JP2002088000A - Method for producing polyhydroxy compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and selectively produce a polyhydroxy compound by hydrating an epoxide without requiring a catalyst and a solvent. SOLUTION: This method for producing the polyhydroxy compound comprises hydrating the epoxide with water in the subcritical state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a simple and efficient method for producing a polyhydroxy compound.

[0002]

2. Description of the Related Art A polyhydroxy compound obtained by opening a ring of an epoxide by hydrolysis is a compound useful in the fields of cosmetics, chemicals, agricultural chemicals, pharmaceuticals and the like. In particular, terminal 1,2-diols obtained by hydrolyzing terminal epoxides such as α-olefin epoxides and glycidyl ethers are useful as nonionic surfactants, and their uses are diversified. Among them, glyceryl ether obtained by hydrolyzing glycidyl ether has extremely excellent performance as an emulsifier, a dispersant, and a detergent.

Since these epoxides generally have low solubility in water, several methods are known for efficient hydrolysis. Examples of the hydrolysis of glycidyl ether include (1) a method of hydrolyzing glycidyl ether in the presence of an acid or an alkali catalyst, and (2) tetrabutylammonium bromide in a solvent compatible with glycidyl ether and water. A method of hydrolyzing in the presence of a phase transfer catalyst, (3) a method of reacting a glycidyl ether with a carbonyl compound to form a 1,3-dioxolane compound, and hydrolyzing it, (4) a method of glycidyl ether and a lower fatty acid or acid anhydride. To form a glyceryl ester, which is then hydrolyzed.

However, for example, in the method (1), it is difficult to avoid side reactions such as polymerization between glycidyl ethers due to the inhomogeneity of glycidyl ether and water.
In the method of (3), it is necessary to consider the recovery of the solvent and the carbonyl compound, and in the method of (4), it is necessary to use an excess of lower fatty acid or acid anhydride in order to prevent the glycidyl ether from ring opening by glyceryl ether. And a large amount of fatty acids must be treated after the reaction.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a polyhydroxy compound efficiently and selectively by hydrolysis of an epoxide without necessarily requiring a catalyst or a solvent.

[0006]

SUMMARY OF THE INVENTION The present invention provides a method for producing a polyhydroxy compound which hydrolyzes an epoxide with water in a subcritical state.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The subcritical water (subcritical water) used for the hydrolysis of epoxide in the present invention refers to water under subcritical conditions, and here, a temperature of 250 to 350 ° C and a pressure of 4 ° C. It refers to water in the state of ~ 16.5MPa. Among these, the temperature is particularly preferably in the range of 270 to 330 ° C., and the pressure is preferably in the range of 6 to 13 MPa. Water in the subcritical state has a large decrease in dielectric constant, so epoxides that are insoluble in water at room temperature are considered to be easily dissolved, and the reactivity also increases, so the reaction proceeds even without a catalyst. it is conceivable that. However, the supercritical state (37
When the temperature is 2 ° C. and 22 MPa), decomposition of the main chain such as a hydrocarbon chain occurs, which is not preferable.

The epoxide used in the present invention includes an epoxide of a substituted olefin, a monohydric alcohol,
Di-, tri- or higher glycidyl etherified compounds, and general formula (1)

[0009]

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[Wherein, R represents a linear or branched alkyl group having 4 to 20 carbon atoms which may be partially or entirely substituted with a fluorine atom, or an alkylene oxide adduct thereof. Represents a methylene group or an oxygen atom. Α-olefin epoxide or glycidyl ether represented by the general formula (1) is particularly preferable.

Examples of the glycidyl ether compound of polyhydric alcohol include ethylene glycol diglycidyl ether,
Propylene glycol diglycidyl ether, butanediol diglycidyl ether, pentanediol diglycidyl ether, hexanediol diglycidyl ether, heptanediol diglycidyl ether, octanediol diglycidyl ether, nonanediol diglycidyl ether, decanediol diglycidyl ether, undecanediol Diglycidyl ethers of diols such as diglycidyl ether and dodecanediol diglycidyl ether and similar monoglycidyl ethers; mono-, di-, tri- or more glycidyl ethers such as glycerin and erythritol; As a linear or branched alkyl group having 4 to 20 carbon atoms represented by R in the general formula (1) of the terminal epoxide,
Butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl,
Hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group, 2-ethylhexyl group, 3,5,
A 5-trimethylhexyl group and the like and an alkylene oxide (ethylene oxide, propylene oxide and the like) adduct thereof can be mentioned. When the alkyl group is substituted with a fluorine atom, the degree of fluorine substitution and the substitution position are not particularly limited, and all can be preferably used. Preferred specific examples thereof include a nonafluorohexyl group, a hexafluorohexyl group, and tridecafluorooctyl. And perfluoroalkyl groups such as heptadecafluorooctyl group and heptadecafluorodecyl, and alkylene oxide adducts thereof.

