JPH048425B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an improved method for producing N-acyl cyclic imine compounds. In general, N-substituted amide compounds have a good balance between hydrophilic and hydrophobic groups in the molecule, so they have good compatibility with various substances and have strong resistance to hydrolysis. Because of its excellent advantages, it is suitable for adhesives, paints, paper processing agents, textile processing agents, emulsions, urethane curing agents, pigment dispersants, plastic additives,
It is known to be applied to a wide range of fields such as polymer flocculants and ion exchange resins. It is also a useful compound as a raw material, intermediate, and product for compounds with complex structures such as pharmaceuticals, agricultural chemicals, amino acids, and natural products, and also as a raw material for amine production. However, since an inexpensive industrial production method for N-substituted amide compounds has not been established, they have not been used in large quantities. Conventionally, industrially used methods for producing N-substituted amide compounds include the reaction of a carboxylic acid chloride with an amine and the use of the Ritter reaction, but these methods are expensive. Alternatively, the types of compounds that can be produced are limited, and their applications are currently limited to specific fields. In addition, as a general method for producing N-substituted amide compounds, an amide compound is converted into an alkali metal-substituted amide compound by the action of a strong basic substance such as an alkali metal alkoxide, and then a halogen-substituted compound such as an alkyl halide is added to the amide compound. A method for producing N-substituted amide compounds is described, for example, in WJ
Reactions of Organic by Hickinbottom
Compounds 3rd edition, Longmans, Green and
Co. (1957) p. 344 and US Pat. No. 3,084,191. However, in these methods, the production process consists of two steps, a protic solvent such as liquid ammonia or alcohol, which is highly reactive with halogen-substituted compounds under a basic catalyst, and a protic solvent such as alcohol are used as the reaction solvent, and an alkali metal amide is used as the reaction solvent. There are various disadvantages such as the use of highly basic substances such as hydrogen compounds, alkoxides, etc., which are difficult to handle. Therefore, the yield of the desired product is low, the halogen-substituted compound to be reacted is not versatile, and all the desired products are N-monosubstituted amide compounds.
In addition, when producing N,N-disubstituted amide compounds, problems arise such as having to repeat the same production process, so it is not widely adopted industrially as a general method for producing N-substituted amide compounds. has not yet been reached. Furthermore, in recent years, GLIsele, A. Luttringhous,
As disclosed in Synthesis 1971(5), page 266, an amide compound and a basic substance are reacted in advance in an aprotic polar solvent to form an alkali metal-substituted amide compound, and then a halogen-substituted compound such as an alkyl halide is prepared. Two-step methods for producing N-alkyl substituted amide compounds are also known. However, even if such a method is adopted, satisfactory results have not been obtained. Furthermore, in USSR Inventor's Certificate No. 667547, in a method for producing N-alkylated organic compounds in a polar solvent, a basic substance such as caustic soda is added as an aqueous solution, and the basic substance starts the reaction in a liquid state. A method is disclosed in which the presence of water in the reaction mixture is said to be highly advantageous for the progress of the reaction. However, according to the research conducted by the present inventors, when using this method, the formation of side reactants is significant, and the desired N-
It has been found that the selectivity to substituted amide compounds is low, and the yield significantly decreases depending on the target N-substituted amide compound. In view of the actual situation regarding the production of the above-mentioned N-substituted amide compounds, the present inventors conducted intensive studies on the relationship between the amount of water present in the reaction system and the reactivity with the aim of improving the production method. The present invention was achieved by discovering that the influence on the selectivity toward substituted amide compounds, in other words, N-acyl cyclic imine compounds, is extremely large. In other words, the presence of water in the reaction system, which was previously thought to be advantageous,
Contrary to that estimate, side reactions occur and target N
