JPS603389B2 - Novel imidazole-allantoin adduct and its production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel imidazole-allantoin adduct and a method for producing the same, which is represented by the following general formula and is obtained by reacting an imidazole compound with allanthin.

[However, in the formula, R represents a substituent selected from the group consisting of a hydrogen atom, an 8-cyanethyl group, and an 8-[3,5-diamino-S-triazinyl-m]-ethyl group, and R2 represents a methyl group, an ethyl group, and R3 represents a substituent selected from the group consisting of phenyl groups, and R3 represents a substituent selected from the group consisting of hydrogen atoms and methyl groups. ] The imidazole compound in the present invention is represented by the following formula (i) to Q, and the compound represented by the formula The compound of formula {o) is obtained by dehydrogenating imidazoline obtained by the method described in JP-B-41-15171 or JP-B-39-126405, and the compound of formula {o) is Addition reaction of phenylimidazole and acrylonitrile (Sawa, Okamura: Nippon Kagaku Zasshi 9 Kagamigai No. 7 704-7
It is a compound obtained by the formula 1 and A
These two compounds are easily synthesized from the corresponding imidazole, acrylonitrile and dicyandiamide by the method described in Japanese Patent Publication No. 47-36391.

Formula {i} 2- Phenylimidazole formula (o} 1- (8-cyanethyl)-2-phenylimidazo --/
Formula 14-diamino-6-[2'methylimidazolyl m']
Ethyl-S-Formula 〇4-diamino-6-[2'ethyl-41'(5y-methylimidazolyl-m')]ethyl-S-triazine Allantoin, which is the other raw material in the present invention, is produced from uric acid or urea. It is an industrial chemical.

The present inventors were interested in the reaction between allantoin and various imidazole compounds, and as a result of extensive testing, we found that allantoin does not necessarily react with any imidazole compound to form a stable adduct as long as the partner is an imidazole compound. First, we discovered that a stable adduct can be selectively produced with respect to imidazole compounds, leading to the present invention.

That is, when various imidazole compounds were selected and investigated whether they gave an adduct of allantoin, it was found that the above formula 'A'
Although the imidazole compounds of .about. to .largecircle. can form stable adducts, none of the imidazole compounds shown below form adducts, indicating that allantoin has a kind of selectivity toward imidazole compounds.

2-methylimidazole 2-undecylimidazole 2-ethyl-4-methylimidazole 2-phenyl-4-methyl-imidazole 1-(8-cyanoethyl)-2-methylimidazole 2,4-diamino-6-[2-undecylimidazolyl[1] )′
] Ethyl-S triazine 1-(8-cyanoethyl)-2-ethyl-4(5) methylimidazole 1-(B-cyanoethyl)-2-undecylimidazole The imidazole-allantoine adducts of the present invention are all It is a new substance and has unique properties different from ordinary salts that can be understood in a general concept, and is extremely useful as an epoxy resin curing agent. It is attracting attention as a curing agent for forming one-component curable epoxy resin compositions because it significantly increases the pot life at room temperature and causes a rapid curing reaction by heating at a relatively low temperature of 90 to 150°C. It is something.

Characteristic properties of the imidazole-allantoine adduct of the present invention are as follows.

1. It is broken down into its constituent components in the usual TLC process.

2. It decomposes in certain solvents and separates into its constituent components.

It also decomposes when heated and separates into its constituent components. 3
．． It has a composition consisting of one molecule of imidazole and one molecule of allantoin.

4. It is stable in water, and most of the adducts can be recrystallized in water.

Especially the above 1. and 2. The properties suggest that imidazole and allantoine combine with an extremely weak bonding force to form the adduct.

From this point of view as well, it is different from ordinary salts, so it must be said that it is not an ordinary salt but a novel addition product. The adduct is produced by a heating reaction in a solution of the corresponding imidazole compound and an equimolar amount of allanthine, and is precipitated as colorless crystals by cooling the reaction solution.

If necessary, the precipitated crystals can be recrystallized for purification. The characteristics of the adduct of the present invention will be specifically explained below.

