JPH08176122A - Production of diguanamine - Google Patents

Abstract

PURPOSE: To obtain a diguanamine in high yield in a mild state without generating extreme heat by reacting a new monoguanamine with dicyandiamide under specific conditions. CONSTITUTION: A diguanamine of formula II [(4,6-diamino-1,3,5-triazin-2-yl) groups combine at 1,2-, 1,3- or 1,4-positions] is obtained by reacting a monoguanamine of formula I [(4,6-diamino-1,3,5-triazin-2-yl) group combines at 2-, 3- or 4-position] with dicyandiamide in the presence of a basic catalyst. An alkali metal, its hydroxide, an alkaline earth metal hydroxide, an amine, ammonia, etc., is used as the basic catalyst. The reaction is preferably carried out in a non-aqueous protic solvent or in an aprotic polar solvent. Further, the reaction is preferably carried out at 60-200 deg.C. This method can suppress the production of byproduct extremely, realizes simple production processes such as separation and purification of the products, and enables easy handling of the raw material.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a polymerizable monomer, a coating resin, an adhesive resin, a paper processing resin, a fiber processing resin, a powder coating resin, a building material, a molding material, a foam molding material, etc. Resin raw material, rubber material modifier, organic material flame retardant, guanamine compound derivative raw material, epoxy resin,
Curing agent such as urethane resin, stabilizer, compatibilizer, medicine,
Further, the present invention relates to a method for producing diguanamines, which are industrially useful compounds as agricultural chemicals.

[0002]

2. Description of the Related Art Conventionally, as a method for producing diguanamines, a method has been known in which a corresponding dinitrile compound and dicyandiamide are reacted at a reaction molar ratio of 1: 2 or more. Since such a method has a large reaction molar ratio of 2 or more, it is difficult to control the reaction system during the reaction, especially during the initial stage of the reaction, and the reaction system becomes extremely high in temperature, and the production of by-products is rapid enough not to be ignored. To significantly decrease the purity of the product, to easily cause such a state when using a dinitrile compound having a specific structure, when the reaction is carried out in a large excess molar ratio of dicyandiamide, unreacted dicyandiamide, etc. However, there is a defect that the recovery and purification steps such as the removal and separation of the product become complicated, and there are significant technical and economic restrictions.

[0003]

Means for Solving the Problems As a result of intensive studies on the production of guanamines, the present inventors have found that by reacting dinitrile having a specific structure with dicyandiamide under specific conditions, We have found that extremely useful novel monoguanamines can be produced selectively and in high yield. The present inventors have made extensive studies in view of the above defects in the method for producing diguanamines, and by performing a reaction under novel conditions with novel monoguanamines and dicyandiamide obtained based on the above findings. , It can be produced under mild conditions without significant heat generation, the production of by-products is remarkably small, diguanamines can be obtained in high yield, and the production can be easily performed such as a purification separation step. The present invention has been achieved by finding a manufacturing method having excellent characteristics such as easy handling of raw materials.

That is, the present invention provides (a) a compound of formula (1) (formula 3) in the presence of a basic catalyst.

Embedded image [In the formula, (4,6-diamino-1,3,5-triazin-2-yl)
The bonding position of the group represents 2-, 3-, or 4-position], and a monoguanamine compound represented by the formula (2) (Chemical Formula 4) is reacted with dicyandiamide.

[Chemical 4] [In the formula, (4,6-diamino-1,3,5-triazin-2-yl)
The bonding position of the group represents 1,2-, 1,3-, or 1,4-position], a method for producing a diguanamine, (b) a basic catalyst is an alkali metal, an alkali metal hydroxide And an alkaline earth metal hydroxide, an alkali metal alcoholate, an alkali metal salt of dicyandiamide, an alkaline earth metal salt of dicyandiamide, an amine, and ammonia. The production method described in (a), and (c) the reaction is carried out using at least one selected from the group consisting of a non-aqueous protic solvent and an aprotic polar solvent as a reaction solvent. ) Described in the manufacturing method,
(D) The method for producing according to any one of (a), (b) and (c) above, wherein the reaction is carried out at a temperature of 60 to 200 ° C.

In the method of the present invention, the monoguanamines represented by the formula (1) are represented by the formula (3)

Embedded image (In the formula, the bonding position of the cyano group represents the 1,2-, 1,3- or 1,4-position) and the dinitrile and dicyandiamide are expressed under specific conditions such as in the presence of a basic catalyst. However, the present invention is not limited thereto.

In the method for producing diguanamines according to the present invention, the reaction molar ratio between the monoguanamines represented by the above formula (1) and dicyandiamide can be appropriately selected within a relatively wide range. The reaction molar ratio of such monoguanamines and dicyandiamide is stoichiometrically 1: 1. However, when the molar ratio of dicyandiamide is made extremely small, the yield of the target diguanamines becomes low and the production efficiency becomes low. Deteriorate. Further, when dicyandiamide is used in a large excess, removal and separation of unreacted dicyandiamide becomes complicated, which is not preferable from a technical and economical viewpoint.

