JPH1180186A - Production of alkylglycoside - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject compound useful as a surfactant low in skin irritativity in a state controlled in the condensation of a saccharide by reacting a higher alcohol with the saccharide in the presence of a specific aluminum compound as an acid catalyst. SOLUTION: This method for preparing an alkylglycoside comprises reacting a higher alcohol (e.g. decyl alcohol) with a saccharide (e.g. glucose) in the presence of an aluminum compound of the formula R<1> is a (substituted) hydrocarbon group, a (substituted) hydrocarbonoxy group; (l), (m), (n) are each an integer wherein at least one of (l) and (n) is not zero, and (l)+(m)+(n)=3} as an acid catalyst, while controlling the self-condensation of the saccharide. Thus, the objective alkylglycoside useful as a surfactant low in skin irritativity, a foam stabilizer for anionic surfactants, and the like is obtained in an improved yield.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an alkyl glycoside, and more particularly, to a method for producing an alkyl glycoside which is excellent in economical efficiency by using a specific catalyst to suppress the condensation between sugars or the resulting alkyl glycoside and the sugar. It relates to a manufacturing method. In particular, the present invention relates to a method for producing an alkyl glycoside having 8 to 14 alkyl carbon atoms having a degree of condensation of a sugar skeleton of 1 to 1.4.

[0002]

2. Description of the Related Art Alkyl glycosides are surfactants having low irritation to the skin, and not only generate stable foams per se, but also act as foam stabilizers for anionic surfactants. Are known. For these reasons, alkyl glycosides have been attracting attention with the recent commercialization.

One of the general methods for producing an alkyl glycoside is a method in which a sugar constituting the alkyl glycoside is directly reacted with a higher alcohol having 8 or more carbon atoms in the presence of an acid catalyst (hereinafter referred to as a "direct method"). ), And numerous inventions have been made in this regard (US Pat. No. 3,839,318). However, in such a direct method, when sugar, water and an acid catalyst coexist, sugars are condensed to form by-products such as highly condensed products (hereinafter referred to as "polyalkyl glycosides").
It is not preferable because the yield is reduced and the hue is deteriorated.
In particular, when the saccharide is a monosaccharide, the produced alkyl glycoside and the monosaccharide may be condensed, and the yield is significantly reduced.

[0004] As a method for suppressing condensation between sugars or between a formed alkyl glycoside and a sugar (hereinafter referred to as "sugar condensation") and obtaining a desired alkyl glycoside in high yield, a higher alcohol is used in excess of the sugar. Is generally known (for example, JP-A-59-5199).

[0005]

However, in such a method, an operation for removing unreacted excess alcohol from the crude reaction product is required, and deterioration of odor and the like may occur at the stage of this operation. In addition, it is not necessary to use a solvent because alcohol is used in excess, but there is a problem in terms of economic efficiency such as a remarkable decrease in productivity. Further, there is a problem that when the conversion rate of the sugar increases and the concentration of the alkyl glycoside in the system increases, the degree of sugar condensation rapidly increases.

[0006] Therefore, the present invention suppresses the saccharide condensation,
An object of the present invention is to provide a method for producing an alkyl glycoside having an improved yield by promoting the condensation of an alcohol and a saccharide.

[0007]

Means for Solving the Problems Accordingly, the present inventors have:
As a result of intensive studies to achieve the above object, it has been found that an aluminum compound represented by the following general formula (1) can suppress saccharide condensation as an acid catalyst used in the reaction. Furthermore, it has been found that the same effect can be obtained by using two kinds of (A) aluminum alkoxide and (B) phenols or sulfonic acids represented by the following general formula (2) together as an acid catalyst. The invention has been completed.

That is, a first invention of the present invention relates to a method for producing an alkyl glycoside from a higher alcohol and a saccharide, the method comprising the following general formula (1):

[0009]

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(Wherein, R ¹ represents a hydrocarbon group which may have a substituent, and R ² represents an oxygen atom, a chlorine atom, a hydrocarbon group which may have a substituent or a substituent. And R ³ represents an aromatic hydrocarbon oxy group which may have a substituent, and l, m,
n is such that at least one of l and n is not 0, and l + m +
Indicates a number where n = 3. The present invention provides a method for producing an alkyl glycoside, which comprises using an aluminum compound represented by the formula (1) as an acid catalyst.

