JP2002371071A - Method for producing oxathiazines - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method by which oxathiazines are produced industrially advantageously. SOLUTION: This method produces the oxathiazines expressed by formula (2) by subjecting sulfonic acids expressed by formula (1) to the cyclizing dehydration reaction in the presence of a phosphorus compound containing a halogen and having dehydrating property (e.g. phosphorus halogenides, phosphor oxy halogenides, or the like). In the formulae, (R<1> and R<2> are each independently H or an organic group inert to the reaction, R<3> is H or an organic group inert to the reaction, an organic group which combines with a nitrogen atom to form a salt or an inorganic metal atom; X is H or an organic salt or an inorganic salt which forms a salt with a sulfonate group).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing oxathiazines useful for obtaining sweeteners and the like in the food industry.

[0002]

2. Description of the Related Art Oxathiazines, especially compounds having a 3,4-dihydro-1,2,3-oxathiazine ring,
Since it has an acidic hydrogen atom bonded to a nitrogen atom in the molecule, it can form a salt with a base. Among the salts that are formed, some of the non-toxic salts (eg, Na, K, Ca, etc.) have a strong sweetness, and such salts are sweeteners in the food industry. Has been used as

As a method for producing the aforementioned 3,4-dihydro-1,2,3-oxathiazines, for example, Angevante Chemie International Edition, Vol. 12, No. 10, (1973), No. 86
9-876 (or DE-A-245 306)
No. 3), acetoacetamide-N-sulfonic acid halides (fluoride and chloride) are allowed to act on a base (methanolic KOH, etc.) to open the ring to give 3,4-dihydro-1,2,3-oxathiazines. (6-methyl-
3,4-dihydro-1,2,3-oxathiazine-4-
On-2,2-dioxide or a salt thereof). On the other hand, the acetoacetamide-
N-sulfonic acid halides are obtained by reacting halosulfonyl isocyanates with a suitable acetoacetylating agent. However, in such a method, halosulfonyl isocyanate or amide sulfo halide used as a starting material is a special compound and is not easy to handle, so that it is not suitable as an industrial method.

[0004] As another method, Japanese Patent Laid-Open Publication No.
No. 48, Japanese Patent Publication No. 5-70627 and Japanese Patent Publication No. 6-25189 disclose a method of reacting acetoacetamido-N-sulfonic acid or a salt thereof with SO ₃ in an inert organic solvent to carry out a cyclization dehydration reaction. By subjecting it to ring closure,
A method for producing 6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide or a salt thereof is disclosed. However, even in such a method, attention must be paid to the handling of SO _{3 to be} used.
Liquid SO ₂ , methylene chloride and the like are used as inert solvents for SO ₃ . SO ₂ is a liquefied gas and is not easy to handle in terms of odor and toxicity.

[0005] In such a production method, no effective cyclizing dehydrating agent has been found as an alternative to sulfuric anhydride (SO ₃ ), and there is no other means than using the above-mentioned solvent.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for industrially and advantageously producing oxathiazines using a cyclizing dehydrating agent which is relatively easy to handle.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that a method for producing oxathiazines by cyclodehydration of acetoacetamide-N-sulfonic acid or a salt thereof is described. The present inventors have found that a target compound can be obtained by using a specific halogen-containing phosphorus compound as a cyclizing dehydrating agent, and completed the present invention.

That is, in the present invention, the following formula (1)

[0009]

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(Wherein R ¹ and R ² are the same or different and each represent a hydrogen atom or a reaction-inactive organic group, and R ³ is bonded to a hydrogen atom, a reaction-inactive organic group, or a nitrogen atom. Represents an organic group or an inorganic metal atom that forms a salt with X, X represents a hydrogen atom or an organic base or an inorganic base that forms a salt with a sulfonate group), and subjected to a cyclization dehydration reaction; The following equation (2)

[0011]

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(Wherein R ¹ , R ² and R ³ are as defined above)
In a method for producing oxathiazines represented by
The cyclization dehydration reaction is performed in the presence of a halogen-containing phosphorus compound having dehydration properties. The halogen-containing phosphorus compound having dehydration properties may be phosphorus halide, phosphorus oxyhalide, or the like. The halogen-containing phosphorus compound may be used in an amount of about 1 to 20 mol per 1 mol of the sulfonic acids.

