JPH11100349A - Method for producing bis (hydroxymethyl) carboxylic acid - Google Patents

Abstract

The object of the present invention is to provide bis (hydroxymethyl)
An object of the present invention is to provide a method for producing an bis (hydroxymethyl) carboxylic acid by oxidizing an aldehyde with air or oxygen. The present invention relates to a compound represented by the general formula (I): Wherein R represents alkyl, cycloalkyl or phenyl, wherein the bis (hydroxymethyl) aldehyde represented by the general formula (II) is oxidized by air or oxygen. (Wherein R has the same meaning as defined above).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing bis (hydroxymethyl) carboxylic acid by oxidizing bis (hydroxymethyl) aldehyde with air or oxygen. Bis (hydroxymethyl) carboxylic acid, for example, 2,2-bis (hydroxymethyl) propionic acid, 2,2
2-Bis (hydroxymethyl) butyric acid is a compound useful as a raw material for high-value-added polymer materials such as water-soluble polyurethane.

[0002]

2. Description of the Related Art As a method for producing bis (hydroxymethyl) carboxylic acid, a method for oxidizing bis (hydroxymethyl) aldehyde using (a) hydrogen peroxide (US Pat.
3,312,736), and (b) a method using a compound such as cerium, titanium, zirconium, tin, niobium, molybdenum, and tungsten as a catalyst in an oxidation reaction using hydrogen peroxide (Japanese Patent Publication No. 7-45430). And (c) a method using perisobutyric acid [Journal of Synthetic Organic Chemistry,
36, 1095 (1978)] is known. Both methods use a peroxide such as hydrogen peroxide or a peracid as an oxidizing agent for bis (hydroxymethyl) aldehyde.

[0003] Peroxides such as hydrogen peroxide and peracid have high reactivity as oxidizing agents and are effective in many oxidation reactions. However, peroxides have the disadvantage that they are relatively expensive and can cause explosions due to overheating, friction and the like. For these reasons, it is generally desirable to use oxygen, which is cheaper and easier to handle, as an oxidizing agent, and furthermore, to utilize air.

[0004] In the production of bis (hydroxymethyl) carboxylic acid, there has been no report of a case where bis (hydroxymethyl) aldehyde was successfully used using oxygen or air as an oxidizing agent. Journal of Synthetic Organic Chemistry, 36, 1095 (1978
Years), bis (hydroxymethyl) aldehyde is the steric form of the two hydroxymethyl groups adjacent to the aldehyde.
Due to chemical factors, oxidation by air or oxygen, which is seen in simple aliphatic or aromatic aldehydes, does not proceed, and oxygen oxidation of bis (hydroxymethyl) aldehyde in ethyl acetate solution under ultraviolet irradiation A method for producing bis (hydroxymethyl) carboxylic acid has been reported, but the yield is as low as 11%, which is not satisfactory in practical use.

[0005]

An object of the present invention is to provide a method for producing bis (hydroxymethyl) carboxylic acid by oxidizing bis (hydroxymethyl) aldehyde with air or oxygen.

[0006]

The present invention relates to a compound of the formula (I)

[0007]

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Wherein R is alkyl, cycloalkyl,
Or, represents phenyl. Wherein the bis (hydroxymethyl) aldehyde represented by the formula) is oxidized with air or oxygen.

[0009]

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[0010] The present invention provides a process for producing a bis (hydroxymethyl) carboxylic acid represented by the formula: wherein R is as defined above.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the definition in the formula, alkyl represents a straight-chain or branched alkyl having 1 to 18 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-
Examples thereof include butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and octadecyl. Among them, alkyl having 1 to 5 carbon atoms is preferable, and ethyl is more preferable.

Cycloalkyl represents one having 3 to 8 carbon atoms, such as cyclopropyl, cyclobutyl,
Cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and the like can be mentioned. Hereinafter, the production method of the present invention will be described in detail. The bis (hydroxymethyl) aldehyde which is a raw material of the production method of the present invention has the general formula (III)

[0013]

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(Wherein R is as defined above), for example, propionaldehyde, n-butyraldehyde, or the like using a base catalyst in a known manner, for example, Volume 36, p. 1095 (1978
Year)) and by condensation with formaldehyde. The aldehyde represented by the general formula (III) can be purchased commercially or synthesized and obtained by a known method. Formalin is used as a formaldehyde source, but in other states,
For example, paraformaldehyde may be used. Examples of the basic catalyst include common basic inorganic compounds such as sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate, and triethylamine and tributylamine. Basic organic compounds are used. The amount of formaldehyde used is determined by the general formula (II)
It is preferable that the amount is 1 time (mole) or more with respect to the aldehyde represented by I). The bis (hydroxymethyl) aldehyde can also be produced by an addition reaction of α-alkylacrolein, for example, 2-ethylacrolein with formalin.

As the bis (hydroxymethyl) aldehyde used as a raw material for producing the bis (hydroxymethyl) carboxylic acid, the reaction solution obtained can be used as it is, but impurities such as unreacted raw materials are removed from the reaction solution. It is preferable to use it afterwards. As the bis (hydroxymethyl) aldehyde, for example, 2,2-bis (hydroxymethyl) propionaldehyde, 2,2-bis (hydroxymethyl) butyraldehyde and the like are preferably used.

Further, the bis (hydroxymethyl) carboxylic acid can be produced by oxidizing the bis (hydroxymethyl) aldehyde obtained as described above with oxygen or air. When oxidizing the bis (hydroxymethyl) aldehyde, it is preferable to use a reaction solvent, for example, an acetate such as ethyl acetate or butyl acetate, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, or n-butyl alcohol. , Lower alcohols such as isobutyl alcohol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone or water can be preferably used.