In a second aspect of the present invention, there is provided a method for producing an alkyl glycoside from a higher alcohol and a saccharide, wherein (A) an aluminum alkoxide and (B) a phenol or a compound of the general formula (2)

[0012]

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(Wherein, R ¹ has the same meaning as described above.)
And a method for producing an alkyl glycoside characterized by using a sulfonic acid represented by the formula (1) in combination.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION As the higher alcohol used in the present invention, a linear or branched saturated or unsaturated alcohol having 8 to 22 carbon atoms or an alkylene oxide adduct thereof is preferably used. In particular,
Octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, heptadecyl alcohol, octadecyl alcohol, nonadecyl alcohol, eicosyl alcohol, oleyl alcohol, Alternatively, ethylene oxide adducts, propylene oxide adducts, and the like thereof may be mentioned, and among them, alcohols having 8 to 14 carbon atoms are particularly preferable.

As the saccharide used in the present invention, any of monosaccharides, oligosaccharides and polysaccharides can be used.
Examples of the monosaccharides include, for example, allose, artose, glucose, mannose, growth, idose, galactose, talose, ribose, arabinose, xylose,
Aldoses such as lyxose and the like, oligosaccharides include maltose, lactose, sucrose, maltotriose and the like, and polysaccharides include hemicellulose, inulin, dextrin, dextran, xylan, starch, hydrolyzed starch and the like. Is mentioned. Of these, preferred are monosaccharides having 6 or less carbon atoms,
Glucose is particularly desirable.

In the general formula (1) or (2), examples of the optionally substituted hydrocarbon group represented by R ¹ or R ² include a hydroxyl group, an alkoxyl group and a halogen atom. An alkyl group or an alkenyl group which may be substituted; an alkyl group, a hydroxyl group, an alkoxyl group or an aryl group which may be substituted by a halogen atom. Here, examples of the alkyl group which may be substituted with a hydroxyl group or the like include, for example, those having 1 to 3 carbon atoms.
6 linear or branched alkyl groups, specifically methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl , Tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, 2-ethylhexyl, 3,5-dimethylhexyl, etc. No. Examples of the alkenyl group which may be substituted with a hydroxyl group or the like include, for example, those having 2 to 36 carbon atoms.
Straight-chain or branched-chain alkenyl groups such as vinyl group, propenyl group, oleyl group, linole group and the like, and those substituted with hydroxyl groups and the like. Examples of the aryl group which may be substituted with an alkyl group include a phenyl group, a naphthyl group and the like, and those substituted with these alkyl groups. Examples of the alkoxyl group which may have a substituent include, for example, a linear or branched alkoxyl group having 1 to 36 carbon atoms, and specific examples thereof include a methoxy group, an ethoxy group, a propoxy group, and an isopropyl group. Propoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy, tetradecyloxy, pentadecyloxy, hexa Decyloxy group, heptadecyloxy group,
Examples include an octadecyloxy group, a nonadecyloxy group, an eicosyloxy group, a 2-ethylhexyloxy group, and a 3,5-dimethylhexyloxy group. Examples of the halogen atom which may be substituted include chlorine, bromine, fluorine and iodine.

Examples of the optionally substituted hydrocarbonoxy group represented by R ² include a hydroxyl group, an alkoxyl group and an alkoxyl group or an alkenyloxy group optionally substituted by a halogen atom. Here, examples of the alkoxyl group which may be substituted with a hydroxyl group or the like include the same ones as described above and those substituted with these hydroxyl groups. Examples of the alkenyloxy group which may be substituted with a hydroxyl group or the like include, for example, a linear or branched alkenyloxy group having 2 to 36 carbon atoms, specifically, a propenyloxy group, an oleyloxy group, a linoloxy group. And those substituted with a hydroxyl group or the like. Examples of the optionally substituted halogen atom include the same as those described above. R ² may be an oxygen atom or a chlorine atom.

The above R¹May have a substituent
Alkyl group, alkenyl optionally having substituent (s)
Group, phenyl group which may have a substituent,
Preferably, a naphthyl group which may be substituted,
Examples of the alkyl group which may have a group include, for example, methyl
And a trifluoromethyl group are more preferable, and a substituent
As a phenyl or naphthyl group which may have
Is phenyl, chlorophenyl, methylphenyl
Group, ethylphenyl group, propylphenyl group, butylphenyl group
Phenyl, dodecylphenyl, methoxyphenyl,
Ethoxyphenyl group, propoxyphenyl group, butoxy
Phenyl group, hydroxyphenyl group, hydroxynaphthy
And a hydroxyphenyl group is more preferred.
Good. The R ^TwoOf which, an alkoxyl group, an alkenyl
Aryloxy optionally having an oxy group and a substituent
Group is preferred, and an aryloxy optionally having a substituent
Si groups are particularly preferred. In addition, as the alkoxyl group,
Sopropoxy groups are particularly preferred.

