JPH09227497A - Method for producing N-alkylamide alkanol sulfate ester salt - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a method for producing an N-alkylamidoalkanol sulfate ester salt which has industrially high production efficiency, good hue and odor, and has high industrial utility value. SOLUTION: An N-alkylamide alkanol is sulfated with a sulfating agent and then neutralized to obtain an aqueous solution of N-alkylamide alkanol sulfate ester salt or a water-alcohol mixed solution, which is treated with an oxidizing agent and an inorganic reducing agent. Treatment with at least one member selected from the group consisting of N-alkylamidoalkanol sulfate ester salt (II). Embedded image [R ¹ is a C _6-22 alkyl group, etc., R ² is H, a C _1-22 alkyl group, etc., R ³ is a C _1-5 alkylene group, R ⁴ is a C _2-3 alkylene group, n Represents a number from 0 to 50, and M represents a cation. ]

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an N-alkylamidoalkanol sulfate ester salt, and more specifically, it is an industrially highly efficient N-alkyl having a good production efficiency and a good hue and odor. The present invention relates to a method for producing an amidoalkanol sulfate ester salt.

[0002]

2. Description of the Related Art In recent years,
N-alkyl amide alkanol sulfate ester salt is a surfactant that has excellent foaming power and detergency and is highly safe for the human body and the environment as a cleaning agent for hair, body, dishwashing, etc. (JP-A-7-267)
No. 917). This N-alkylamidoalkanol sulfate ester salt can be obtained by sulfating an N-alkylamidoalkanol and then neutralizing it. However, the N-alkylamide alkanol sulfate ester salt obtained by this method is not sufficiently satisfactory in hue and odor, and requires a purification step such as recrystallization, but such a purification step requires a facility load. However, it is not an industrially advantageous method.

Therefore, an object of the present invention is to provide a method for producing an N-alkylamide alkanol sulfate ester salt which is industrially efficient in production and has a good hue and odor.

[0004]

Means for Solving the Problems As a result of intensive investigations by the present inventors, N-alkylamidoalkanol was sulphated,
Then, the above problem can be solved by treating the N-alkylamide alkanol sulfuric acid ester salt aqueous solution or the water-alcohol mixed solution obtained by neutralization with at least one selected from the group consisting of an oxidizing agent and an inorganic reducing agent. Heading, completed the present invention.

That is, the present invention provides a process for producing an N-alkylamidoalkanol sulfate ester salt, which is characterized by sequentially performing the following steps (A), (B) and (C). Step (A): General formula (I)

[0006]

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[Wherein R ¹ represents a linear or branched alkyl group having 6 to 22 carbon atoms, an alkenyl group or a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ^{2 represents a} hydrogen atom, a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group or a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ³ : represents a linear or branched alkylene group having 1 to 5 carbon atoms. R ^4: represents a linear or branched alkylene group having 2 to 3 carbon atoms, n number of R ⁴ may be the same or different. n: 0 indicating the average number of moles of alkylene oxide added
Any number of 50. ] The process which obtains N-alkyl amide alkanol sulfuric acid ester by sulfating N-alkyl amide alkanol represented by these with a sulfating agent.

Step (B): The N-alkylamidoalkanol sulfate obtained in the step (A) is neutralized to give a compound of the general formula (II)

[0009]

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[Wherein R ¹ , R ² , R ³ , R ⁴ and n are as defined above. M: indicates a cation. ] The process of setting it as the aqueous solution or water-alcohol mixed solution of the N-alkyl amide alkanol sulfuric acid ester salt represented by these.

Step (C): An aqueous solution or water of the N-alkylamidoalkanol sulfate ester salt obtained in Step (B)
A step of treating the alcohol mixed solution with at least one selected from the group consisting of an oxidizing agent and an inorganic reducing agent.

[0012]

Embodiments of the present invention will be described below in detail.

Step (A): This step is a step of sulfating an N-alkylamide alkanol represented by the general formula (I) with a sulfating agent to obtain an N-alkylamide alkanol sulfate.

