JPH07309821A - Production of aliphaic polycarboxylic acid amide - Google Patents

Abstract

PURPOSE:To obtain a new trivalent or tetravalent aliphatic polycarboxylic acid amide which is a useful material as an antioxidant, ultraviolet absorbent, antibacterial agent, mildew-proofing agent, nucleating agent, additive to polymers, etc. CONSTITUTION:This compound is an aliphatic polycarboxylic acid amide expressed by formula I [A is a 3-10C aliphatic saturated carboxylic acid residue; X is NR<1>R<2> (R<1> and R<2> are each H, an alkyl, a halogenoalkyl,, an alkenyl, a cycloalkyl, a cycloalkenyl, an aryl or an aralkyl); (n) is 3 or 4], e.g. 1,2,3- propanetricarboxylic acid tricyclohexylamide. A compound of formula I is obtained by heating an aliphatic polycarboxylic acid ester of formula II (R<3> is a 1-4C alkyl) and an amine of formula III without using a catalyst or in the presence of an acid catalyst to carry out ester-amide interchange reaction. By this process, the objective compound is easily and efficiently produced on an industrial scale at a low cost in high yield and purity.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing novel aliphatic polycarboxylic acid amides. Such aliphatic polycarboxylic acid amides are useful materials as antioxidants, ultraviolet absorbers, antibacterial agents, antifungal agents, nucleating agents, polymer additives and the like.

[0002]

2. Description of the Related Art Amides of trivalent or tetravalent aliphatic polycarboxylic acids are compounds which have not been described in the literature, and their industrial production method is not known.

On the other hand, the following methods are known as methods for producing monocarboxylic acid amides and dicarboxylic acid amides. (A) A method of heating and dehydrating a carboxylic acid and amines. (B) A method by an ester / amide exchange reaction between a carboxylic acid lower alkyl ester and an amine in the presence of an alkali catalyst. (C) A method of reacting a mixed carboxylic acid anhydride with amines.

[0004]

DISCLOSURE OF THE INVENTION The present invention is industrially excellent in that it can produce novel and useful trivalent or tetravalent aliphatic polyvalent carboxylic acid amides under mild conditions with high purity and high yield. It is an object of the present invention to provide a manufacturing method.

[0005]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found the following facts, and have completed the present invention based on such findings.

(1) When a carboxylic acid amide is produced from a trivalent or tetravalent carboxylic acid as a raw material according to the above methods (a) to (c), decarboxylation is a side reaction in any method. , Intermolecular condensation, intramolecular and intermolecular imidization reactions occur, and in particular, almost no intended product can be obtained due to the intramolecular imidization reaction.

(2) However, by heating a predetermined carboxylic acid lower alkyl ester and an amine with or without a catalyst to carry out an ester-amide exchange reaction, the above side reaction is suppressed, and the yield is increased. The target product can be obtained well.

That is, the method for producing the aliphatic polycarboxylic acid amide represented by the general formula (1) according to the present invention is as follows. "The ester" and the amine represented by the general formula (3) (hereinafter referred to as "the amine") are heated in the absence of a catalyst or in the presence of an acid catalyst to cause an ester-amide exchange reaction. Is characterized by.

A (CO-X) n (1) [In the formula, A represents a linear or branched aliphatic saturated carboxylic acid residue having 3 to 10 carbon atoms. X is a group -NR ¹ R ²
Alternatively, it represents an N-containing saturated heterocycle. R ¹ and R ² are the same or different and each represents a hydrogen atom, an alkyl group, a halogenated alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group or an aralkyl group. Here, the cycloalkyl group, cycloalkenyl group, aryl group or aralkyl group is an alkyl group having 1 to 4 carbon atoms, or 1 to 4 carbon atoms.
The alkoxy group of 4 or halogen may be substituted. The number and position of such substituents are not particularly limited. n is an integer of 3 or 4. ]

A (COOR ³ ) n (2) [wherein A and n are as described in the general formula (1)]. R ³ represents an alkyl group having 1 to 4 carbon atoms. ]

X-H (3) [In the formula, X, R ¹ and R ² are respectively as described in the general formula (1). ]