Examples of the aromatic hydrocarbonoxy group which may have a substituent represented by R ³ include an alkyl group, a hydroxyl group, an alkoxyl group and an aryloxy group which may be substituted by a halogen atom. . Specifically, a phenoxy group, a hydroxyphenoxy group, a chlorophenoxy group, a dichlorophenoxy group, a trichlorophenoxy group, and a naphthyloxy group are particularly preferable.

Specific examples of the aluminum compound (1) include the following compounds.

[0021]

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When these aluminum compounds are used as an acid catalyst, the amount used is 0.001 to 0.1 per mol of sugar.
Mole, especially 0.001 to 0.01 mole.

The aluminum alkoxide of the catalyst (A) used in the present invention may be any of a mono-, di- and trialkoxide compound, but a trialkoxide compound is more preferable, and the alkoxyl group has 1 to 1 carbon atoms. 4
Is preferred. More specifically, aluminum trimethoxide as aluminum trialkoxide,
Examples thereof include aluminum triethoxide, aluminum triisopropoxide, and aluminum tributoxide, with aluminum triisopropoxide being particularly preferred. These may be commercially available products, or may be a mixture of mono-, di-, and trialkoxide compounds obtained by reacting aluminum trihalide or trialkylaluminum with an alcohol. In this case as well, it is preferable to select conditions that increase the content of the trialkoxide compound.

As the phenol of the catalyst (B) used in the present invention, any phenol having a phenolic hydroxyl group which may be substituted with a halogen atom may be used. For example, phenol, chlorophenol, dichlorophenol, 2,4,4
6-trichlorophenol, 1-naphthol, 2-naphthol, hydroquinone, 2,2-bis (4-hydroxyphenyl) propane, bis (4-hydroxyphenyl)
Sulfone, binaphthol and the like.

The sulfonic acids represented by the general formula (2) of the catalyst (B) used in the present invention include, for example, an alkyl group or an alkenyl in which R ¹ may be substituted by a hydroxyl group, an alkoxyl group or a halogen atom. Group: an alkyl group, a hydroxyl group, an alkoxyl group or an aryl group optionally substituted by a halogen atom. These alkyl groups and the like are the same as those described above.
More specifically, methanesulfonic acid, trichloromethanesulfonic acid, benzenesulfonic acid or naphthalenesulfonic acid which may be substituted with an alkyl group or a hydroxyl group having 1 to 12 carbon atoms, and naphthalenesulfonic acid are preferred. 4,6-trichlorophenol, methanesulfonic acid, p-toluenesulfonic acid, phenolsulfonic acid,
Dodecylbenzenesulfonic acid and naphthalenesulfonic acid are mentioned, and phenolsulfonic acid is particularly preferred.

The amount of the catalyst (A) used is preferably from 0.001 to 0.1 mol, particularly preferably from 0.001 to 0.01 mol, per mol of the saccharide. 1.0
It is preferably used in an amount of from 2.0 to 3.0 times, particularly preferably from 2.0 to 3.0 times by mole.

In the present invention, the sugar used as a raw material may be water-containing or anhydrous, but it is preferable to use anhydrous solid sugar. The mixing ratio of the sugar to the higher alcohol is preferably 1 to 10 times, more preferably 2 to 4 times the mole of the higher alcohol per mole of the sugar.

The manufacturing method of the first invention is, for example, as follows. First, a higher alcohol and a sugar are mixed and heated under reduced pressure with appropriate stirring. Further, a dehydration operation is performed if necessary. Next, an aluminum compound represented by the general formula (1) is added thereto and reacted. After completion of the reaction, the mixture is dispersed in a solvent to remove unreacted sugar, and further neutralized and distilled off the solvent to obtain an alkyl glycoside.

In the second invention, for example, first, a higher alcohol, a catalyst (A), and a catalyst (B) are mixed and heated while appropriately stirring to obtain an alcohol solution of the catalyst.
Using such a solution, a sugar and an alcohol that have been subjected to a dehydration operation are reacted as required. After completion of the reaction, the same treatment as in the first invention can be performed to obtain an alkyl glycoside.

In both the first invention and the second invention, the heating temperature is preferably from 90 to 130 ° C., particularly preferably from 90 to 120 ° C.
The pressure is preferably 5 to 100 mmHg, particularly preferably 20 to 60 mmHg.