The above R¹And R^TwoIs a hydrogen atom, alkyl
Group, alkenyl group, alkynyl group, cycloalkyl group,
It may be an acyl group, an aralkyl group, an aryl group, etc.
K, R ^ThreeRepresents a hydrogen atom, an alkyl group, an alkenyl group,
Quinyl group, cycloalkyl group, acyl group, aralkyl
Group, aryl group, organic compound that forms a salt by combining with a nitrogen atom
It may be a group or an inorganic metal atom. The sulfone
The acids are acetoacetamide-N-sulfonates.
You may. As oxathiazines, 6-methyl-
3,4-dihydro-1,2,3-oxathiazine-4-
On-2,2-dioxide or a salt thereof.
You.

The present invention provides a cyclizing dehydrating agent for cyclizing and dehydrating a sulfonic acid represented by the above formula (1), wherein the cyclizing dehydration agent comprises a halogen-containing phosphorus compound having a dehydrating property. Agents are also included.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the sulfonic acids of the above formula (1) are subjected to a cyclization dehydration reaction in the presence of a halogen-containing phosphorus compound having a dehydrating property to give an oxathiazine (3) of the above formula (2). , 4-dihydrooxathiazines or salts thereof).

In the above formula (1), R ¹ , R ² and R ³
The organic group inert to the reaction represented by is not particularly limited as long as it is inert to the reaction, and may be an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an acyl group, an aralkyl group, and an aryl group. And the like.

The alkyl group includes a straight-chain or branched C
_1-10Alkyl group (for example, methyl group, ethyl group,
Group, butyl group, isobutyl group, tert-butyl group, etc.
C_{1- 6}Alkyl group, etc.). Alkenyl group
Is a linear or branched C_2-10Alkenyl groups (eg, bi
Nil, allyl, isopropenyl, 1-butenyl
Group such as a group or a 2-butenyl group_2-5Alkenyl group)
included. Alkynyl groups include linear or branched C_2-10
Alkynyl group (for example, ethynyl group, propynyl group, 1
-Butynyl group, 2-butynyl group, etc._2-5Alkynyl
Groups). Examples of cycloalkyl groups include
For example, cyclopropyl, cyclobutyl, cyclopent
C, such as_3-10Cycloalkyl group
(Preferably C_4-8Cycloalkyl group). A
The sil group has a linear or branched C_2-10Aliphatic acyl group
(E.g., acetyl, propionyl, butyryl,
Isobutyryl group, valeryl group, etc.) or C_7-11Good
Aromatic acyl groups (e.g., benzoyl, toluyl,
Etc.). Aralkyl groups include:
C _6-10Aryl-C_1-4Alkyl groups (eg, benzyl
And the like, and the aryl group is phenyl
C such as a group_6-10And an aryl group.

In the above formula (1), the organic group forming a salt by bonding to the nitrogen atom represented by R ³ includes an organic group forming an ammonium salt or an amine salt, for example, an alkyl group (for example, C Examples thereof include a _1-10 alkyl group), a cycloalkyl group (eg, a C _3-12 cycloalkyl group), an aryl group (eg, a C _6-10 aryl group), and an aralkyl group (eg, a benzyl group).

In R ³ , examples of the inorganic metal atoms forming a salt include alkali metals (Group 1A metals) such as Na, K and Li, and alkaline earth metals (Group 2A metals) such as Mg, Ca and Sr. Periodic table 3B of metals, Al, Ga, etc.
Group metal, transition metal (eg, group 3A metal of the periodic table, group 4A metal of the periodic table, group 5A metal of the periodic table, group 6A metal of the periodic table, M
Periodic Table 7A metals such as n, Periodic Table 8 metals such as Fe, Periodic Table 1B metals such as Cu, Ag, and Au; Periodic Table 2B metals such as Zn; Periodic Table 4B metals; and Periodic Table 5B
Group metals). Preferred inorganic metal atoms include
Examples thereof include 1-3 valent metals, for example, alkali metals (such as Na and K), alkaline earth metals (such as Mg and Ca), Al, and transition metals (such as Mn and Fe). In consideration of economy, safety, and the like, alkali metals such as Na and K are often used.

The organic base which forms a salt with the sulfonate group represented by X in the above formula (1) includes amines corresponding to amine salts, for example, aliphatic amines [primary amines (eg, methylamine, Ethylamine), second
Tertiary amines (eg, dimethylamine, ethylmethylamine, etc.), tertiary amines (eg, trimethylamine,
Alicyclic amines (eg, cyclopentylamine, cyclohexylamine, etc.), aromatic amines (eg, monoarylamines such as aniline and dimethylaniline, diarylamines such as diphenylamine, and triarylamines such as triphenylamine) And cyclic amines (for example, pyridine, quinoline, piperidine and derivatives thereof). Preferred amines are aliphatic amines, among which tertiary amines are preferred.