In order to improve the yield of diguanamines and to carry out the purification / separation process easily, the ratio of dicyandiamide to 0.3 to 5 mols, more preferably 0.5 to 2.0 mols, per mol of monoguanamines is preferred. The ratio is more preferably 0.7 to 1.8 mol, but can be appropriately selected depending on the production, purification, quality conditions and the like of the diguanamine.

Examples of the basic catalyst in the method for producing diguanamines according to the present invention include alkali metals such as potassium and sodium, alkali metals such as potassium hydroxide, sodium hydroxide, calcium hydroxide and barium hydroxide, and alkalis. Earth metal hydroxides, alkali metals such as potassium carbonate and barium carbonate, alkaline earth metal carbonates, potassium ethylates, alkali metal alcoholates such as sodium methylate, dicyandiamide alkali metals, alkaline earth metal salts, Piperidine,
Examples include amines such as ethylenediamine and pyrrolidone, and ammonia. In particular, alkali metal, alkali metal hydroxide, alkaline earth metal hydroxide, alkali metal alcoholate, alkali metal salt or alkaline earth metal salt of dicyandiamide, amines, and ammonia are preferable, and these are used alone or in combination of two or more. May be used. The amount of the catalyst added is not particularly limited, but is usually in the range of 0.001 to 500 mol% with respect to monoguanamines, more preferably from the viewpoint of production conditions and economy.
It is in the range of 0.1 to 300 mol%, and can be appropriately selected if necessary.

Further, in such a method for producing diguanamines, a method of using various solvents as a reaction solvent is very useful in order to carry out the reaction more smoothly,
Solvents that induce the formation of compounds other than the initial target compound and the reaction inhibition, such as fatty acids, the acid anhydrides, trifluoroacetic acid, liquid sulfur dioxide, sulfuryl chloride, mineral acids, and water are not preferred. As the reaction solvent, for example,
Alcohols such as methanol, ethanol, n-propanol, ethylene glycol, 2-methoxyethanol, 2-ethoxyethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, 1-methoxy-2-propanol, 1-ethoxy-2-propanol , Ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate and butyl acetate, ethers such as diethyl ether, dioxane and tetrahydrofuran, carboxylic acid amides such as N, N-dimethylformamide and N, N-diethylformamide, dimethyl Sulfoxides such as sulfoxides, sulfolanes such as sulfolane, methylamine, dimethylamine, trimethylamine, aniline, piperidine, pyridine, triethanolamine Amines such as, and and ammonia, in particular alcohols, amines, non-aqueous protic solvents, carboxylic acid amides such as ammonia, sulfolane, aprotic polar solvents such as sulfoxides are preferable. These solvents may be used alone, or may be a mixed system of two or more kinds such as a mixed solvent of ammonia and alcohol, dimethyl sulfoxide and cellosolves, etc., and may be appropriately selected as necessary. You can The water content of the reaction solvent used is preferably as low as possible, particularly preferably 1.0% by weight or less. In the method of the present invention, the reaction temperature is preferably 60 to 200 ° C, more preferably 80 to 180 ° C. If the reaction temperature is less than 60 ° C., the progress of the reaction is slow, a long time is required for the production, and the yield is lowered, which is not preferable. Also, 200
When the reaction temperature is higher than 0 ° C, the amount of by-products produced increases so rapidly that it cannot be ignored, the product purity is significantly lowered, and a complicated purification and separation step is required, which is not preferable.

Although the reaction system is not particularly limited, it can be carried out under normal pressure, under a naturally occurring pressure in a closed container, or under pressure, and can be appropriately selected as necessary.

In order to obtain the desired target compounds, diguanamines, from the reaction mixture of the above-mentioned reaction, it is possible to easily obtain the diguanamines by cooling the reaction solution and filtering out the crystallized diguanamines. However, the reaction mixture may be poured as it is into hot water for crystallization filtration. Unreacted dicyandiamide and monoguanamine associated with the crude diguanamine can be easily dissolved and fractionated from the crude diguanamine using a solvent such as hot water or methanol. Depending on the purpose of use, when further purification is required, the reaction solvent described above,
For example, alcohols, cellosolves, carboxylic acid amides, sulfolanes, sulfoxides, and the like, a method of performing recrystallization and dissolution fractionation with a mixed solvent of these solvents and water,
Dissolving in the above reaction solvent, pouring it into hot water for reprecipitation, dissolving the crude diguanamines in hydrochloric acid acidic aqueous solution, and mixing it with alkali to reprecipitate the diguanamines can be performed by it can.

However, according to the production method of the present invention, the diguanamines obtained by the reaction are made sufficiently pure by simply washing with an organic solvent such as methanol, water, or a mixed solvent thereof. Since it can be obtained, the above-mentioned purification method and the like are not always necessary.

[0013]

EXAMPLES Next, the present invention will be explained in detail by reference examples and examples. However, the description of these reference examples and examples does not limit the scope of the present invention thereto. In the following, dinitrile compounds were analyzed by gas chromatography, and dicyandiamide, diguanamines, monoguanamines, and reaction byproducts were quantified by liquid chromatography.

