated carboxylic acid amide is also known, and as a catalyst used at that time,
In U.S. Pat. In the 949 publication, compounds of Ti, Zr, Hf, Pb, Zn and Ta are used.

[0004]

However, in any of the above-mentioned conventional manufacturing methods, all of the manufacturing steps, the purity of the obtained product, and the post-treatment steps are not always satisfactory. That is, K.
Morsch, Monatsh. , 63, 220 (1933) or JGErickson, JA
The method described in m.Chem.Soc., 74 , 6281 (1952) requires a high reaction temperature of about 150 to 250 ° C and a long reaction time, resulting in the formation of various by-products and high purity. Could not get the product. Furthermore, when an amine having a boiling point of 110 ° C. or less is used as a raw material, the pressure of the reaction system becomes about ² to 30 kg / cm ² G, and it is necessary to use a pressure resistant reactor during operation. It had the drawback of increasing costs.

Further, in the above-mentioned conventional methods using various catalysts, the total amount is not necessarily N-alkyl-due to the reaction between the α, β-unsaturated carboxylic acid ester and the amine.
Not converted to α, β-unsaturated carboxylic acid amide, but partially β-alkylaminocarboxylic acid ester or β-
The disadvantage is that it produces a mixture of alkylaminocarboxylic amides which must be separated. Further, the catalyst is relatively unobtainable and expensive, and further, after the reaction, a waste liquid containing a heavy metal is produced, and therefore, it is necessary to treat it environmentally.

Therefore, in the present invention, N-alkyl-α, β
-When manufacturing an unsaturated carboxylic acid amide, a target product can be obtained in a high yield even if it is operated at a lower temperature and a lower pressure, and further, it provides a manufacturing method which does not require particularly difficult post-treatment even after the reaction. The purpose is to

[0007]

[Means for Solving the Problems] In order to achieve the above object, the present inventors first described in US Pat. No. 3,288,794 or New Experimental Chemistry Lecture 14 [II] p.1148 (edited by the Chemical Society of Japan). The study was carried out in consideration of the method described, that is, it is possible to produce a carboxylic acid amide from a carboxylic acid ester and an amine in the presence of an alkali metal alcoholate. However, when an α, β-unsaturated carboxylic acid ester is amidated with an aliphatic amine by the method described in the above-mentioned literature, a polymerization reaction occurs with intense heat generation, or a β-alkylaminocarboxylic acid is generated. It only converts to an ester, and if it is heated further,
Almost no target N-alkyl-β-alkylaminocarboxylic acid amide could be obtained. why,
It is not clear at present whether the α, β-unsaturated carboxylic acid ester, when used as a raw material, is different from other carboxylic acid esters and exhibits particularly different properties. Formed a salt with β-unsaturated carboxylic acid ester or its polymer,
It is thought that it will be inactivated.

[0008] The inventors of the present invention continued to study the above. As a result, the α, β-unsaturated carboxylic acid ester and the aliphatic amine were once converted into a β-alkylaminocarboxylic acid ester, and then the reaction was carried out. Surprisingly, when an alkali metal alcoholate or a substance that forms an alkali metal alcoholate during the reaction is added to the system, 100
It was found that the N-alkyl-β-alkylaminocarboxylic acid amide can be obtained in good yield even under conditions of low temperature and low pressure such as temperature of not higher than 0 ° C and normal pressure, and completed the present invention.

That is, the present invention provides the general formula (1)

[Chemical 6] (In the formula, R ¹ represents hydrogen or a methyl group, and R ² represents an alkyl group having 1 to 8 carbon atoms.) And an α, β-unsaturated carboxylic acid ester represented by the general formula (2) 7)

Embedded image ^{R 3 -NH-R 4 (2} ) ( wherein, R ³ is hydrogen, an alkyl group, or an allyl group having 1 to 4 carbon atoms, R ⁴ is an alkyl group having 1 to 4 carbon atoms, An allyl group, a methoxypropyl group, a dimethylaminopropyl group, or a cyclohexyl group, and R ³ and R ⁴
May form a bond via a methylene group. ) And an aliphatic amine represented by the general formula (3)

[Chemical 8] (In the formula, R ¹ , R ² , R ³ , and R ⁴ are the same as above.) After the β-alkylaminocarboxylic acid ester represented by the formula (4)