As the aliphatic polycarboxylic acid amides which can be produced particularly efficiently by the method according to the present invention, in the group —NR ¹ R ² of the general formula (1), R ¹ or R ² is the same or different. , Hydrogen atom, alkyl group having 1 to 20 carbon atoms, halogenated alkyl group having 1 to 20 carbon atoms, and 3 to 20 carbon atoms
Alkenyl group, cycloalkyl group having 5 to 20 carbon atoms,
Cycloalkenyl group having 5 to 20 carbon atoms, 6 to 20 carbon atoms
The compound which is an aryl group or an aralkyl group having 7 to 20 carbon atoms is exemplified.

More specifically, in addition to unsubstituted amide (CO-X corresponds to CO-NH ₂ at this time), N-methylamide, Nn-hexylamide, Nn-octylamide, N -Cyclopentylamide, N-cyclohexylamide, N-4-methylcyclohexylamide, N-
N-monoalkyl (alkenyl) or aryl-substituted amides such as 2-methylcyclohexylamide, N-phenylamide, N-4-methylphenylamide, N-2,6-dimethylphenylamide, N, N-dimethylamide , N, N-diethylamide, N, N-di-n-propylamide, N, N-dicyclohexylamide, N, N-
Examples are compounds having groups such as N, N-dialkyl or aryl substituted amides such as diphenylamide.

The present esters are esters prepared by using a predetermined polyvalent carboxylic acid or its acid anhydride as an acid component and an aliphatic alcohol having 1 to 4 carbon atoms as an alcohol component.

Specific polycarboxylic acids include 1,2,
3-propanetricarboxylic acid, 1,3,5-pentanetricarboxylic acid, 1,2,3-butanetricarboxylic acid,
2,3,5-hexanetricarboxylic acid and 1,2,3
4-butane tetracarboxylic acid is illustrated.

Examples of the predetermined aliphatic alcohol include methanol, ethanol, n-propanol, isopropanol, n-butanol and isobutanol, among which methanol is recommended.

Specific examples of the esters include 1,2,
3-propanetricarboxylic acid trimethyl ester, 1,
2,3-propanetricarboxylic acid triethyl ester,
1,2,3,4-butanetetracarboxylic acid tetramethyl ester, 1,2,3,4-butanetetracarboxylic acid ethyl ester, 1,3,5-pentanetricarboxylic acid trimethyl ester, 1,3,5-pentane Examples thereof include tricarboxylic acid triethyl ester.

Examples of the present amines represented by the general formula (3) include a primary or secondary aliphatic, alicyclic or aromatic amine having a predetermined structure.

Examples of the aliphatic primary amine include methylamine, ethylamine, n-hexylamine, n-octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine and the like.
-Hexylamine, n-octylamine and the like are recommended.

Examples of the alicyclic primary amine include cyclopentylamine, cyclohexylamine, 2-methylcyclohexylamine, 4-methylcyclohexylamine and the like. Of these, cyclohexylamine, 2-methylcyclohexylamine and the like are recommended.

As the aromatic primary amine, aniline, 4
-Methylaniline, 2,4-dimethylaniline, 2,6
-Dimethylaniline, 2,6-dimethylaniline, p-
Examples thereof include methoxyaniline and p-chloroaniline, and among them, aniline and 2,6-dimethylaniline are recommended.

As the aliphatic secondary amine, dimethylamine, diethylamine, di-n-propylamine, di-n
-Butylamine, di-n-hexylamine and the like are exemplified, and among them, di-n-butylamine, di-n-hexylamine and the like are recommended.

Examples of the alicyclic secondary amine include dicyclopentylamine, dicyclohexylamine, dicycloheptylamine and the like, among which dicyclohexylamine is recommended.

As the aromatic secondary amine, diphenylamine, di (4-methyl) phenylamine, di (2,4-)
Examples thereof include dimethyl) phenylamine, and among them, diphenylamine and di (4-methyl) phenylamine are recommended.

Examples of the heterocyclic secondary amine include pyrrolidine, piperidine, morpholine and the like, and among them, pyrrolidine and piperidine are recommended.