Reference Example 1 Production of Monoguanamines (1) In a 2 liter flask equipped with a stirrer, a thermometer, and a reflux condenser, 134.2 g (1.0 mol) of cyclohexanedicarbonitrile represented by the formula (3) and 75.7 dicyandiamide were used. g
(0.9 mol), caustic potash 8.4 g, methyl cellosolve 1000
ml was charged and gradually heated. The reaction liquid became transparent as the temperature increased, and the reaction rapidly proceeded when the temperature became close to 105 ° C., and the mixture was cooled appropriately and the internal temperature was controlled to 105 ° C. and stirred for 30 minutes. Furthermore, this solution is heated to a temperature of 105-110.
The reaction was carried out for 1 hour with stirring at ℃. Then, the reaction mixture was desolvated, 3 liters of deionized water was poured, the white precipitate was filtered off, the solid content was washed with deionized water, and dried under reduced pressure. Further, this solid content was recrystallized with a methanol-water solvent. The obtained solid content was dried under reduced pressure, and 2- (4,6-diamino-1,3,5-
Triazin-2-yl) -1-cyclohexanecarbonitrile, 3- (4,6-diamino-1,3,5-triazine-
2-yl) -1-cyclohexanecarbonitrile, and
A mixture of 4- (4,6-diamino-1,3,5-triazin-2-yl) -1-cyclohexanecarbonitrile was obtained. The results of elemental analysis of the target product are shown below. Elemental analysis CHN Measured value: 54.9% 6.6% 38.5% Calculated value: 55.03% 6.47% 38.50%

Example 1 A monoguanamine (1) obtained by the method of Reference Example 1 was placed in a 500 ml flask equipped with a stirrer, a thermometer and a reflux condenser.
After charging 89.4 g (0.41 mol), dicyandiamide 51.7 g (0.62 mol), potassium hydroxide 13.4 g (0.21 mol) as a basic catalyst, and methyl cellosolve 150 g as a reaction solvent at room temperature, the inside of the reactor was replaced with nitrogen. The mixture was gradually heated, the temperature was kept at 120 to 125 ° C., and the reaction was carried out for 3 hours while stirring. When the reaction solution was analyzed, the yield of diguanamine based on the charged monoguanamine was 98.0 mol%. Then, the reaction solution obtained above was transferred to a vacuum flask and heated at a pressure of 50 to 100 mmHg to recover 145 g of methyl cellosolve. In addition, the obtained white solid content is 1000
After washing with ml of deionized water and drying under reduced pressure,
Diguanamine with a purity of 99.9% was obtained. Table 1 shows the above results.

Examples 2 to 8 All were the same as in Example 1, except that the molar ratio of dicyandiamide to monoguanamine charged, the type of reaction solvent, and the reaction temperature were changed as shown in Table 1. Operated. As a result, diguanamine with a purity of 99.9% could be obtained in any of the examples. Table 1 shows the above results.

[0017]

[Table 1] (Note 1): The charged molar ratio of dicyandiamide to monoguanamine represented by the formula (1) is shown. (Note 2): It is based on the charged molar amount of monoguanamine represented by the formula (1).

Example 9 In a 500 ml flask equipped with a stirrer, a thermometer and a reflux condenser, 89.4 g (0.41 mol) of monoguanamine, 50.4 g (0.60 mol) of dicyandiamide, 12.9 g of sodium methylate as a basic catalyst, and As a reaction solvent, 150 g of dimethyl sulfoxide was charged at room temperature, the inside of the reactor was replaced with nitrogen, and the mixture was gradually heated to maintain the temperature at 120 to 125 ° C. and reacted for 3 hours while stirring. When the reaction solution was analyzed,
The yield of diguanamine based on the charged monoguanamine was 97.0 mol%. Then, the reaction solution obtained above was transferred to a vacuum flask and desolvated, the obtained white solid was washed with 1000 ml of deionized water, and dried under reduced pressure to obtain 99.9% pure diguanamine. It was

[0019]

According to the method of the present invention, highly pure diguanamine can be easily obtained from monoguanamine and dicyandiamide by a relatively easy operation.

Claims (4)

[Claims] 1. The formula (1) (formula 1) in the presence of a basic catalyst: [In the formula, (4,6-diamino-1,3,5-triazin-2-yl)
The bonding position of the group represents 2-, 3-, or 4-position], and a monoguanamine represented by the formula (2) (Chemical Formula 2) [In the formula, (4,6-diamino-1,3,5-triazin-2-yl)
The bonding position of the group represents the 1,2-, 1,3- or 1,4-position]]. 2. The basic catalyst is an alkali metal, an alkali metal hydroxide, an alkaline earth metal hydroxide, an alkali metal alcoholate, an alkali metal salt of dicyandiamide,
The method for producing diguanamines according to claim 1, which is at least one selected from the group consisting of alkaline earth metal salts of dicyandiamide, amines, and ammonia. 3. The reaction is carried out using at least one selected from the group consisting of non-aqueous protic solvents and aprotic polar solvents as a reaction solvent.
Alternatively, the method for producing a diguanamine according to 2 above. 4. The method for producing a diguanamine according to claim 1, wherein the reaction is carried out at a temperature of 60 to 200 ° C.