[Chemical 9] (In the formula, R ¹ , R ³ and R ⁴ are the same as above.), An N-alkyl-β-alkylaminocarboxylic acid amide is produced, and then the N-alkyl-β-alkylaminocarboxylic acid is formed. The acid amide is decomposed to eliminate the aliphatic amine, and the general formula (5)

[Chemical 10] (In the formula, R ¹ , R ³ and R ⁴ are the same as above.) In producing the N-alkyl-α, β-unsaturated carboxylic acid amide, the compound represented by the general formula (1) Α represented by
The β-unsaturated carboxylic acid ester has the general formula (3)
An N-alkyl-characterized in that an alkali metal alcoholate is allowed to act on the reaction system after the conversion to the β-alkylaminocarboxylic acid ester represented by Chemical formula 8 is started.
This is a method for producing an α, β-unsaturated carboxylic acid amide.

The manufacturing method of the present invention will be described in detail below. Examples of the α, β-unsaturated carboxylic acid ester that can be used in the production method of the present invention include acrylic acid esters or methacrylic acid esters, and the alkoxy group in the α, β-unsaturated carboxylic acid ester is a methoxy group, Those which are an ethoxy group, a butoxy group, a 2-methylpropyloxy group and a 2-ethylhexyloxy group are preferably used. Generally, an easily available methoxy group is preferable, but in consideration of separating and recovering the amine after the reaction and reuse, it is possible to select a combination of alkoxy groups that can be easily separated from the amine. . That is, as an example, since a mixture of diethylamine and methanol is azeotropic, it is difficult to separate them from each other. Thus, for example, in the case of producing N, N-diethylaminocarboxylic acid amide, instead of using methyl α, β-unsaturated carboxylate, ethyl α, β-unsaturated carboxylate or α, β-unsaturated carboxylate is used.
It is considered economically advantageous to use unsaturated butyl carboxylate as a raw material.

As the aliphatic amine used in the production method of the present invention, aliphatic primary or secondary amines are used, such as methylamine, dimethylamine, ethylamine, diethylamine, propylamine, diamine. Examples thereof include propylamine, allylamine, diallylamine, methylethylamine, methylisopropylamine, methylbutylamine, isopropylamine, 3-methoxypropylamine, dimethylaminopropylamine, cyclohexylamine and piperidine. Among these, it is particularly preferable to use a secondary amine having low amidation reactivity such as dimethylamine, diethylamine, dipropylamine, or piperidine.

In the production method of the present invention, the α, β-unsaturated carboxylic acid ester and the aliphatic amine which are the raw materials can be usually used as they are as long as they are anhydrous products. Further, when these raw materials contain an acid component or water, the alkali metal alcoholate used in the reaction is likely to be deactivated, and therefore it is preferable to perform dehydration treatment in advance. Alternatively, it is possible to prevent the deactivation by a method in which a dehydrating agent is allowed to coexist in the reaction system during the reaction.

In the production method of the present invention, the feed ratio of the raw materials is preferably such that the aliphatic amine is used in excess of the required number of moles, and normally, 1 mole of the α, β-unsaturated carboxylic acid ester is mixed with the fatty acid. It is preferred to use 2 to 10 moles of group amine. If the amount of this aliphatic amine is less than 2 mol, the purity of the N-alkyl-β-alkylaminocarboxylic acid amide tends to decrease.

In addition, since α, β-unsaturated carboxylic acid ester is easily polymerized when the raw materials are fed, P-methoxyhydroquinone, phenothiazine, p-
It is preferable to add N-isopropylphenylenediamine or the like or two or more thereof in advance within a range of 1 to 50,000 ppm based on the weight of the α, β-unsaturated carboxylic acid ester.

In the production method of the present invention, in order to produce β-alkylaminocarboxylic acid ester, α, β-
It is possible by mixing the unsaturated carboxylic acid ester and the aliphatic amine in the above-mentioned range and reacting with stirring at a temperature of 10 to 110 ° C. for several tens of minutes or more. Also,
The pressure is usually sufficient even under normal pressure.