In the general formula (I), R ¹ has 6 to 22 carbon atoms.
Of a straight-chain or branched-chain alkyl group, alkenyl group, hydroxyalkyl group, or alkyl group having 8 to 12 carbon atoms
The specific examples thereof include hexyl group, octyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, isostearyl group, eicosyl group, docosyl group, oleyl group, 2-ethylhexyl group. Group, 12-hydroxydodecyl group, nonylphenyl group, etc., and a straight-chain or branched-chain alkyl group having 6 to 22 carbon atoms is preferable from the viewpoint of foaming property, and particularly having 8 carbon atoms.
It is preferably a linear alkyl group having 18 to 18 carbon atoms, and more preferably a linear alkyl group having 10 to 14 carbon atoms.

R ² represents a hydrogen atom, a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group or a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. Specific examples thereof include a hydrogen atom, a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, and a hydroxyethyl group, as well as the functional groups exemplified for R ¹ above. It is preferable from the standpoint of sex and chemical stability.

R ³ represents a linear or branched alkylene group having 1 to 5 carbon atoms, specifically, methylene group, ethylene group, propylene group, butylene group, pentylene group, --CH ₂ C.
H (CH ₃ ) CH ₂ CH ₂ — includes a branched 2-methylbutylene group and the like, and a methylene group, —CH ₂ CH (CH ₃ ) CH _{2 in} terms of foamability and chemical stability. A branched 2-methylbutylene group represented by CH ₂ — is preferable, and a methylene group is particularly preferable.

R ⁴ represents a linear or branched alkylene group having 2 to 3 carbon atoms, and specific examples thereof include an ethylene group and a propylene group, preferably an ethylene group. n is an arbitrary number of 0 to 50 which represents the average number of moles of alkylene oxide added, but from the viewpoint of foaming property, safety and chemical stability, an arbitrary number of 0 to 10 is preferable, and n = 0 is Particularly preferred. The n R ^{4 s} may be the same or different.

Preferred specific examples of the N-alkylamidoalkanol represented by the general formula (I) include the following compounds.

[0019]

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[0020]

[Chemical 6]

The N-alkylamidoalkanol represented by the general formula (I) has the general formula (IV)

[0022]

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In the aliphatic amine represented by the formula (wherein R ¹ and R ² have the same meanings as described above), the general formula (V)

[0024]

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(Wherein R ³ has the same meaning as described above), or a cyclic lactone represented by the general formula (VI) HO-R ³ CO ₂ R ⁵ (VI) (wherein R ³ is as described above). R ⁵ represents a hydrogen atom or a straight-chain or branched-chain alkyl group having 1 to 4 carbon atoms, and ω-hydroxycarboxylic acid represented by the formula (5) or its ester is reacted, and if necessary, alkylene oxide. It is obtained by adding.

Specific examples of the aliphatic amine represented by the general formula (IV) (hereinafter abbreviated as aliphatic amine (IV)) include octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine. , Octylmethylamine, decylmethylamine, dodecylmethylamine, tetradecylmethylamine, hexadecylmethylamine, octadecylmethylamine and the like, and octylamine, decylamine, dodecylamine and tetradecylamine are particularly preferable.

Specific examples of the cyclic lactone represented by the general formula (V) (hereinafter abbreviated as cyclic lactone (V)) include β-
Propiolactone, γ-butyrolactone, δ-valerolactone, 2-methyl-δ-valerolactone, ε-caprolactone, 2-methyl-γ-butyrolactone, and the like, and 2-methyl-δ-valerolactone, ε-caprolactone. Is particularly preferred.