In order to hydrolyze the epoxide with water in a subcritical state, the reaction between the epoxide and water may be performed under the above-mentioned subcritical conditions of water. Regarding the charging ratio of water to epoxide, water is preferably used in an amount of 2 to 100 moles, more preferably 5 to 20 times the mole of the epoxide.

Although this reaction proceeds without using a catalyst,
It is also possible to add an acid or an alkali as a catalyst.
In particular, when glycidyl ether is used as the epoxide, an alkali may be added to avoid the influence of a small amount of chloride which may be generally mixed into the raw material glycidyl ether. In this case, the alkali is preferably an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide, and the amount of addition is preferably a molar amount corresponding to the chlorine content of chloride.

Although this reaction does not necessarily require a solvent,
A solvent can be used depending on the properties of the raw material and the solubility in water. In this case, it is preferable to use a solvent having low reactivity with water.

The reaction mode in the present invention may be a batch type or a continuous type.

The polyhydroxy compound obtained as described above can be isolated and purified by known separation and purification means, specifically, distillation, washing, recrystallization, column chromatography and the like.

[0017]

EXAMPLES Example 1 15 g of octyl glycidyl ether in a 100 mL autoclave
(0.08 mol) and 30 g of water, immersed in a pre-heated tin bath, heated to 300 ° C (theoretical pressure 8.6 MPa),
The reaction was allowed to proceed for 3 minutes. After the reaction, it was rapidly cooled to about 80 ° C. After removing the aqueous layer, a small amount of a lower hydrocarbon component was removed, and the mixture was further washed with 20 mL of water to obtain 13.5 g of octyl glyceryl ether (83% yield). As a result of GC analysis, the raw material octyl glycidyl ether was all consumed. The reaction product had an octyl glyceryl ether purity of 96% and contained 4% of a by-product produced by reacting octyl glyceryl ether with octyl glycidyl ether.

Comparative Example 1 15 g of octyl glycidyl ether was placed in a 100 mL four-necked flask.
(0.08 mol), 30 g of water and 0.5 g of p-toluenesulfonic acid as a catalyst were charged and refluxed at 100 ° C. for 6 hours. After the reaction,
After cooling to 80 ° C., the aqueous layer was removed and washed with 20 mL of water. As a result of GC analysis, 99% of the raw material octyl glycidyl ether was consumed. The octyl glyceryl ether purity of the reaction product was 81%, and the generated octyl glyceryl ether contained 19% of a by-product which was reacted with octyl glycidyl ether.

Example 2 Using dodecane-1,2-epoxide as an epoxide, the reaction was carried out in the same manner as in Example 1, to obtain 15 g of dodecane-1,2-diol (yield 90%). As a result of GC analysis, all raw materials were consumed. The purity of the reaction product dodecane-1,2-diol is 97%, and the by-product of the reaction of dodecane-1,2-diol with dodecane-1,2-epoxide is 3%.
Contained.

[0020]

According to the present invention, desired polyhydroxy compounds such as 1,2-diols can be efficiently and selectively obtained without the need for a catalyst or a solvent. In particular, the hydrolysis of glycidyl ether proceeds in a very short time,
Glyceryl ether can be efficiently obtained with very few side reactions.

Claims (4)

[Claims] 1. A method for producing a polyhydroxy compound, wherein an epoxide is hydrolyzed with water in a subcritical state. 2. The method for producing a polyhydroxy compound according to claim 1, wherein the temperature in the subcritical state is 270 to 330 ° C. 3. An epoxide having the general formula (1): [In the formula, R represents a linear or branched alkyl group having 4 to 20 carbon atoms which may be partially or entirely substituted with a fluorine atom or an alkylene oxide adduct thereof, and X represents a methylene group. Or an oxygen atom. 3. The method for producing a polyhydroxy compound according to claim 1, wherein the compound is represented by the following formula: 4. The method for producing a polyhydroxy compound according to claim 3, wherein the epoxide is glycidyl ether (X in the general formula (1) is an oxygen atom).