JPS5835501B2 - Method for synthesizing hydroxyalkyl-alkylene diaminoacetic acid and its salts as carbolic acid derivatives - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the synthesis of carbolic acid derivatives of hydroxyalkyl-alkylenediaminoacetic acids and their salts.

This carbolic acid derivative is one in which silver hydroxyamino acetate is bonded to an aromatic compound consisting of at least one carbolic acid group at a position ortho to the carbolic acid group,
It is a compound represented by the following general formula.

Here, the symbols R1 and R2 are -COOM or CH20H, and both may be -CH20H, but -COOM
It shouldn't be.

Moreover, symbols X1, X2, X3, and X4 are H or a lower alkyl group.

Furthermore, the symbol M is H, an alkali metal or an alkaline earth metal.

The compound represented by the above general formula has a strong tendency to form a metal chelate, and is extremely stable in an alkaline pH range, especially when it forms a chelate with trivalent iron ions (Fe+3).

The strong stability of this iron chelate is due to the presence in its structure of two carbolic acidic and alcoholic -OH groups, two amine N groups, and two carboxyl groups, which act as six-coordinated ligands. It's for ease.

This behavior of the above compounds provides certain benefits in agriculture.

That is, the above compounds can form soluble chelate compounds with iron and other stable metals even in calcareous soils.
It is useful for improving the deficiency of minority elements in plant cultivation.

According to the present invention, the above compound is synthesized by combining methylol derived from the sodium salt of hydroxyethyl-alkylenediaminodiacetic acid or dihydroxyethyl-alkylenediaminodiacetic acid with a carbolic acid-based compound in a mixed solvent of water and alcohol. This is done by reacting with a compound.

This carbolic acid compound is preferably one in which the para position to the hydroxyl group of carbolic acid is substituted with -CH3 in order to avoid possible formation of other compounds at the para position.

The reaction described here is expressed as follows.

At this time, the reaction temperature was maintained at 60°C to 100°C, and the PH
is adjusted to 8-11.

In this case, the reaction temperature is preferably 70°C to 80°C and the pH is 10 to 11, and an alkali is added if necessary.

The time required for this reaction varies depending on the carbolic acid compound used, but for example, when p-cresol is used as the carbolic acid compound, the reaction is carried out in a mixed solvent of methyl alcohol and water at its boiling point of about 80°C. If so, the above reaction will be completed in 3 hours.

In this case, if another alcohol with a high boiling point is used, the reaction temperature is adjusted to a temperature range of 60° C. to iooo° C. at the highest.

Furthermore, instead of the sodium salt of hydroxyethyl alkylene diaminoacetic acid used here, other alkali metal or alkaline earth metal salts can also be used, but the use of the sodium salt is still preferable.

The reason is that the final product of the sodium salt is
This is because it is difficult to dissolve in alcohol solvents and the product can be easily separated.

Furthermore, during the progress of the above reaction, the reacted product precipitates as crystals, making it somewhat difficult to control the reaction temperature.

Therefore, sufficient stirring is required during the reaction.

After the reaction is complete, the product is filtered and washed with methyl alcohol or inpropyl alcohol until no carbolic acid compounds or by-products generated during the reaction remain, and finally washed with acetone or inpropyl alcohol to facilitate drying. Washed with ether.

The yields of the final products obtained as described above are typical for condensates of this type and range from 65 to 70%, based on the hydroxyaminoacetic acid used.

The final product is a white crystal that dissolves in water in a slightly cloudy state, but is almost insoluble in alcohols and non-polar solvents.

Also, the final product does not exhibit a distinct melting point.

When combined with a trivalent iron salt, this compound exhibits a bluish-purple color in an acidic solvent, a reddish-purple color in a neutral solvent, and an orange color in an alkaline solvent.

Furthermore, this compound does not cause iron precipitation under any circumstances and is stable even at pH 14.

The reason why this product is stable even in such an alkaline pH range is due to the action of the two -OH1s present in the molecule, i.e., the carbolic acid -OH and the ethyl alcoholic -OH adjacent to the N of the amine. by.

The acid form of the product is obtained by adding a theoretical amount of mineral acid to an aqueous solution of the sodium salt and adjusting the pH of the acid to 3.4.

If it is necessary to isolate this product in acid form, the above pH 3,4 solution can be dried to dryness, preferably dehydrated under reduced pressure, extracted with warm ethyl alcohol and then cooled. lactic acid type crystals are obtained.

In order to obtain the hydroxyethyl-alkylenediaminoacetic acid used in this invention, a conventional method of amine carboxylation is followed.

That is, it can be obtained by adding hydrocyanic acid and bomaldehyde to mono- or di-hydroxyethyl alkylene diamine and reacting it to produce the corresponding mono- or di-nitrile, and then hydrolyzing it with an alkali or acid.

Another method for obtaining this aminoacetic acid is by treating the amine corresponding to the aminoacetic acid with 1 to 2 moles of a halogenated organic acid in an alkaline solvent.

However, in this method, in addition to the target aminoacetic acid, a mixture of amino acids and hydroxyethyl-
It is obtained depending on the number of N in the amine present in the alkylene diamine, and sodium salts corresponding to halogenated organic acids are also present.

In order to obtain a pure product, the method described above is used, that is, a method using a nitrile corresponding to the desired amine as a starting material and hydrolyzing it into a sodium salt or an acid.