In the present invention, an alkali metal alcoholate is added to the reaction system as a catalyst during or after the conversion of the α, β-unsaturated carboxylic acid ester into the β-alkylaminocarboxylic acid ester. The timing of this addition may be immediately after the β-alkylaminocarboxylic acid ester begins to be formed, preferably 30% or more, more preferably 70%.
Above, particularly preferably, 90% or more is added after conversion to β-alkylaminocarboxylic acid ester. this,
When the α, β-unsaturated carboxylic acid ester is added all at once before the conversion starts, N-
It becomes difficult to obtain an alkyl-α, β-unsaturated carboxylic acid amide, and the object of the present invention cannot be achieved. Also,
Examples of the type of alkali metal alcoholate used include sodium methylate, sodium ethylate, potassium methylate, potassium ethylate, potassium t-butylate, and the like, and two or more of them may be used.
Further, in the present invention, not only the alkali metal alcoholate itself is used, but also a substance capable of generating an alkali metal alcoholate during the reaction may be used.
These include, for example, sodium hydride or metallic sodium.

The amount of alkali metal alcoholate used is
It is usually 0.00 relative to α, β-unsaturated carboxylic acid ester.
The amount is 01 to 2 equivalents, more preferably 0.001 to 0.5 equivalents, and particularly preferably 0.005 to 0.2 equivalents. If this amount is less than 0.0001 equivalent, it becomes very difficult to convert the β-alkylaminocarboxylic acid ester into the N-alkyl-β-alkylaminocarboxylic acid amide, and the reaction also requires a long time. Further, even if it is used in excess of 2 equivalents, there is no problem in the reaction, but it is uneconomical because it has no further effect. The above-mentioned addition of the alkali metal alcoholate may be carried out by adding a required amount all at once or by a method of gradually adding it. Further, in the above case, the raw material α,
When the β-unsaturated carboxylic acid ester and the aliphatic amine contain water or acid, it is desirable that the amount of alkali metal alcoholate used be larger than the total amount of water and acid.

In the method of the present invention, an N-alkyl-β-alkylaminocarboxylic acid amide is produced from a β-alkylaminocarboxylic acid ester by the action of the above-mentioned alkali metal alcoholate, and the reaction conditions in this case are usually It is sufficiently possible to carry out the treatment at a temperature of 10 to 110 ° C and under a reduced pressure or a spontaneously generated pressure of about ² kg / cm ² G. Further, in this case, a closed reactor or a reactor equipped with a reflux cooling device can be used, and the reaction time varies greatly depending on the raw materials used, so it is not mentioned here, but in general, Ranges from 1 to 100 hours. Further, in the present invention, if the boiling point of the aliphatic amine used is higher than that of the alcohol to be produced and does not form an azeotropic mixture, the reaction may be carried out while distilling the alcohol. It is possible.

As the reaction solvent, the reaction product itself can be used as a solvent, so that it is possible to add it without any particular addition. However, since the alkali metal alcoholate does not readily dissolve in the reaction product, an aliphatic alcohol having about 1 to 8 carbon atoms may be newly added. In this case, the amount of the alcohol added is 2 equivalents or less, preferably 0.5 equivalents or less, relative to the equivalent of the α, β-unsaturated carboxylic acid ester. Two
If it is added in excess of the equivalent amount, it becomes difficult to proceed the amidation reaction, which is not preferable.

After the N-alkyl-β-alkylaminocarboxylic acid amide is formed, the alkali metal alcoholate catalyst is neutralized with an acid, and then the low boiling point component is removed to obtain crude N
-Alkyl-β-alkylaminocarboxylic acid amide is obtained. In the neutralization in this case, the produced salt may be left as it is without being removed, or may be removed by filtration or washing followed by extraction. As the acid for neutralizing the alkali metal alcoholate, phosphoric acid, sodium dihydrogen phosphate, sulfuric acid, sodium hydrogensulfate, hydrochloric acid, acetic acid and the like can be used, and these may be an aqueous solution.

Next, the crude N-alkyl-β obtained above was used.
The -alkylaminocarboxylic acid amide can be subjected to thermal decomposition to obtain an N-alkyl-α, β-unsaturated carboxylic acid amide. Pyrolysis is usually at a pressure of 1
It can be performed under the conditions of Torr to atmospheric pressure and a temperature of 130 to 400 ° C., and can be performed by a general distillation procedure or a tubular flow reaction procedure. Also, when performing thermal decomposition,
As the polymerization inhibitor, it is preferable to add one or more of p-methoxyhydroquinone, phenothiazine, pN-isopropylphenylenediamine and the like in an amount of about 100 to 50,000 ppm.