2-phenylimidazole-allantoine adduct
, Structural formula: Melting point: 150-1520 (partially decomposed) (W) Properties: Colorless crystals, weakly basic, soluble in water when heated TLC (Silica G, Et
OH, 12 color development): R〆0.75-0.65 (2-phenylimidazo-nole, R〆10.55-0.47 (allantoin) Infrared absorption spectrum: As shown in Figure 1.

According to this diagram, the spectrum is different from that of an equimolar mixture of 2-phenylimidazole and allantoin. M
ass spectrum (sample temperature 40℃, ionization chamber temperature 200℃, ionization energy 7&V, acceleration voltage 7KV)
): m/e144 (2-phenylimidazole), 11
7. M+ of allantoin and its fragment ions are not clear.

In addition, when the adduct was decomposed with an aqueous hydrochloric acid solution and allantoin was collected in a furnace, it showed an equimolar composition.

1-(8-Cyanethyl)-2-phenylimidazole-allantoine adduct Structural formula: Melting point: 109-110qC (decomposition) (W) Properties: Colorless crystals, weakly basic, soluble in water when hot TLC ( Silica G, EtO
H, 12 colors): R na 0. Total ~0.60 (imidazole compound) R〆0.55~0.47 (allantoin) Infrared absorption spectrum: As shown in Figure 2.

According to this diagram, the spectrum is different from that of an equimolar mixture of an imidazole compound and allanthin. Mass
Spectrum (sample temperature 40 ○, ionization chamber temperature 200
°C, ionization energy 7 degrees V, acceleration voltage 7KV): m
/el97 (imidazole compound), 157,143 (
2-phenylimidazole-H), 117,...7
& 77,...53 28...18 M↓ of furantoin and its fragmention are unclear.

In addition, the adduct was decomposed with an aqueous hydrochloric acid solution, and allantoin was collected in a furnace to confirm that it had an equimolar composition.

2,4-diamino-6-[2'methylimidazolyl(
1}']-Ethyl-S-triazine-allantoin adduct Structural formula: Melting point: 200-20〆0 (decomposition) (W) Properties: Colorless crystals, basic, soluble in water when hot TLC (Silica G, EtOH, 12 Color development): Rna 0.2
2-0.08 (imidazole compound) R〆0.54-0
．． 45 (allantoin) infrared absorption spectrum: As shown in Figure 3.

According to this diagram, the spectrum is different from that of an equimolar mixture of an imidazole compound and allanthine. MaSS
Spectrum (sample temperature 130:00, ionization chamber temperature 22:00
0oo, ionization energy 7 degrees v, acceleration voltage 7KV)
: m/e219 (imidazole compound), 138 (triazinylethyl), 138,125,109 95,8
2...Allantoin's M+ and its fragmention are unclear.

In addition, the compound was decomposed with an aqueous hydrochloric acid solution, and allanthin was collected in a furnace, and it was confirmed that the compound had an equimolar composition.

2,4-diamino-6-[2'ethyl-4'(5-somethyl-imidazolyl-river-ethyl-S triazine-allantoine adduct Structural formula Melting point: 195-1970 (decomposed) (W) Properties: Cool color Crystalline, basic, soluble in water when hot TLC (Silica G, EtOH "12 color development"): R〆0.3
2-0.10 (imidazole compound) Rna 0.55-0
．． 47 (allantoin) infrared absorption spectrum: As shown in Figure 4.

According to this diagram, the spectrum is different from that of an equimolar mixture of an imidazole compound and allantoin. Mass
Spectrum (sample temperature 110qo, ionization chamber temperature 24
500, ionization energy 7&v, acceleration voltage 7KV)
: m/e247 (imidazole compound), 218 13
8 (triazinylethyl),...110 (2-ethyl-4-methylimidazole)..."M10 of 2818 allantoin and its fragment ions are unclear.

Additionally, the adduct was decomposed with an aqueous hydrochloric acid solution, and allantoin was collected in a furnace to confirm that it had an equimolar composition.