In this case, the sodium salt of hydroxyethyl-alkylene diaminoacetic acid is also soluble in water, and a highly concentrated solution can be obtained without crystallization even in a mixed solvent of methyl alcohol and water.

This means that unreacted sodium salt of hydroxyethyl-alkylene diaminoacetic acid and unreacted carbolic acid can be dissolved in an extremely small amount of water, and the target carbolic acid derivative can be easily separated.

Example 1 1500 parts of methyl alcohol and 175 parts of 35% formaldehyde are added to 1000 parts of a 30% solution of the disodium salt of hydroxyethylethylenediaminodiacetic acid and the mixture is left at room temperature for 2-3 hours.

Then 100 parts of industrially pure para-cresol are added with vigorous stirring.

Thereafter, the pH of this solution is adjusted to 10.5 with 50% sodium hydroxide, and the whole is kept at about 80° C. and refluxed for 4-5 hours.

The reaction occurs rapidly while forming a white crystal precipitate.

After 4-5 hours, cool the whole and filter the solids,
The residue is washed repeatedly with isopropyl alcohol until completely white.

Finally, it is dried in a dryer at a temperature of 80 to 90°C.

The resulting product is (2-hydroxy-5-methylbenzyl)-ethylenediamine, N, hydroxyethyl N
', diacetic acid, or (2-hydroxy-5-methylbenzyl) N/, hydroxyethyl, ethylenediamine, the sodium salt of N-N' diacetic acid.

The yield of this product is approximately 282 parts.

In this case, the type of compound formed depends on the isomeric form of the hydroxyamino acid used.

The purity of the product produced by perchloric acid in acetic acid is 95%.
It was found that the degree of

The product can also be obtained in the form of the corresponding lactic acid by acidifying the pH to 3.4 or higher with sulfuric acid, extracting the dried residue with warm ethyl alcohol, and cooling the extracted product. .

The purity of this product was determined by 2
Nitrogen titration estimated 98.5%, and elemental analysis of the product showed a nitrogen content of 8.59%, which is in good agreement with the theoretical value of 8.70%.

Example 2 Using the dipotassium salt of hydroxyethyl-ethylenediaminodiacetic acid, which is two isomers of each other, Example 1
The reaction was carried out in the same manner as described in .

In this case, no precipitate was formed during the reaction, and no precipitate was formed even after cooling after the reaction was completed.

Also, the addition of an equivalent amount of inglobil alcohol is necessary to separate the reaction products.

This is because the dipotassium salt is more soluble in the mixed solvent of methyl alcohol and water than the sodium salt.

Depending on the structure of the hydroxyamino acid used, the dipotassium salt of (2hydroxy5methylbenzyl)-hydroxyethylethylenediaminodiacetic acid is obtained in either isomeric form.

The purity of the product obtained was 97.2% from titration of two nitrogens with perchloric acid in acetic acid solution, and elemental analysis of the product showed a nitrogen content of 6.53%. This is in good agreement with the theoretical value of 6.72%.

Example 3 2-4 dimethylphenol (asymmetric metaquidylole)
The reaction is carried out in the same manner as in Example 1.

The reaction product was formed similarly to Example 1, and according to the structure of the hydroxyamino acid used, the (2-hydroxy, 3-5 dimethylbenzyl) hydroxyethyl-ethylenediaminodiacetic acid salt was formed into two Formed in any of the isomeric forms.

The purity of the product obtained was 96.3% from titration of two nitrogens with perchloric acid in acetic acid solution, and elemental analysis of the product showed a nitrogen content of 6.77%. This is in good agreement with the theoretical value of 7.03%.

Claims (1)

[Claims] 1. In a mixed solvent of alcohol and water, 1 mole of an alkali salt of hydroxyethyl-alkylenediaminoacetic acid represented by the general formula is reacted with 1 mole of formaldehyde, and the reaction product methyl 1 mole of a carbolic acid compound represented by the general formula and a temperature range of 60°C to 1
A method for synthesizing a hydroxyalkyl-alkylenediaminoacetic acid and a hydrochloric acid derivative of a salt thereof having the general formula, characterized in that the reaction is carried out at 00°C and a pH range of 8 to 11. (However, the symbols R1 and R2 in each of the above formulas are -COOM or -CH20H, and both may be -CH20H, but cannot be -COOM. Xl, X2, X3, and X4 are H or lower It is an alkyl group. M is H, an alkali metal or an alkaline earth metal.)2 The carbolic acid compound is characterized in that the para position of the carbolic acid OH is substituted with -CH3. A method of synthesis according to claim 1. 3. The synthesis method according to claim 1 or 2, characterized in that a sodium salt of hydroxyethyl-ethylenediaminodiacetic acid is used as the alkali salt. 4. The synthesis method according to claim 1 or 2, characterized in that a sodium salt of dihydroxyethyl-ethylenediaminoacetic acid is used as the alkali salt. 5. The synthesis method according to claim 1, 2, 3, or 4, wherein the reaction temperature is maintained between 70°C and 80°C. 6 Reaction of the above methylol and carbolic acid compound※※1
The method of synthesis according to claim 1, 2, 3, 4, or 5, characterized in that the synthesis method is carried out in a pH range of 0 to 11.