N-alkyl-obtained by pyrolysis operation
The α, β-unsaturated carboxylic acid amide can be converted to a purified N-alkyl-α, β-unsaturated carboxylic acid amide by further performing a distillation operation to remove impurities.

[0023]

EXAMPLES Hereinafter, the production method of the present invention will be described in more detail with reference to examples. However, the manufacturing method of the present invention is not limited to those of these examples. In the following, "%" is on a molar basis unless otherwise specified, and
The analysis of each component in the reaction liquid and the product liquid was measured by gas chromatography.

Example 1 A 10 Lit. glass flask equipped with a reflux condenser was replaced with nitrogen, and 3300 g (45 mol) of diethylamine was added thereto at room temperature, 0.64 g of pN-isopropylaminophenylenediamine as a polymerization inhibitor, and methyl acrylate. 1320 g (15 mol) were fed in this order. In a nitrogen atmosphere, the temperature was raised to 60 ° C. under normal pressure, and the reaction was continued by stirring for 4 hours. The conversion rate of methyl acrylate to methyl β-N, N-diethylaminopropionate was 80%. Next, after cooling the reaction solution to room temperature, sodium methylate 77
g (1.4 mol) was added and the temperature was raised to 65 ° C in a nitrogen atmosphere.
The mixture was stirred under normal pressure reflux conditions for 46 hours. After cooling to room temperature, 115.3 g (corresponding to 1 mol) of 85 wt% phosphoric acid aqueous solution was added, and the mixture was stirred at 50 ° C. for 1 hour. The solid content was removed by filtration and then concentrated to obtain a crude product of N, N-diethyl-β-diethylaminopropionic acid amide. N, N-
The yield of diethyl-β-diethylaminopropionic acid amide was 92% based on the charged methyl acrylate. This crude N, N-diethyl-β-diethylamino-propionic acid amide was pyrolyzed at 100 Torr and 180 ° C. for 4 hours to obtain 1330 g of N, N-diethylacrylamide. The yield was 75% based on the charged methyl acrylate.

Example 2 A 3 Lit glass flask equipped with a reflux condenser was replaced with nitrogen, and at room temperature, 597 g (6.9 mol) of methyl acrylate containing 604 g (8.2 mol) of diethylamine and 100 ppm of p-methoxyhydroquinone. Were sent in this order. The temperature was raised to 50 ° C. under normal pressure, and the mixture was stirred for 4 hours, reacted, then concentrated and distilled, charged with β-N, N-diethylaminopropionate and charged at 90% yield based on methyl acrylate. Obtained. Next, β-N, obtained above,
To 64 g (0.4 mol) of methyl N-diethylaminopropionate, 44 g (0.8 mol) of diethylamine, 2.1 g (0.04 mol) of sodium methylate, and 16 g of methanol
(0.5 mol) were added respectively in this order, and stirring was continued under normal pressure reflux conditions for 39 hours to carry out a reaction to obtain N, N-diethyl-β-diethylaminopropionic acid amide. The yield was 70% on the basis of methyl β-N, N-diethylaminopropionate.

Example 3 A 3 Lit glass flask equipped with a reflux condenser was replaced with nitrogen, and at room temperature, 597 g (6.9 mol) of methyl acrylate containing 604 g (8.2 mol) of diethylamine and 100 ppm of p-methoxyhydroquinone. Were sent in this order. The temperature was raised to 50 ° C, stirring was continued for 4 hours, the reaction was allowed to proceed, concentration and distillation were carried out, and β-N, N-diethylaminopropionate methyl was charged, based on methyl acrylate.
Obtained in 90% yield. In a 1.5 Lit. glass autoclave, 320 g (2 mol) of methyl β-N, N-diethylaminopropionate obtained above and 292 g (4
Mol) and 11 g (0.2 mol) of sodium methylate are added respectively in this order, and the mixture is reacted under stirring at 100 ° C. for 8 hours,
N, N-diethyl-β-diethylaminopropionic acid amide was obtained. The reaction pressure generated in this case is 1.9 kg / cm
Was ² G. The yield of the obtained N, N-diethyl-β-diethylaminopropionate amide was 92% on the basis of methyl β-N, N-diethylaminopropionate.