Next, a method for producing the imidazole-allantoine adduct of the present invention will be explained.

The corresponding imidazole compound and allantoin in an amount equal to or less than the same mole are heated in a solvent at normal pressure at 100 q0 for about 1 hour, and then cooled and the precipitated crystals are collected in a furnace.

Water is most suitable as a solvent, and the amount used is preferably an amount that completely dissolves the reaction system, but there is no particular restriction thereto, and a smaller amount may be used. It is of course possible to perform the heating under pressure, but this is not very preferable because the equipment is expensive. If necessary, the furnace-collected crystals can be recrystallized and purified according to conventional methods. Water is suitable as the recrystallization solvent in this case. Example
21.6 ml (0.15 mol) of 12-phenylimidazole, 23.7 ml (0.15 mol) of allantoin, and 800 ml of water were poured into a concentrated solution and refluxed for about 1 hour (the contents were completely dissolved). ) "The contents were then cooled and the precipitated crystals were dried in a furnace to obtain 2-phenylimidazolelanthine adduct 32.
．． It took one evening.

Example 2 1-cyanoethyl-2-phenylimidazole 29.6
(0.15 mol), allantoin 23.7 mol (0.1
5 mol) and 800 mol of water were completely dissolved by heating in the same manner as in Example 1, the contents were allowed to cool, and the precipitated crystals were dried in a furnace to obtain 1-shanechyl-2-phenylimidazole. 41.5 days of roualanthine adduct was obtained.

Example 3 2,4-diamino-6-[2', methylimidazolyl-(1}')ethyl-S triazine 397.7 days (1.
82 mol), Allantoin 287 mol (1.82 mol) and water 1320 mol) at a temperature of 10,000 mol under the ocean.
The contents were heated for a period of time to completely dissolve the contents, and then the contents were cooled and the precipitated crystals were dried in a furnace to produce 2,4-diamino-6-[
482 2'methylimidazoIJ-[1'']ethyl-S-triazine-allantoine adducts were obtained.

Example 4 2,4-diamin-6-[2'ethyl-4'(5-methylimidazolyl[1}']ethyl-S triazine 697 moles (2.82 mol), allantoin 446 mole (2
．． 82 mol) and 4,520 mol of water on a table were heated under reflux for 1 hour to completely dissolve the contents, and then cooled.
The precipitated crystals were dried in a furnace to obtain 2,4-diamino-6-[2'
Chiru 41'・(5)'-Methylimidazolyru'1)
'] Ethyl-S triazine-allantoin adduct 5
It took 90 evenings.

[Brief explanation of the drawing]

1 to 4 show infrared absorption spectra of the imidazole-allanthine adduct of the present invention. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1 General formula ▲ Numerical formula, chemical formula, table, etc. ▼ [However, in the formula, R_1 is a hydrogen atom, β-cyanethyl group, and
)] - Represents a substituent selected from the group consisting of ethyl group, R_2 represents a substituent selected from the group consisting of methyl group, ethyl group and phenyl group, and R_3 represents a substituent selected from the group consisting of hydrogen atom and methyl group. Represents selected substituents. ] An imidazole-allantoin adduct represented by. 2. The additive according to claim 1, which is represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼. 3. The additive according to claim 1, which is represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼. 4. The additive according to claim 1, which is represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼. 5. The additive according to claim 1, which is represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼. 6 Formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ However, in the formula, R_1 is a hydrogen atom, β-cyanethyl group, and β-[3,5-diamino-S-triazinyl-(1)]
- represents a substituent selected from the group consisting of ethyl group, R
_2 represents a substituent selected from the group consisting of a methyl group, an ethyl group and a phenyl group, and R_3 represents a substituent selected from the group consisting of a hydrogen atom and a methyl group. ] It is characterized by reacting the imidazole compound shown by these with allantoin in a solvent. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [However, R_1, R_2 and R_3 in the formula are the same as above]
A method for producing an imidazole-allantoin adduct represented by 7. The manufacturing method according to claim 6, which uses water as a solvent.