In the oxidation reaction, the reaction temperature is important, and the reaction temperature is preferably 40 to 100 ° C, more preferably 50 to 65 ° C. Further, the concentration of the bis (hydroxymethyl) aldehyde in the reaction solution is preferably 50% by weight or less,
It is more preferably at most 35% by weight. In the oxidation reaction, as a method for supplying oxygen, a method of dispersing air or oxygen at normal pressure in the reaction solution, or stirring the reaction solution in a pressure-resistant container under a normal pressure to pressurized air atmosphere, preferably under an oxygen atmosphere. Method and the like. When using air at normal pressure to pressurization, the oxygen partial pressure is preferably 0.2 atm or more.When using pressurized oxygen, it is necessary that the solution is sufficiently stirred. Important, oxygen pressure 1-5
It is preferably performed at atmospheric pressure.

It is preferable that oxygen or air is used in an amount equal to or more than the theoretical amount necessary for the oxidation of compound (I). After completion of the oxidation reaction, the obtained reaction solution may be concentrated, and the bis (hydroxymethyl) carboxylic acid may be crystallized and purified using an acetate such as ethyl acetate or a ketone such as acetone as a solvent.

The production method of the present invention is a method capable of producing bis (hydroxymethyl) carboxylic acid from bis (hydroxymethyl) aldehyde at low cost and safely because oxygen or air is used as an oxidizing agent.

[0020]

Next, embodiments of the present invention will be described in detail with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example 1 Oxidation of Crude 2,2-Bis (hydroxymethyl) butyraldehyde by Dispersing Oxygen into a Reaction Solution Reference Example 1 was placed in a glass reaction vessel equipped with a gas introduction tube.
The crude 2,2-bis (hydroxymethyl) butyraldehyde (10 g) and butyl acetate (30 g) obtained in the above were added, and the mixture was passed through a gas inlet tube at 0.5 ml / min of oxygen (normal pressure). The reaction was carried out at 6 ° C. for 6 hours. 2,2-oxidation products
The yield of bis (hydroxymethyl) butyric acid was determined by HPLC analysis (analysis conditions are shown below).
% Met. (HPLC analysis conditions) Column; Shodex Ionpak KC-811, 40 ° C. Mobile phase; 0.1 mM detection; Electrical conductivity detector

Example 2 Crude by Method Using Pressurized Oxygen
Oxidation of 2,2-bis (hydroxymethyl) butyraldehyde The crude 2,2-bis (hydroxymethyl) butyraldehyde obtained in Reference Example 1 (10 ml) was placed in a SUS316 pressure vessel (capacity: 100 ml).
g) and butyl acetate (5 g) were added and reacted vigorously under oxygen (5 atm) at 60 ° C. for 6 hours. As a result, the yield of 2,2-bis (hydroxymethyl) butyric acid was 65.7%. .

Examples 3 to 9 Reactions were carried out in the same manner as in Example 1 except that the reaction temperature was changed as shown in Table 1. Table 1 shows the reaction results.

[0024]

[Table 1]

Examples 10 and 11 The reactions of Examples 10 and 11 were carried out in the same manner as in Example 2 or 3, except that the oxygen pressure was changed as shown in Table 2. Table 2 shows the reaction results.

[0026]

[Table 2]

Examples 12 to 16 Reactions were carried out in the same manner as in Example 2 except that the reaction solvent was changed as shown in Table 3. Table 3 shows the reaction results.

[0028]

[Table 3]

Reference Example 1; 2,2-bis (hydroxymethyl)
Synthesis of Butyraldehyde A mixture of formalin (37%, 1000 g) and n-butyraldehyde (890 g) was vigorously stirred, and an aqueous sodium hydroxide solution (25%, 60 g) was added dropwise at room temperature to 60 ° C. over 30 minutes. Thereafter, stirring is continued for 1 hour. The resulting reaction solution was concentrated under reduced pressure to remove unreacted butyraldehyde, low-boiling by-products, and the solvent to obtain crude 2,2-bis (hydroxymethyl) butyraldehyde (about 45% by weight). .

[0030]

According to the present invention, there is provided a method for producing bis (hydroxymethyl) carboxylic acid by oxidizing bis (hydroxymethyl) aldehyde with air or oxygen.

Claims (7)

[Claims] 1. A compound of the general formula (I) Wherein R represents alkyl, cycloalkyl or phenyl, wherein the bis (hydroxymethyl) aldehyde represented by the general formula (II) is oxidized by air or oxygen. (Wherein R has the same meaning as described above). 2. The method according to claim 1, wherein in the general formulas (I) and (II), R is alkyl having 1 to 5 carbon atoms. 3. The method according to claim 2, wherein the alkyl is ethyl. 4. The reaction temperature for oxidizing bis (hydroxymethyl) aldehyde is 40 to 100 ° C.
The production method according to any of the above. 5. A method for oxidizing bis (hydroxymethyl) aldehyde, comprising: acetic acid ester, lower alcohol,
The production method according to any one of claims 1 to 4, wherein the production method is ketone or water. 6. The method according to claim 1, wherein the oxygen partial pressure in the case of using air for oxidizing bis (hydroxymethyl) aldehyde is 0.2 atm or more. 7. The production method according to claim 1, wherein the pressure of oxygen used for oxidizing the bis (hydroxymethyl) aldehyde is 1 to 5 atm or more.