The present amines are usually used in an amount of about 4 to 50 times, preferably about 4 to 15 times the molar amount of the present esters.

This reaction can be carried out in a solvent-free system, but since the target product can be easily isolated and purified, it is usually
It is carried out in an organic solvent.

As the organic solvent, cyclohexane,
Saturated hydrocarbons such as heptane, benzene, toluene,
Benzene hydrocarbons such as xylene, ethers such as dioxane, diglyme and anisole, N-methyl-2-pyrrolidone, N, N-dimethylacetamide,
A polar solvent such as dimethyl sulfoxide is used, and benzene hydrocarbons are particularly recommended.

The amount of the solvent is not particularly limited, but usually 0.1 to 10 times the weight of the present ester,
It is preferably used in an amount of about 0.5 to 5 times.

Further, an excess amount of the present amine itself may be used as a solvent instead of the above reaction solvent. The amount of the present amines used at this time is usually
It is about 10 to 50 times mol, preferably about 5 to 10 times mol.

The reaction temperature is usually about 100 to 300 ° C, preferably about 200 to 250 ° C. 100 ° C
If less than 300, the predetermined reaction hardly proceeds, while on the other hand
As a result of the intramolecular imidization reaction preferentially occurring at a temperature above 0 ° C, the yield of the desired product tends to be extremely low in any case.

The reaction is carried out for about 2 to 30 hours, preferably 1
It is completed by stirring for about 0 to 20 hours.

The reaction is preferably carried out in an atmosphere of an inert gas such as nitrogen or argon.

Although an acid catalyst such as tin oxide, tetra-n-butoxy titanate or tetra-iso-propoxy titanate can be used in the reaction,
The non-catalyst system is advantageous because it does not cause coloring of the product.

The amount of the acid catalyst used is 0.01 to 10% by weight, preferably 0.1 to 1% by weight, based on the present ester.
It is a degree.

The aliphatic polycarboxylic acid amides precipitated in the reaction system are filtered and then washed with an alcohol solvent such as methanol, ethanol or isopropanol or the alcohol / water mixed solvent to easily obtain a high-purity object. You can get things.

[0037]

The present invention will be described in detail below with reference to examples. It was confirmed by DI-MS and FT-IR that the reaction products in each example were the target amides.

EXAMPLE 1 21.8 g (0.1 mol) of 1,2,3-propanetricarboxylic acid trimethyl ester and 60.0 g (0.61 mol) of cyclohexylamine were placed in a 500 ml autoclave equipped with a temperature sensor and a stirrer. The mixture was charged and stirred at 220 ° C. for 6 hours. After cooling to room temperature, it was filtered, and the obtained white columnar solid was mixed with an isopropanol / water mixed solvent (3/1 =
The mixture was washed with 300 ml of v / v) at room temperature under stirring. After filtration, dry under reduced pressure at 120 ° C to obtain the desired 1, 2,
38.8 g (yield 92.6%) of 3-propanetricarboxylic acid tricyclohexylamide (white columnar solid) was obtained.

Example 2 As this amine, 2-methylcyclohexylamine 7
The same operation as in Example 1 was carried out except that 0.0 g (0.62 mol) was applied to obtain the target 1,2,3-propanetricarboxylic acid tri (2-methylcyclohexylamide).
(White columnar solid) 41.8 g (yield 90.7%) was obtained.

Example 3 The amount of cyclohexylamine was changed from 60.0 g to 24.4 g.
(0.25 mol) and 40 ml of toluene as a reaction solvent
In the same manner as in Example 1 except that the above compound was used, 38.4 g (yield 92.3%) of the target 1,2,3-propanetricarboxylic acid tricyclohexylamide was obtained.

Example 4 As this amine, 60.0 g of n-hexylamine
The same operation as in Example 1 was carried out except that (0.59 mol) was applied to obtain the desired 1,2,3-propanetricarboxylic acid tri (n-hexyl) amide (white solid) 40.7.
g (yield 97.1%) was obtained.

Example 5 The same operation as in Example 1 was carried out except that 60.0 g (0.65 mol) of aniline was applied as the present amines, and the target 1,2,3-propanetricarboxylic acid trianilide ( 34.3 g (yield 85.6%) of a white solid was obtained.