Comparative Example 1 In Example 1, sodium methylate was added and reacted from the beginning. That is, sodium methylate, diethylamine, pN-isopropylaminophenylenediamine, and methyl acrylate were sequentially fed in the same amounts as those used in Example 1. As a result, there was a severe fever after 10 minutes. After the fever subsides, under normal pressure reflux conditions
It was stirred for 46 hours. N, N-diethyl-β-diethylaminopropionic acid amide was obtained in a yield of 3% based on methyl acrylate. Further, 48 g (1.5 mol) of methanol was added thereto, and the mixture was stirred for 12 hours under reflux under normal pressure. N, N-
The yield of diethyl-β-diethylaminopropionic acid amide based on methyl acrylate remained at 3%.

Comparative Example 2 A 1 Lit. glass flask equipped with a reflux cooling device was purged with nitrogen, and 330 g (4.5 mol) of diethylamine and 132 g (1.5 mol) of methyl acrylate were fed into the flask at room temperature. Without adding an alkali metal alcoholate, the mixture was stirred at 65 ° C. for 46 hours under a normal pressure reflux condition in a nitrogen atmosphere.
The yield of N, N-diethyl-β-diethylaminopropionic acid amide was 1% based on the charged methyl acrylate.

Comparative Example 3 1 Lit. An autoclave made of glass was purged with nitrogen, and 330 g (4.5 mol) of diethylamine and 1 g of methyl acrylate were added to the autoclave.
32 g (1.5 mol) were introduced. It stirred at 180 degreeC for 24 hours, without adding an alkali metal alcoholate. The reaction pressure generated at this time was 15 kg / cm ² G. In this case, the yield of N, N-diethyl-β-diethylaminopropionic acid amide was 84% based on the charged methyl acrylate.

Example 4 The same procedure as in Example 1 was carried out except that ethyl acrylate was used in place of methyl acrylate, and sodium ethylate was used in place of sodium methylate in the same mole numbers. As a result, the yield of N, N-diethyl-β-diethylaminopropionic acid amide was 87% based on the charged ethyl acrylate.

Example 5 A 1 Lit. glass flask equipped with a reflux condenser was replaced with nitrogen, and at room temperature 410 g (3.2 mol) of butyl acrylate containing 318 g (4.3 mol) of diethylamine and 15 ppm of p-methoxyhydroquinone. Sent in. In a nitrogen atmosphere, add 1.3 g (0.2 mol) of potassium hydroxide,
Stirring was continued under normal pressure reflux conditions for 10 hours to cause a reaction. After the solid content was removed by filtration, 1 g of sodium dihydrogen phosphate was added to this and distillation was carried out to obtain butyl β-diethylaminopropionate in a yield of 77% based on butyl acrylate. Next, 30 g of diethylamine was added to 0.82 g of sodium hydride (60% by weight) dispersed in mineral oil (equivalent to 0.02 mol).
(4.3 mol) and 40 g (0.2 mol) of butyl β-diethylaminopropionate obtained above were added, and the mixture was stirred for 27 hours under reflux under normal pressure. After cooling to room temperature,
1.5 g of a 85 wt% phosphoric acid aqueous solution (corresponding to 0.013 mol) was added, the temperature was raised to 50 ° C., and the mixture was stirred for 1 hour. Next, the solid content is removed by filtration, and then concentrated to obtain N, N-diethyl-β-
Diethylaminopropionic acid amide was obtained. The yield is 85% based on the charged butyl β-diethylaminopropionate.
Met.

Examples 6 to 11 By the same procedure as in Example 1, methyl acrylate was reacted with various amines to produce N-alkyl-β-alkylaminopropionic acid amides. In these examples, sodium methylate was added after more than 60% of the methyl acrylate had been converted to methyl β-N, N-diethylaminopropionate. The results are shown in Table 1. In addition, in Examples 8 and 9, the same flask as in Example 1 was used, and
Examples 6, 7, 10, and 11 were carried out using a glass autoclave or a stainless steel reactor. In Table 1, the number of equivalents of the catalyst is the number of equivalents of sodium methylate relative to the equivalent of charged methyl acrylate, and the product yield is the N-alkyl-β-alkylamino obtained based on the amount of charged methyl acrylate. This is the yield of propionamide.