-In order to inhibit the formation of acyl cyclic imine compounds and to suitably carry out the N-substitution reaction, the conventional method of reacting an amide compound with a strong basic substance and then reacting it with a halogen-substituted compound is not used. The present invention was achieved by discovering that it is necessary to simultaneously carry out a catalytic reaction of a strong basic substance, an amide compound, and a halogen-substituted compound. The present invention provides a method for producing an N-acyl cyclic imine by simultaneously contacting a strong basic substance, an amide compound, and a halogen-substituted compound in an aprotic polar solvent, in which a strong basic substance, an amide compound, and a halogen-substituted compound are brought into contact with each other in a suspension of the basic substance. It is characterized by starting. In the present invention, a specific method for starting the reaction while suspending a strong basic substance is a method of simultaneously supplying and mixing the three substances in an aprotic polar solvent to suspend the strong basic substance and causing the reaction. , a method in which a strong basic substance is suspended in an aprotic polar solvent, and then an amide compound and a halogen-substituted compound are simultaneously supplied and reacted, and a method in which an amide compound and a halogen-substituted compound are dissolved or An appropriate method may be employed, such as suspending and then adding and suspending a strong basic substance. The amide compounds that are the object of the present invention are broadly classified into monoamide compounds and polyamide compounds that are higher than diamide compounds. As monoamide compounds, aliphatic saturated carboxylic acid amide, aliphatic unsaturated carboxylic acid amide, aromatic carboxylic acid amide, alicyclic carboxylic acid amide,
These include urea and its derivatives. Aliphatic saturated carboxylic acid amides have the general formula C _o
It is a compound represented by H _2o+1 CONH ₂ , where n is an integer from 0 to 20. Also, nitro group, cyano group,
Those into which one or more types of substituents such as amino groups, carboxylic acid groups, sulfonic acid groups, alkoxy groups, and carboxylic acid ester groups are introduced are also targeted. Aliphatic unsaturated carboxylic acid amides have the general formula C _o
A compound represented by H _2o+1-2n CONH ₂ (in the formula, n is an integer of 2 to 20, m is an integer of 1 to 5), and has one or more carbon-carbon double bonds and/or triple bonds in the molecule. include. Also, nitro group, cyano group, amino group,
Those into which one or more types of substituents such as carboxylic acid groups, sulfonic acid groups, alkoxy groups, carboxylic acid ester groups, etc. have been introduced are also targeted. Aromatic carboxylic acid amide contains an aromatic ring in its molecule, and examples of the aromatic ring include a benzene ring, a naphthalene ring, an anthracene ring, and the like. Furthermore, one or more substituents such as a nitro group, cyano group, alkoxy group, amino group, carboxylic acid group, sulfonic acid group, carboxylic acid ester group, alkyl group, alkenyl group, or aryl group are introduced into the aromatic ring. It also includes compounds whose substituents or aromatic rings are bonded to aromatic rings such as ether groups, sulfone groups, and sulfide groups. Alicyclic carboxylic acid amides are compounds having an alicyclic structure in the molecule, and also include heterocyclic compounds composed of different elements. Moreover, urea and its derivatives are compounds having N-CO-N and N-CO-N-N atomic groups represented by urea. To illustrate the above-mentioned monoamide compounds, examples of the aliphatic saturated carboxylic acid amide include formamide, acetamide, propionamide, butyramide, pareramide, isovaleramide, pivalamide, lauramide, myristamide, palmitamide,
Examples include stearamide, methoxyacetamide, ethoxyacetamide, methoxypropionamide, ethoxypropionamide, cyanovaleramide, nitropropionamide, aminopropionamide, carbamoylpropanesulfonic acid, carbamoylpropanoic acid, and methyl carbamoylpropanoate. Aliphatic unsaturated carboxylic acid amides include, for example, acrylamide, methacrylamide, vinylacetamide, crotonamide, decenamide, nonadecenamide, propiolamide, butynamide, hexadiene carboxamide, pentinamide, heptinamide, ethoxyacrylamide, ethoxymethacrylamide, cyanobutenamide, nitrobutinamide, aminobutinamide, Carbamoyl propene These include sulfonic acid, carbamoyl crotonic acid, and methyl carbamoyl crotonate. Aromatic carboxylic acid amides include, for example, benzamide, naphthamide, anthracenecarboxamide, anthraquinonecarboxamide, biphenylcarboxamide, phenylacetamide, phenylpropionamide, phenyldecanamide, nitrobenzamide, nitronaphthamide, nitrosinnamamide, cyanobenzamide. , methoxybenzamide, ethoxybenzamide, methoxynaphthamide, N,N-dimethylaminobenzamide, N,
N-dimethylaminonaphthamide, carbamoylbenzenesulfonic acid, carbamoylnaphthalenesulfonic acid, toluamide, propylbenzamide, decylbenzamide, carbamoylnaphthoic acid, vinylbenzamide, allylbenzamide, butenylbenzamide, phenylcarbamoyl phenyl ether, vinylcarbamoyl phenyl ether ,