Specific examples of the ω-hydroxycarboxylic acid represented by the general formula (VI) or its ester (hereinafter abbreviated as ω-hydroxycarboxylic acid or its ester (VI)) include:
Lactic acid, glycolic acid, 2-hydroxypropionic acid, 3
-Hydroxybutyric acid, 4-hydroxypentanoic acid, 4-hydroxy-3-methylpentanoic acid, 5-hydroxyhexanoic acid, or their methyl, ethyl, propyl, butyl ester, etc., such as methyl glycolate, ethyl glycolate, Propyl glycolate, butyl glycolate, methyl 2-hydroxypropionate, methyl 3-hydroxybutyrate, methyl 4-hydroxypentanoate,
Methyl 5-hydroxyhexanoate is preferred, especially methyl glycolate, ethyl glycolate and 5-hydroxyhexanoate for reasons of foamability and chemical stability.

Aliphatic amine (IV) and cyclic lactone (V)
The reaction with 1 to 1.5 times the molar amount of the cyclic lactone (V) and the aliphatic amine (IV) in the absence of solvent or, if necessary, in a solvent such as toluene, xylene, dioxane, DMF, 0 to 1
80 ° C, preferably 70-150 ° C, particularly preferably 80-130
It is carried out at a suitable temperature of ° C for 1 to 100 hours, preferably 1 to 20 hours.

The reaction between the aliphatic amine (IV) and the ω-hydroxycarboxylic acid or its ester (VI) is carried out by mixing the aliphatic amine (IV) with 1 to 2.0 moles of the ω-hydroxycarboxylic acid or its ester. (VI) without solvent, if necessary, in the presence of a base catalyst such as CH ₃ ONa, KOH, NaOH, 40 to 200
C., preferably 60 to 150.degree. C., for 1 to 100 hours, preferably 1 to 20 hours under reduced pressure for dehydration or dealcoholization.

The alkylene oxide addition reaction is carried out in the presence of an alkali or acid catalyst at a temperature of 120 to 180 ° C. for 1 to 10 hours. Examples of the alkylene oxide include ethylene oxide and propylene oxide, and ethylene oxide is preferable.

Examples of alkali catalysts include alkali metal hydroxides, alkali metal carbonates, organic amines, metal oxides, alkoxylates, and the like, and acid catalysts include
Examples include Lewis acids such as boron trifluoride (BF ₃ ), tin tetrachloride (SnCl ₄ ), antimony pentachloride (SbCl ₅ ), magnesium oxide (MgO), aluminum oxide (Al ₂ O ₃ ), and metal oxides. To be

In this step, the N-alkylamidoalkanol represented by the general formula (I) obtained as described above is reacted with a sulfating agent for sulfation. Examples of the sulfating agent include chlorosulfonic acid, sulfuric acid anhydride, fuming sulfuric acid, concentrated sulfuric acid, sulfamic acid, etc., but from the viewpoint of reaction yield, chlorosulfonic acid, sulfuric acid anhydride, sulfamic acid are preferable, and chlorosulfonic acid is particularly preferable. preferable.

The sulfation reaction is carried out by N represented by the general formula (I).
-Using 1 to 1.5 times the molar amount of a sulfating agent with respect to the alkylamidoalkanol, using 0 to 10 times the amount of hexane, dichloromethane, chloroform, 1,2-dichloroethane, dimethylformamide, dimethylsulfoxide, dioxane, etc. It is carried out at -80 ° C, preferably -30 to 50 ° C for 1 to 20 hours.

Step (B): In this step, the N-alkylamide alkanol sulfate ester obtained in the step (A) is neutralized to give the N-alkylamide alkanol sulfate ester represented by the above general formula (II). This is a step of preparing an aqueous salt solution or a water-alcohol mixed solution.