The alkyl glycoside obtained in the present invention is preferably an alkyl glycoside having 8 to 14 carbon atoms of an alkyl group which may be linear or branched, having a condensation degree of sugar skeleton of 1 to 1.4. Such alkyl glycosides are prepared from an alcohol having 8 to 14 carbon atoms which may be linear or branched and glucose which may be water-containing or anhydrous.

[0032]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 50 ml of toluene, 3.60 g (17.6 mmol) of aluminum triisopropoxide and 9.21 g (5.28 mmol) of p-phenolsulfonic acid were put into a 100 ml four-necked flask, and a Dean-Stark trap was used. The mixture was refluxed for 3 hours while stirring under nitrogen. The solvent was distilled off and 9.6 was collected.
g of the catalyst was obtained as a pale yellow-white solid. Than solid FT-IR, observed [nu _OH phenolic hydroxyl groups 3281cm ^-1, also observed the disappearance of the starting aluminum triisopropoxide origin [nu _C-H in 2800 to 3000 cm ^-1,
Compounds were identified.

539.0 g of decyl alcohol (3.41)
mol), 245 g (1.36 mol) of anhydrous glucose in 2 L
Put in a four-necked flask and introduce nitrogen, pressure 35-40mm
The temperature was raised to 100 ° C. with stirring and kept at Hg. Next, 2.0 g of the previously prepared catalyst was added, and the mixture was stirred for 9 hours. As a result, the conversion of glucose was 97%. After completion of the reaction, after dispersing in 2 L of hexane, a trace amount of unreacted glucose was removed by filtration, and the mixture was diluted with 2N aqueous sodium hydroxide.
Neutralized to pH 6.7. Hexane and decyl alcohol were distilled off to obtain 371 g of decyl glycoside. The residual amount of decyl alcohol is 1.2% by gas chromatography, and from 200 MHz ¹ H-NMR (CDCl ₃ / D ₂ O solvent), the glucose skeleton in 1 mol of the produced decyl glycoside is 1.28 mol of glucose on average. (Degree of condensation 1.
28)

Example 2 50.20 g (0.318 mol) of decyl alcohol, 15.68 g (0.08 g) of aluminum triisopropoxide
77 mol), 40.12 g of p-phenolsulfonic acid
(0.231 mol) was placed in a 200 ml eggplant-shaped flask, and heated to 100 ° C. while stirring. Further under reduced pressure (50
After stirring at 3 mmHg for 3 hours, the mixture was diluted with 111 g of decyl alcohol to prepare 210 g of a 20% catalyst solution.

539.0 g of decyl alcohol (3.41)
mol), 245 g (1.36 mol) of anhydrous glucose in 2 L
Put in a four-necked flask and introduce nitrogen, pressure 35-40mm
The temperature was raised to 100 ° C. with stirring and kept at Hg. Next, 10 g of the previously prepared 20% catalyst solution was added dropwise, and
After stirring for an hour, the conversion of glucose reached 98%. After completion of the reaction, the mixture was dispersed in 2 L of hexane, and a trace amount of unreacted glucose was removed by filtration, followed by neutralization to pH 6.5 with a 2N aqueous sodium hydroxide solution. Hexane and decyl alcohol were distilled off to obtain 370 g of decyl glycoside. The remaining amount of decyl alcohol is 1.3 according to gas chromatography.
%, And 200 MHz ¹ H-NMR (CDCl ₃ / D ₂
O solvent), the glucose skeleton in 1 mol of the resulting decyl glycoside had an average of 1.30 mol of glucose condensed (condensation degree 1.30).

Comparative Example 1 539.0 g (3.41 mol) of decyl alcohol and 245 g (1.36 mol) of anhydrous glucose were put into a 2 L four-necked flask, and the pressure was maintained at 35 to 40 mmHg under nitrogen introduction.
The temperature was raised to 100 ° C. while stirring. 1.0 g of p-toluenesulfonic acid was added, and the mixture was stirred for 6 hours. As a result, the conversion of glucose was 98%. After the reaction,
After dispersing in 2 L of hexane, a trace amount of unreacted glucose was removed by filtration, and the mixture was neutralized to pH 6.5 with a 2N aqueous sodium hydroxide solution. Hexane and decyl alcohol are distilled off and 27
0 g of decyl glycoside was obtained. The residual amount of decyl alcohol is 1.3% by gas chromatography and 200M
From _{^{Hz 1 H-NMR (CDCl 3}} / D 2 O solvent), glucose skeleton in the product decyl glycoside 1 mol glucose was average 2.40 moles condensation (condensation degree 2.40).