These include phenylcarbamoyl phenyl sulfone and phenylcarbamoyl phenyl sulfide. Examples of alicyclic carboxamides include cyclopropanecarboxamide, cyclobutanecarboxamide, cyclopentanecarboxamide, cyclopentenecarboxamide, cyclohexanecarboxamide, cycloheptanecarboxamide, cyclooctanecarboxamide, cyclooctenecarboxamide, pyrrolecarboxamide, furancarboxamide, thiophenecarboxamide, cyclohex Ruacetamide , cyclohexylpropionamide, pyridine carboxamide, pyrrolidine carboxamide, morpholine carboxamide, imidazole carboxamide, quinoline carboxamide and the like. Examples of urea and its derivatives include urea, biuret, thiobiuret, triuret, semicarbazide, carbonohydrazide, and carbazone. Among these amide compounds exemplified, unsubstituted amide compounds are preferred in that they allow the reaction to occur efficiently. More preferred are conjugated amide compounds in which the amide group of the amide compound is conjugated to a double bond, such as aliphatic unsaturated amide compounds such as acrylamide, methacrylamide, crotonamide, benzamide, tolylamide,
Examples include aromatic amide compounds such as isopropylbenzamide and naphthamide. On the other hand, the polyamide compounds include aliphatic saturated polycarboxylic acid amide, aliphatic unsaturated polycarboxylic acid amide, aromatic polycarboxylic acid amide, alicyclic polycarboxylic acid amide, and the like. Aliphatic saturated polycarboxylic acid amide has the general formula
It is represented by C _o H _2o-n+2 (CONH ₂ ) _n , where n and m are integers, n is 0-20, and m is 2-4. Furthermore, those into which one or more of a nitro group, a cyano group, an amino group, a carboxylic acid group, a sulfonic acid group, an alkoxy group, a carboxylic acid ester group, etc. are introduced are also targeted. Aliphatic unsaturated polycarboxylic acid amide has the general formula
C _o H _2o+2-n-2r (CONH ₂ ) represented by _n , where n, m and r are integers, n is 2 to 20, m is 2 to 4,
r is 1-4. Also, nitro group, cyano group,
Those into which one or more of amino groups, carboxylic acid groups, sulfonic acid groups, alkoxy groups, carboxylic acid ester groups, etc. have been introduced are also applicable. Aromatic polyvalent carboxylic acid amide contains an aromatic ring in the molecule, and examples of the aromatic ring include a benzene ring, a naphthalene ring, an anthracene ring, and the number of substitutions in the carboxylic acid amide is 2 to 6. Furthermore, one or more of a nitro group, a cyano group, an amino group, a carboxylic acid group, a sulfonic acid group, an alkoxy group, a carboxylic acid ester group, an alkyl group, an alkenyl group, an aryl group, etc. are introduced into the aromatic ring. Also included are compounds in which these substituents or aromatic rings are bonded to the aromatic ring via an ether group, sulfonic acid, sulfide group, etc. Alicyclic polyvalent carboxylic acid amide is a compound having an alicyclic structure in the molecule, and also includes a heterocyclic compound composed of different elements, and the number of substitutions in the carboxylic acid amide is 2 to 5. Next, to illustrate polyamide compounds, examples of aliphatic saturated carboxylic acid amides include oxamide,
malonamide, succinamide, glutaramide, adipamide, pimeramide, suberamide, azeramide,
Sebasamide, carbamoylmethylmethylglutaramide, butanetetracarboxamide, tetradecanedicarboxamide, octadecanedicarboxamide, methoxyadipamide, cyanoadipamide,
These include nitroadipamide, aminoadipamide, dicarbamoylbutanesulfonic acid, dicarbamoylbutanoic acid, dicarbamoylbutyl acetate, and the like. Aliphatic unsaturated polycarboxylic acid amides include, for example, maleamide, fumaramide, citraconamide, mesaconamide, decenedicarboxamide, tetradecenedicarboxamide, octadecenedicarboxamide, butenetetracarboxamide, hexadienedicarboxamide, pentynedicarboxamide, methoxybutenedicarboxamide , cyanobutine dicarboxamide, nitrobutene dicarboxamide, aminobutene dicarboxamide, dicarbamoylbutenesulfonic acid, dicarbamoylbutenoic acid, methyl dicarbamoylbutenoate, and the like. Examples of aromatic polyalboxylic acid amides include phthalamide, isophthalamide, terephthalamide, naphthalene dicarboxamide, anthracene dicarboxamide, anthraquinone dicarboxamide,
Biphenyldicarboxamide, phenylcitraconamide, naphthalenetricarboxamide, pyromellitutamide, nitrophthalamide, cyanophthalamide, aminophthalamide, methoxyphthalamide,