In this step, N obtained in step (A)
-Alkyl amide alkanol sulfate and 0.9-
Neutralize 1.5 times equivalent amount of basic substance in a solvent such as water, ethanol or methanol at -50 to 80 ° C for 0.1 to 1 hour. Examples of the basic substance used here include alkali metal or alkaline earth metal hydroxides, carbonates or bicarbonates, ammonia, alkanolamines having 2 to 9 carbon atoms, and alkylamines having 1 to 22 carbon atoms. Or alkenylamine, alkyl or alkenyl-substituted pyridine having 1 to 18 carbon atoms, or basic amino acid,
Specifically, inorganic alkali such as sodium hydroxide, potassium hydroxide, lithium hydroxide, barium hydroxide, sodium hydrogen carbonate, sodium carbonate, potassium carbonate, or ammonia, monoethanolamine, diethanolamine, triethanolamine, methylamine , Dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, basic amino acids and the like,
Ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, monoethanolamine, diethanolamine and triethanolamine are preferable, and sodium hydroxide and sodium carbonate are particularly preferable. These are subjected to neutralization of the sulfate as an aqueous solution or an alcohol solution. The degree of neutralization can be set arbitrarily.

The concentration of the aqueous solution of N-alkylamide alkanol sulfate ester salt or water-alcohol mixed solution obtained in this step is not particularly limited, but is preferably 10 to 50% by weight, more preferably 20 to 40% by weight.

Step (C): In this step, the aqueous solution or water-alcohol mixed solution of the N-alkylamide alkanol sulfate ester salt obtained in Step (B) is selected from the group consisting of an oxidizing agent and an inorganic reducing agent. This is a step of treating with at least one kind.

Examples of the oxidant used in this step include alkali metal hypochlorite, hydrogen peroxide and the like, preferably sodium hypochlorite and hydrogen peroxide, and particularly preferably hypochlorous acid. Sodium acid. Those commercially available as an aqueous solution can be used as they are.

Further, the inorganic reducing agent used in this step is represented by the general formula (III) E (BH ₄ ) _x (III) (wherein E is an alkali metal, Ca, Zn or (CH ₃ ) ₄ N Yes, when E is an alkali metal or (CH ₃ ) ₄ N, x is 1, E is
When Ca or Zn, x is 2. ) And a borohydride salt represented by. Specific examples of the borohydride salt include lithium borohydride, sodium borohydride,
Examples thereof include potassium borohydride, tetramethylammonium borohydride, calcium borohydride, zinc borohydride, and the like, alkali metal borohydride salts are preferable, and sodium borohydride is particularly preferable. As these borohydride salts, those which are commercially available as a powder or an alkaline aqueous solution can be used as they are.

In this step, the amount of at least one selected from the group consisting of an oxidizing agent and an inorganic reducing agent is 0.005 to 10 relative to the N-alkylamide alkanol sulfate ester salt represented by the general formula (II). % By weight is preferred,
01 to 1% by weight is particularly preferred. A good effect is obtained when the amount added is 0.005% by weight or more.
% By weight or less is preferred.

In this step, the N obtained in the step (B) is
-At least one selected from the group consisting of an oxidizing agent and an inorganic reducing agent may be added to an aqueous solution of an alkylamide alkanol sulfate ester salt or a water-alcohol mixed solution, and the treatment may be performed. Then, it is particularly preferable to add an inorganic reducing agent. The amount of the oxidizing agent used at this time is 0.005 to the N-alkylamide alkanol sulfate ester salt represented by the general formula (II).
5% by weight is preferable, and 0.01 to 1% by weight is particularly preferable.
The amount of inorganic reducing agent is 0.5 with respect to the added oxidizing agent.
It is preferably -10 to 10 times, particularly preferably 1 to 5 times.
Further, 0.005 to 5% by weight is preferable, and 0.01 to 0.5% by weight is particularly preferable, with respect to the N-alkylamide alkanol sulfate ester salt represented by the general formula (II).

The treatment temperature of at least one selected from the group consisting of an oxidizing agent and an inorganic reducing agent in this step is not particularly limited, but usually 15 to 80 ° C. is preferable. Also the pH at that time
Although there is no particular limitation, the pH is usually 4 to 13, preferably 6 to 12. The treatment time is preferably 0.1 to 10 hours, more preferably 0.5 to 2 hours.