[0033]

[Table 1]

Examples 12 to 16 In the same manner as in Example 1, using a stainless reactor, methyl methacrylate and various amines were reacted under pressure to obtain β-alkylaminopropionic amides. . The results are shown in Table 2. In these examples,
Sodium methylate was added after more than 60% of the methyl methacrylate had been converted to methyl β-alkylaminoisobutyrate. In Table 2, the equivalent number of the catalyst is the equivalent number of sodium methylate to the equivalent amount of methyl methacrylate charged, and the product yield is the N-alkyl-β-alkylamino obtained based on the methyl methacrylate charged. -Α
-Methylpropionic acid amide yield.

[0035]

[Table 2]

[0036]

According to the production method of the present invention, it has been impossible to produce an N-alkyl-β-alkylaminocarboxylic acid amide from an α, β-unsaturated carboxylic acid ester and an aliphatic amine, which has hitherto been impossible. It can be obtained in good yield even under the condition of low temperature and low pressure. That is, in Examples 1 to 16 carried out in the production method of the present invention, the reaction temperature was 40 to 10
At 0 ℃ and reaction pressure is atmospheric pressure or at best 1.9 kg / cm ² G
Moreover, it is possible to obtain a high yield of 70 to 94% under the conditions. On the other hand, in Comparative Example 1 in which the alkali metal alcoholate was added from the beginning and Comparative Example 2 in which the alkali metal alcoholate was not used, the yield was only a few%, and the alkali metal alcoholate was not used. To obtain the yield, as in Comparative Example 3, 180 ° C. and 15 kg
High temperature and high pressure conditions such as / cm ² G are required. Also,
In the production method of the present invention, the treatment of the alkali metal alcoholate after the reaction is easy and the environment is less polluted. Therefore, industrially N-alkyl-β
-In the production of an alkylaminocarboxylic acid amide,
The manufacturing method of the present invention can be preferably used.

Claims (4)

[Claims] 1. General formula (1) (Chemical formula 1) (In the formula, R ¹ represents hydrogen or a methyl group, and R ² represents an alkyl group having 1 to 8 carbon atoms.) And an α, β-unsaturated carboxylic acid ester represented by the general formula (2) 2) embedded image R ³ —NH—R ⁴ (2) (In the formula, R ³ represents hydrogen, an alkyl group having 1 to 4 carbon atoms, or an allyl group, and R ⁴ represents an alkyl group having 1 to ⁴ carbon atoms. Group, allyl group, methoxypropyl group, dimethylaminopropyl group, or cyclohexyl group, and R ³ and R ⁴
May form a bond via a methylene group. From an aliphatic amine represented by the general formula (3) (In the formula, R ¹ , R ² , R ³ , and R ⁴ are the same as above.) After the β-alkylaminocarboxylic acid ester is formed, the compound represented by the general formula (4) (Formula 4) ] (In the formula, R ¹ , R ³ and R ⁴ are the same as above.), An N-alkyl-β-alkylaminocarboxylic acid amide is produced, and then the N-alkyl-β-alkylaminocarboxylic acid is formed. The acid amide is decomposed to eliminate the aliphatic amine, and the general formula (5) (Chemical Formula 5) (In the formula, R ¹ , R ³ and R ⁴ are the same as above.) In producing the N-alkyl-α, β-unsaturated carboxylic acid amide, the compound represented by the general formula (1) Α represented by
The β-unsaturated carboxylic acid ester has the general formula (3)
N-alkyl-characterized in that an alkali metal alcoholate is allowed to act on the reaction system after the conversion to the β-alkylaminocarboxylic acid ester represented by the formula (3) is started.
A method for producing an α, β-unsaturated carboxylic acid amide. 2. An α, β-unsaturated carboxylic acid ester of 30.
The production method according to claim 1, wherein an alkali metal alcoholate is allowed to act in the reaction system after the conversion of at least% to β-alkylaminocarboxylic acid ester. 3. An α, β-unsaturated carboxylic acid ester 70
The production method according to claim 1, wherein an alkali metal alcoholate is allowed to act in the reaction system after the conversion of at least% to β-alkylaminocarboxylic acid ester. 4. The production method according to claim 1, wherein the aliphatic amine is dimethylamine, diethylamine, dipropylamine, or piperidine.