N,N-dimethylaminophthalamide, dicarbamoylbenzenesulfonic acid, dicarbamoylbenzoic acid, dicarbamoylbenzyl acetate, methylphthalamide, propylphthalamide, allyl phthalamide, phenyl dicarbamoyl phenyl ether, vinyl dicarbamoyl phenyl ether, These include phenyl dicarbamoyl phenyl sulfone and phenyl dicarbamoyl phenyl sulfide. Examples of alicyclic polycarboxylic acid amides include cyclopropanedicarboxamide, cyclopentanedicarboxamide, camphoramide, cyclohexanedicarboxamide, cyclohexanedicarboxamide, pyronedicarboxamide, pyridinedicarboxamide, and pyridinetricarboxamide. Among these amide compounds exemplified, unsubstituted amide compounds are preferred in that they allow the reaction to occur efficiently. More preferred are conjugated amide compounds conjugated to the double bond of the amide group of the amide compound, such as aliphatic unsaturated polyamide compounds such as fumaramide, maleamide, citraconamide, phthalamide, isophthalamide, terephthalamide, and benzene. Examples include aromatic polyamide compounds such as tolucarboxamide. Furthermore, examples of the dihalogen-substituted compound to be reacted with the amide compound include dihaloalkane compounds. Dihaloalkane compounds have the general formula X-(CH ₂
--) _o (X: halogen atom), where n is an integer from 2 to 5. Specifically, 1,2-dichloropropane, 1,4-dichlorobutane, 1,5-dichloropentane, 1,2-dibromoethane, 1,
3-dibromopropane, 1,4-dibromobutane, 1,5-dibromopentane, 1,2-diiodoethane, 1,3-diiodopropane, 1,4-
Examples include diiodobutane and 1,5-diiodopentane. By reaction with the above-mentioned halogen-substituted compound,
N-acyl-substituted imine compounds can be produced from dihaloalkane compounds, such as N-acylethyleneimine, N-acylazetidine, N-acylpyrrolidine, and N-acylpiperidine. The reaction solvent used in the present invention may be any aprotic polar solvent, such as acetonitrile,
Dioxane, nitromethane, nitroethane, nitrobenzene, pyridine, dimethoxyethane, tetrahydrofuran, tetrahydropyran, 2-
Methyl-tetrahydrofuran, benzonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, dimethylsulfoxide, N-methylpyrrolidone, hexamethylphosphoramide, sulfolane, oxepane, monoglyme, Grimes such as diglyme, triglyme, tetraglyme, tetramethylurea, tetraethylurea, 1,
3-dimethyl-2-imidazolidinone, 1,3-
Dimethyl-3,4,5,6-tetrahydro-2
Alkylureas such as (1H)-pyrimidinone, etc. can be used. Among the above-mentioned solvents, more suitable solvents include acetonitrile, N,N-
Dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, sulfolane, tetraglyme, 1,3-dimethyl-2-imidazolidinone, etc. can be used. Since these solvents generally have a strong affinity for water, care must be taken as water may be mixed in due to water absorption or water may be mixed in during circulation and reuse. In the reaction system of the method of the present invention, it is necessary to start the reaction in a state where at least a part of the strong basic substance is suspended, and the amount of water in such a state is equal to the amount of water in the reaction system. It is usually about 6% by weight. If the amount of water in this case exceeds this, side reactions such as hydrolysis of the halogen-substituted compound or amide compound are likely to occur, resulting in a significant decrease in yield. In order to carry out the reaction efficiently and increase the yield of the target product, the water content of the reaction system is preferably 5% by weight or less, more preferably
The content is preferably 2.5% by weight or less, particularly preferably 10,000ppm or less. The amount of the solvent to be used is not particularly limited, but is in the range of 5 to 95% by weight, preferably 10 to 90% by weight, based on the total amount of the reactants including the solvent. Next, the strong basic substance used in the present invention is a solid substance, and can be used as long as the pH of the aqueous solution when dissolved or suspended in water is 10 or more, preferably 11 or more. However, when using ion exchange resins and other ion exchangers, this condition does not apply, and this will be described later. Such strong basic substances include, for example, alkali metal oxides, alkaline earth metal oxides, alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal carbonates, alkali metal hydrides, and alkaline earth metal oxides. These include metal hydrides, alkali metal amides, alkali metal alkoxides, ion exchange resins, and other ion exchangers. To illustrate the above substances, examples of the alkali metal oxide include sodium oxide, potassium oxide, lithium oxide, rubidium oxide, and cesium oxide. Alkaline earth metal oxides are, for example,
These are beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, and barium oxide. Alkali metal hydroxides, such as sodium hydroxide, potassium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide. Examples of alkaline earth metal hydroxides include beryllium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, and barium hydroxide. Alkali metal carbonates are, for example, sodium carbonate, potassium carbonate, lithium carbonate, rubidium carbonate, and cesium carbonate. Examples of the alkali metal hydroxide include sodium hydride, potassium hydride, and lithium hydride. Examples of alkaline earth metal hydrides include beryllium hydride, magnesium hydride, and calcium hydride.