In the present invention, if necessary, the inorganic reducing agent such as excess borohydride remaining next in the system can be decomposed with an acid such as sulfuric acid or paratoluenesulfonic acid. After completion of the decomposition, the pH can be adjusted by adding a suitable base such as sodium hydroxide.

In the present invention, by the treatment with at least one selected from the group consisting of such an oxidizing agent and an inorganic reducing agent, a high-quality general formula (II) with improved hue and odor can be obtained. It has become possible to produce the N-alkylamide alkanol sulfate ester salt. The aqueous solution obtained in the present invention may be used as it is as a surfactant such as a detergent, or may be dried to obtain a powder product.

[0046]

According to the production method of the present invention, an N-alkylamide alkanol sulfate ester salt having a good hue and odor can be industrially produced at low cost.

[0047]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.
The percentages in the examples are on a weight basis unless otherwise specified.

Example 1 250.2 g (1.03 mol) of N-lauryl glycolic acid amide and 2.5 kg of hexane were placed in a 5-necked four-necked flask equipped with a stirrer, a condenser, a thermometer and a dropping funnel and heated to 65 ° C.
After heating to dissolve once, cool down to 40 ℃,
-Lauryl glycolic acid amide was precipitated to give a uniform suspension solution. There, 119.8g (1.03mo) of chlorosulfonic acid
l) was added dropwise over about 1 hour. Meanwhile, the temperature in the system is 4
It rose from 0 ℃ to 42 ℃. After completion of dropping, the mixture was heated while bubbling with nitrogen, kept at a temperature of 60 ° C., and stirred for about 3 hours to obtain a reaction product represented by the following formula (VI). The reaction rate is
It was 99% (the reaction was traced by HPLC and calculated from the peak area ratio of the raw material and the reaction product. The reaction rate was determined by the same method below).

[0049]

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Next, the reaction mixture was cooled to 20 ° C. or lower and neutralized by adding 77.1 g of 48% sodium hydroxide aqueous solution, 54.5 g of 20% sodium carbonate aqueous solution, 568 g of ethanol, and 750 g of ion-exchanged water. After neutralization, the stirring was stopped and the mixture was allowed to stand for a while, and separated into layers (upper layer: hexane layer, lower phase: ethanol-
Then, 1830 g (pH 8.5) of an ethanol-water solution containing about 20% of a compound represented by the following formula (VII) was obtained.

[0051]

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600 g of this ethanol-water solution was placed in a 4-necked flask having a capacity of 1 liter, equipped with a stirrer, a condenser and a thermometer, and 0.59 g of a 10% sodium hypochlorite solution in water.
(500 ppm of sodium hypochlorite was added to the compound represented by the above formula (VII)), and the mixture was heated to 50 ° C. and stirred for 1 hour. Subsequently, 0.09 g of sodium borohydride (3 mol times with respect to sodium hypochlorite) was added, and the mixture was added at 50 ° C. to 1
After stirring for an hour, the solvent was distilled off under reduced pressure to give the above formula (VI
A 30% aqueous solution of the compound represented by I) was obtained. The resulting solution was APHA 150 in hue. Further, the odor was evaluated by 10 panelists according to the following criteria, and the result was ◎ to ○.

<Odor Evaluation Criteria> ◎: No odor, excellent ◎ to ○: Slight odor, good ◯: Smell, but usable level △: Strong odor, unusable ×: Very strong odor Unbearable Example 2 About 20% of the compound represented by the formula (VII) obtained in Example 1 was used.
Take 600 g of ethanol-water solution containing it in a 4-liter flask with a capacity of 1 liter equipped with a stirrer, a cooling tube, and a thermometer.
0.58 g of sodium hypochlorite aqueous solution (500 ppm of sodium hypochlorite with respect to the compound represented by the above formula (VII))
Was added and the mixture was heated to 50 ° C. and stirred for 1 hour, then the solvent was distilled off under reduced pressure to obtain a 30% aqueous solution of the compound represented by the above formula (VII). The resulting solution was APHA 200 in hue. The odor was evaluated in the same manner as in Example 1.
Met.