Example 3 50.20 g (0.318 mol) of dodecyl alcohol,
15.68 g of aluminum triisopropoxide (0.
077 mol), 40.12 g of p-phenolsulfonic acid
(0.231 mol) was placed in a 200 ml eggplant-shaped flask, and heated to 100 ° C. while stirring. Further under reduced pressure (50
The mixture was stirred for 3 hours at a pressure of 1.0 mmHg and diluted with 111 g of dodecyl alcohol to prepare 210 g of a 20% catalyst solution.

495.0 g of dodecyl alcohol (2.7
2 mol) and 245 g (1.36 mol) of anhydrous glucose
Put in an L four-necked flask and introduce nitrogen under a pressure of 35-40.
The temperature was raised to 100 ° C. with stirring while maintaining the pressure at mmHg. When 10 g of the previously prepared 20% catalyst solution was added dropwise and stirred for 9 hours, the glucose conversion reached 95%.
After completion of the reaction, the mixture was dispersed in 2 L of hexane, and a trace amount of unreacted glucose was removed by filtration, followed by neutralization to pH 6.5 with a 2N aqueous sodium hydroxide solution. Hexane and dodecyl alcohol were distilled off to obtain 385 g of dodecyl glycoside. The remaining amount of dodecyl alcohol is 1.5 from the gas chromatograph.
%, And 200 MHz ¹ H-NMR (CDCl ₃ / D ₂
O solvent), the glucose skeleton in 1 mol of the resulting decyl glycoside had an average of 1.28 mol of glucose condensed (condensation degree 1.28).

From the above, it was confirmed that in Examples 1 to 3, the saccharide condensation was suppressed and the alkyl glycoside yield was improved as compared with Comparative Example 1.

[0041]

According to the present invention, since sugar condensation is suppressed, the average number of moles of sugar in the sugar skeleton in one mole of the formed alkyl glycoside (the degree of sugar condensation in the formed alkyl glycoside) can be suppressed. Thus, the excess alcohol ratio can be greatly reduced. This effect is particularly remarkable when the sugar is a monosaccharide.

Claims (10)

[Claims] 1. A method for producing an alkyl glycoside from a higher alcohol and a saccharide, comprising the following general formula (1): (Wherein, R ¹ represents a hydrocarbon group which may have a substituent, and R ² has an oxygen atom, a chlorine atom, a hydrocarbon group which may have a substituent or a substituent. R ³ represents an aromatic hydrocarbon oxy group which may have a substituent, and l, m, and n represent at least one of l and n is not 0, and l + m + n = Wherein the aluminum compound represented by the formula (1) is used as an acid catalyst. 2. In the general formula (1), R ¹ is an alkyl group or an alkenyl group which may be substituted with a hydroxyl group, an alkoxyl group or a halogen atom, or an alkyl group, a hydroxyl group, an alkoxyl group or a halogen atom. An aryl group which may be substituted, wherein R ² is a hydroxyl group, an alkoxyl group or an alkyl group, an alkenyl group, an alkoxyl group or an alkenyloxy group which may be substituted by a halogen atom, or an alkyl group, a hydroxyl group, an alkoxyl group; A group or an aryl group which may be substituted with a halogen atom, wherein R ³ is an alkyl group, a hydroxyl group, an alkoxyl group or an aryloxy group which may be substituted with a halogen atom. Production method. 3. The method for producing an alkyl glycoside according to claim ^1, wherein R ¹ in the general formula (1) is a hydroxyphenyl group. 4. A method for producing an alkyl glycoside from a higher alcohol and a saccharide, wherein (A) an aluminum alkoxide and (B) a phenol or a phenol represented by the following general formula (2): (Wherein, R ¹ has the same meaning as described above). 5. The method for producing an alkyl glycoside according to claim 4, wherein the catalyst (A) is an aluminum trialkoxide. 6. The method for producing an alkyl glycoside according to claim 4, wherein the catalyst (A) is aluminum triisopropoxide. 7. The method for producing an alkyl glycoside according to claim 4, wherein the catalyst (B) is a phenol or a naphthol which may be substituted with a halogen atom. 8. The catalyst (B) is a compound represented by the general formula (2)
¹ is a sulfone represented by an alkyl group optionally substituted by a hydroxyl group, an alkoxyl group or a halogen atom, or an alkenyl group, or an aryl group optionally substituted by an alkyl group, a hydroxyl group, an alkoxyl group or a halogen atom The method for producing an alkyl glycoside according to any one of claims 4 to 6, which is an acid. 9. The method for producing an alkyl glycoside according to claim 4, wherein the catalyst (B) is hydroxyphenylsulfonic acid. 10. The method for producing an alkyl glycoside according to claim 1, wherein the saccharide is a monosaccharide.