Alkali metal amides are alkali metal substituted compounds of ammonia, such as sodium amide, potassium amide, lithium amide, and the like. Alkali metal alkoxides are compounds in which the pronto of the hydroxyl group of alcohol is replaced with an alkali metal, and examples thereof include sodium methoxide, sodium ethoxy, sodium t-butoxide, potassium methoxy, potassium ethoxide, potassium t-butoxide, and the like. For the ion exchange resin, the OH type of a strong basic substance and the free type of a strong basic substance can be used, and the resin preferably has a water content of 15% or less. Other ion exchangers may be substances that exhibit an anion exchange phenomenon, such as anion exchange cellulose, anion exchange Cephadex, anion exchange liquid, basic dolomite, hydrated iron oxide, and hydrated zirconium oxide. You just need to be able to perform a sum reaction. Among the above-mentioned basic substances, those suitable for carrying out the method of the present invention are, for example, alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal oxides, alkaline earth metal oxides, alkali metal Carbonates, ion exchange resins, and other ion exchange resin bodies, and more suitable ones include, for example, alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal oxides, alkaline earth metal oxides, Alkali metal carbonates, ion exchange resins, and other ion exchangers. These strong basic substances are usually used in the reaction in solid form, and the reaction is initiated while at least a portion of them is suspended in the reaction solution. In carrying out the present invention, the relative usage amounts of the raw materials, amide compound, halogen-substituted compound, and strong basic substance, vary depending on the reactivity of the halogen-substituted compound and amide compound, etc., and cannot be definitively stated. The amount of the halogen-substituted compound to be used is 1.0 to 20 times the mole of the amide compound, preferably 1.5 to 15 times the mole, and the amount of the strong basic substance to be used is 1.5 to 20 times the mole of the amide compound, preferably 2.0～
The range is 1.5 times the mole. When using an unsaturated amide compound, it is preferable to add a polymerization inhibitor to prevent polymerization of raw materials and products during the reaction and purification steps. There are no particular restrictions on the polymerization inhibitor in this case, but
Common examples include phenolic inhibitors, amine inhibitors, mercaptan inhibitors, and copper powder. For the reaction method, a normal reaction vessel may be used, or if a strongly basic substance with low solubility is used, it is packed in a column and a mixed solution of an amide compound and a halogen-substituted compound is prepared. A flow type method in which the liquid is passed and circulated may also be used. However, a reaction vessel is more convenient for equipment maintenance and management. When manufacturing in a reaction vessel, there is no restriction on the order in which raw materials are added, but when using a highly reactive halogen-substituted compound, it is better to add the halogen-substituted compound last and allow the reaction to occur, since side reactions can be suppressed. It is convenient. The reaction temperature depends on the reactivity of the amide compound and halogen-substituted compound used, but if the reaction temperature is low, the reaction progresses slowly, while if the temperature is high, side reactions such as hydrolysis of the amide compound may occur and the product may deteriorate. Yield decreases. Therefore, the reaction is usually carried out at a temperature range of -20 to 100°C, preferably -10 to 70°C,
Particularly preferably, the temperature range is 0 to 50°C, except for specific halogen-substituted compounds. As long as it is within this temperature range, it is not necessarily necessary to keep the temperature constant during the reaction, but it is sufficient to monitor the progress of the reaction and appropriately set the reaction temperature to carry out the reaction efficiently. Further, the reaction time also varies depending on the amide compound and halogen-substituted compound used as well as the reaction temperature, but it is 30 hours at the longest, and usually within 10 hours. The progress of the reaction can be understood by observing changes in the properties of the reaction system and the concentrations of raw materials and target products in the reaction solution using gas chromatography or high performance liquid gas chromatography. After the reaction, by-produced metal chlorides are filtered