Example 3 About 20% of the compound represented by the formula (VII) obtained in Example 1
600 g of ethanol-water solution containing it was placed in a 4-liter flask with a capacity of 1 liter equipped with a stirrer, a condenser and a thermometer, and 0.046 g of sodium borohydride (sodium borohydride for the compound represented by the above formula (VII)) Of 400 ppm) was added and the mixture was heated to 50 ° C. and stirred for 1 hour, and then the solvent was distilled off under reduced pressure to obtain a 30% aqueous solution of the compound represented by the above formula (VII). The resulting solution had a hue of APHA 200-250. The odor was evaluated in the same manner as in Example 1.
Met.

Comparative Example 1 About 20% of the compound represented by the formula (VII) obtained in Example 1 was used.
600 g of ethanol-water solution containing it was taken in a 4-liter flask with a capacity of 1 liter equipped with a stirrer, a cooling tube, and a thermometer, and the solvent was distilled off under reduced pressure without any treatment, and the above formula (VI
A 30% aqueous solution of the compound represented by I) was obtained. The resulting solution had a hue of APHA 250-300. When the odor was evaluated in the same manner as in Example 1, the result was Δ.

Example 4 Using 236.9 g (1.1 mol) of N-decyl glycolic acid amide, 2.4 kg of hexane and 128.2 g (1.1 mol) of chlorosulfonic acid,
In the same manner as in Example 1, 1840 g (pH 9.0) of an ethanol-water solution containing about 20% of the compound represented by the following formula (VIII) was obtained.

[0057]

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600 g of this ethanol-water solution was placed in a 4-necked flask having a capacity of 1 liter equipped with a stirrer, a condenser and a thermometer, and the solvent was distilled off under reduced pressure to give the compound represented by the above formula (VIII). To obtain a 30% aqueous solution. Add 3.5 g of 10% sodium hypochlorite aqueous solution (0.1% sodium hypochlorite to the compound represented by the above formula (VIII)) to this.
Heat to 50 ° C. and stir for 1 hour. Subsequently, 0.53 g of sodium borohydride (3 mol times with respect to sodium hypochlorite) was added and stirred at 50 ° C. for 1 hour to obtain a 30% aqueous solution of the compound represented by the above formula (VIII). . The resulting solution was hue G2. When the odor was evaluated in the same manner as in Example 1, the result was ◯.

Comparative Example 2 About 20% of the compound represented by the formula (VIII) obtained in Example 4 was used.
600 g of ethanol-water solution containing it was placed in a 4-liter flask with a capacity of 1 liter equipped with a stirrer, a cooling tube, and a thermometer, and the solvent was distilled off under reduced pressure without any treatment, and the above formula (VII
A 30% aqueous solution of the compound represented by I) was obtained. The resulting solution was hue G3. When the odor was evaluated in the same manner as in Example 1, it was x.

Example 5 N-laurylamide methoxyethanol 256.0 g (0.9 mo
l), hexane 2.5kg, chlorosulfonic acid 104.9g (0.9mol)
1820 g of ethanol-water solution containing about 20% of the compound represented by the following formula (IX) (pH:
I got 9.4).

[0061]

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600 g of this ethanol-water solution was placed in a 4-necked flask having a capacity of 1 liter, equipped with a stirrer, a condenser and a thermometer, and 0.57 g of a 10% sodium hypochlorite solution was added.
(0.05% of sodium hypochlorite with respect to the compound represented by the above formula (IX)) was added, and the mixture was heated to 50 ° C. and stirred for 1 hour. Then, 0.09 g of sodium borohydride (3 mol times with respect to sodium hypochlorite) was added, and the mixture was stirred at 50 ° C for 1 hour, and then the solvent was distilled off under reduced pressure to obtain the compound represented by the above formula (IX). A 30% aqueous solution of the compound is obtained. The resulting solution has a hue A
It was PHA 150. When the odor was evaluated in the same manner as in Example 1, it was ◎ to ◯.