Example 6 As this amine, 80.0 g of di-n-butylamine
The same procedure as in Example 1 was performed except that (0.65 mol) was applied, and the target 1,2,3-propanetricarboxylic acid tetra (di-n-butyl) amide (white solid) 4.5
g (yield 80.0%) was obtained.

Example 7 The same operation as in Example 1 was carried out except that 60.0 g (0.85 mol) of pyrrolidine was applied as the present amines to obtain the desired 1,2,3-propanetricarboxylic acid tetrapyrrolidone. Ziramide (white solid) 32.0 g (yield 85.6)
%) Was obtained.

Example 8 As the present amines, 100 g of diphenylamine (0.5
9 mol) was applied and the same operation as in Example 1 was carried out,
Targeted 1,2,3-propanetricarboxylic acid tetra (diphenylamide) (white solid) 46.0 g (yield 6
0%).

Example 9 The same operation as in Example 1 was carried out except that 20.0 g (0.069 mol) of 1,2,3,4-butanetetracarboxylic acid tetramethyl ester was applied as the ester. 1,2,3,4-butanetetracarboxylic acid tetracyclohexylamide (white solid) (35.5 g, yield 92.3%) was obtained.

Example 10 The same as Example 1 except that 20 g (0.069 mol) of 1,2,3,4-butanetetracarboxylic acid tetramethyl ester and 70 g (0.62 mol) of 2-methylcyclohexylamine were used. The desired 1,2,3,4-butanetetracarboxylic acid tetra (2-methylcyclohexylamide) (white solid) (36.2 g, yield 87.5%) was obtained.

Example 11 The same procedure as in Example 1 was repeated except that the reaction temperature was 260 ° C.
3.60 g of the target 1,2,3-propanetricarboxylic acid tricyclohexylamide was obtained (yield 8.5.
%). Also, 20.0 g of amide imide was obtained as a side reaction product from the reaction mother liquor.

Example 12 The same procedure as in Example 1 was repeated except that the reaction temperature was 120 ° C.
3.60 g of the target 1,2,3-propanetricarboxylic acid tricyclohexylamide was obtained (yield 8.6
%).

Example 13 The same procedure as in Example 9 was repeated except that the reaction temperature was 260 ° C.
2.2 g (yield 5.6%) of the target 1,2,3,4-butanetetracarboxylic acid tetracyclohexylamide was obtained.

[0051]

EFFECTS OF THE INVENTION By applying the method of the present invention, the desired aliphatic polycarboxylic acid amides can be produced simply and efficiently in high yield and high purity under industrially useful conditions. it can.

Claims (2)

[Claims] 1. When producing the aliphatic polyvalent carboxylic acid amide represented by the general formula (1), the aliphatic polycarboxylic acid ester represented by the general formula (2) and the general formula (3) are used. A method for producing an aliphatic polyvalent carboxylic acid amide, which comprises heating an amine represented by the formula (3) with or without an acid catalyst to cause an ester-amide exchange reaction. A (CO-X) n (1) [In formula, A represents a linear or branched aliphatic saturated carboxylic acid residue having 3 to 10 carbon atoms. X is a group -NR ¹ R ²
Alternatively, it represents an N-containing saturated heterocycle. R ¹ and R ² are the same or different and each represents a hydrogen atom, an alkyl group, a halogenated alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group or an aralkyl group. Here, the cycloalkyl group, cycloalkenyl group, aryl group or aralkyl group is an alkyl group having 1 to 4 carbon atoms, or 1 to 4 carbon atoms.
The alkoxy group of 4 or halogen may be substituted. n is an integer of 3 or 4. ^{] A (COOR 3) n (} 2) [ wherein, A and n are as described in Formula (1). R ³ represents an alkyl group having 1 to 4 carbon atoms. ] X-H (3) [In formula, X, R < ¹ > and R < ² > are as respectively described in General formula (1). ] 2. The method for producing an aliphatic polycarboxylic acid amide according to claim 1, wherein the heating temperature is 200 to 250 ° C.