off and distilled under reduced pressure using a conventional method to obtain a highly pure target product. However, if a metal chloride is dissolved in the reaction solution or if a sublimable raw material amide compound remains, after distilling off the solvent, use a solvent that forms two layers such as benzene-water or chloroform-water. After removing the above substances in combination, distillation under reduced pressure yields the desired product with high purity. Further, when the desired product has a high boiling point or is thermally decomposable, the desired product can be purified by methods such as solvent extraction and recrystallization. When the reaction solvent has a high affinity for water, such as dimethyl sulfoxide, and the target product is highly lipophilic, such as an N-alkyl substituted amide compound,
After the reaction, water is added to the reaction solution to separate the target product as an oil layer, or benzene, triene,
A method of extracting and separating the target product using a solvent that forms two layers with water, such as chloroform, can also be applied. According to the present invention, an extremely wide variety of N-substituted amide compounds having various functions can be produced in one step at low cost. In addition, it becomes possible to supply N-substituted amide compounds to a variety of uses that could not be applied conventionally. Furthermore, since the present invention uses the same reaction pattern, it is possible to produce a wide variety of N-substituted amide compounds in the same reactor, which has the advantage of being suitable for producing a wide variety of products in small quantities. Next, the present invention will be further explained by examples. Example 1 Production of N-acryloylpyrrolidine Acrylamide in 150ml of dimethyl sulfoxide
14g of potassium hydroxide and 38g of 1,4-dichlorobutane were added and stirred, and the reaction was carried out at 40°C for 4 hours. After the reaction, insoluble matter was filtered off, and the filtrate was distilled to 106-
A 108° C./10 mmHg fraction was collected, and 19 g of N-acryloylpyrrolidine was collected. Example 2 Production of N-methacryloylpyrrolidine 17 g of methacrylamide, 65 g of 1,4-dibromobutane and 0.05 g of phenothiazine were added to 150 ml of N,N-dimethylformamide, and 25 g of potassium hydroxide was gradually added while stirring in an ice bath. Added.
The reaction temperature was maintained at 10°C and the reaction was carried out for 6 hours. After the reaction, the insoluble portion was filtered off, the filtrate was distilled, and 110
A -111°C/15mmHg fraction was collected to obtain 23g of N-methacryloylpyrrolidine (yield: 82%). Examples 3 to 6 Reactions were carried out using the combinations of raw materials, strong basic substances, and solvents listed in Table 1 under the conditions listed in Table 1. In Examples 3 and 6 to 7, the reaction was carried out by adding 0.05 g of phenothiazine. After the reaction, treatment was carried out in exactly the same manner as in Example 2, and the products listed in Table 2 were separated under the distillation conditions listed in Table 2.

【table】

【table】

[Table] Example 7 Production of N,N'-carbonyl-dipyrrolidine Add 13 ml of urea to 150 ml of N,N'-dimethylformamide
96 g of 1,4-dibromobutane and 50 g of potassium hydroxide were added thereto, and the reaction was carried out at 20° C. for 4 hours. After the reaction, the insoluble part is filtered off, the filtrate and the filtrate are distilled, and the 38-
A 40°C/0.6 mmHg fraction was collected to obtain 29 g of N,N'-carbonyl-dipyrrolidine (yield 78%). Example 8 Production of N,N'-carbonyl-dipiperidine 1,3-dimethyl-2-imidazolidinone 150
13g of urea, 150g of 1,5-dibromopentane per ml
and 50 g of potassium hydroxide were added, and the reaction was carried out at 20° C. for 4 hours. After the reaction, the insoluble part is filtered off, and the solvent and
After distilling off the raw materials, the remainder is recrystallized to a melting point of 45-46℃.
33g of N,N'-carbonyl-dipiperidine
(yield 77%).

Claims (1)

[Scope of Claims] 1. A method for producing an N-acyl cyclic imine compound by simultaneously contacting and reacting a strongly basic substance, an amide compound, and a dihalogen-substituted compound in an aprotic polar solvent, wherein the base 1. A method for producing an N-acyl cyclic imine compound, characterized in that the reaction is initiated in the presence of a suspension of a cyclic imine compound. 2. The method according to claim 1, wherein the amount of water in the reaction system at the start of the reaction is 5% by weight or less.