Example 6 600 g of an ethanol-water solution containing about 20% of the compound represented by the formula (IX) obtained in Example 5 was added to a 1-liter four-necked flask equipped with a stirrer, a condenser and a thermometer. Then, 0.33 g of 35% hydrogen peroxide solution (0.1% of hydrogen peroxide to the compound represented by the above formula (IX)) was added, and the mixture was heated to 50 ° C. and stirred for 1 hour. Subsequently, 0.19 g of sodium borohydride (1.5 mol times of sodium borohydride relative to hydrogen peroxide) was added and heated to 50 ° C., stirred for 1 hour, and then the solvent was distilled off under reduced pressure. A 30% aqueous solution of the compound represented by the formula (IX) was obtained. The resulting solution had a hue of APHA 200-250. The odor was evaluated in the same manner as in Example 1.
Met.

Comparative Example 3 600 g of an ethanol-water solution containing about 20% of the compound represented by the formula (IX) obtained in Example 5 and a 1-liter four-necked flask equipped with a stirrer, a condenser and a thermometer. Then, the solvent was distilled off under reduced pressure without any treatment to obtain a 30% aqueous solution of the compound represented by the formula (IX). The resulting solution was hue G2. When the odor was evaluated in the same manner as in Example 1, the result was Δ.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Fujio 1334 Minato Minato, Wakayama City, Wakayama Prefecture Kao Corporation Laboratory

Claims (6)

[Claims] 1. A method for producing an N-alkylamidoalkanol sulfate ester salt, which comprises sequentially performing the following steps (A), (B) and (C). Step (A): General formula (I) [In the formula, R ¹ represents a linear or branched alkyl group having 6 to 22 carbon atoms, an alkenyl group or a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ^{2 represents a} hydrogen atom, a linear or branched alkyl group having 1 to 22 carbon atoms, an alkenyl group or a hydroxyalkyl group, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R ³ : represents a linear or branched alkylene group having 1 to 5 carbon atoms. R ^4: represents a linear or branched alkylene group having 2 to 3 carbon atoms, n number of R ⁴ may be the same or different. n: 0 indicating the average number of moles of alkylene oxide added
Any number of 50. ] The process which obtains N-alkyl amide alkanol sulfuric acid ester by sulfating N-alkyl amide alkanol represented by these with a sulfating agent. Step (B): The N-alkylamidoalkanol sulfate obtained in the step (A) is neutralized to give a compound represented by the general formula (II): [In the formula, R ¹ , R ² , R ³ , R ⁴ , and n are as defined above. M: indicates a cation. ] The process of setting it as the aqueous solution or water-alcohol mixed solution of the N-alkyl amide alkanol sulfuric acid ester salt represented by these. Step (C): A step of treating the aqueous solution of the N-alkylamidoalkanol sulfate ester salt or the water-alcohol mixed solution obtained in Step (B) with at least one selected from the group consisting of an oxidizing agent and an inorganic reducing agent. 2. The method according to claim 1, wherein the treatment with an oxidizing agent is followed by the treatment with an inorganic reducing agent. 3. The method according to claim 1, wherein the oxidizing agent is at least one selected from the group consisting of sodium hypochlorite and hydrogen peroxide. 4. The inorganic reducing agent is represented by the general formula (III) E (BH ₄ ) _x (III) (wherein E is an alkali metal, Ca, Zn or (CH ₃ ) ₄ N, and E is an alkali metal. Or (CH ₃ ) ₄ N, x is 1, E is
When Ca or Zn, x is 2. ) It is a borohydride salt represented by these, The manufacturing method as described in any one of Claims 1-3. 5. The method according to claim 4, wherein the borohydride salt is an alkali metal borohydride salt. 6. R ² is a linear alkyl group having 8 to 18 carbon atoms, R ²
Is a hydrogen atom, R ³ is a methylene group, and n is 0.
5. The manufacturing method according to any one of 5 above.