In X, the inorganic base which forms a salt with a sulfonate group includes ammonia, alkali metal hydroxides (eg, sodium hydroxide, potassium hydroxide, etc.), alkali metal carbonates (eg, sodium carbonate,
Potassium carbonate, etc.), alkali metal bicarbonates (eg, sodium bicarbonate, potassium bicarbonate, etc.), hydroxides of alkaline earth metals (eg, calcium hydroxide, magnesium hydroxide, etc.), carbonic acid of alkaline earth metals Hydrogen salts (eg, calcium bicarbonate, magnesium bicarbonate, etc.) and the like can be mentioned.

In the above formulas (1) and (2), R ¹ to
R ³ and X can be appropriately combined, and for example, the following combinations are preferred.

R ¹ and R ² : hydrogen atom, C _1-4 alkyl group R ³ : hydrogen atom, C _1-4 alkyl group, alkali metal, alkaline earth metal X: aliphatic amine (particularly tertiary amine) , Ammonium, alkali metals and alkaline earth metals Preferred sulfonic acids of the formula (1) include acylacetamide-N-sulfonates wherein R ¹ is an alkyl group and R ² and R ³ are hydrogen atoms. Among them, acetoacetamide-N-sulfonate wherein R ¹ is a methyl group,
In particular, acetoacetamide-N wherein X is ammonium
-Ammonium sulfonates (particularly tertiary ammonium salts) are preferred.

In the present invention, the halogen-containing phosphorus compound is used as a cyclizing dehydrating agent for the sulfonic acids (1).

Examples of such a halogen-containing phosphorus compound include phosphorus halides [phosphorous fluorides such as phosphorus trifluoride and phosphorus pentafluoride; phosphorus chlorides such as phosphorus dichloride, phosphorus trichloride and phosphorus pentachloride; Phosphorus bromide such as phosphorus dibromide, phosphorus tribromide, phosphorus pentabromide and phosphorus heptabromide; phosphorus iodide such as phosphorus diiodide, phosphorus triiodide and phosphorus pentaiodide; phosphorus chloride fluoride ( PFCl ₂ , PF ₃ Cl _2, etc.), phosphorus bromide (PCl ₃ Br ₂ , PBr ₃ Cl ₂ , PBrCl _4, etc.),
Phosphorous halides having a plurality of different types of halogen atoms such as phosphorus iodide chloride (PCl ₃ I ₂ , PCl ₆ I etc.), phosphorus oxyhalide [phosphoryl fluoride POF
Phosphorous oxyfluoride such as ₃ ; phosphoryl monochloride POC
l, Phosphoryl oxychloride such as phosphoryl trichloride POCl ₃ , pyrophosphoryl chloride P ₂ O ₃ Cl ₄ , metaphosphoryl chloride PO ₂ Cl; phosphorus oxybromide such as phosphoryl bromide POBr ₃ ; phosphorus oxyiodide; phosphoryl fluoride chloride (P
OCl ₂ F, POClF ₂ ), phosphoryl bromide (P
OBrF ₂ , POBr ₂ F), phosphoryl bromide chloride (PO
Phosphorus oxyhalide containing a plurality of different types of halogen atoms, such as BrCl ₂ and POBr ₂ Cl).

These halogen-containing phosphorus compounds can be used alone or in combination of two or more. Of the halogen-containing phosphorus compounds, phosphorus compounds containing at least a chlorine atom are preferable, and phosphorus compounds containing fluorine and / or chlorine (particularly chlorine) (phosphorous halides such as phosphorus fluoride and phosphorus chloride; phosphorus oxyfluoride, oxyfluoride Phosphorous oxyhalides such as phosphorus chloride) are preferred.

The halogen-containing phosphorus compound is generally used in an amount of at least 1 mol (for example, 1 to 20 mol), preferably 1 to 10 mol, particularly 1 to 10 mol per mol of sulfonic acids.
It is used in a ratio of about 5 mol.

The cyclodehydration reaction of the sulfonic acid (1) as a substrate can be carried out in the presence or absence of a solvent. As the reaction solvent, various inorganic or organic solvents inert to the reaction (especially acid anhydride) can be used.
Usually, an organic solvent inert to the reaction is used. As the solvent, a substantially anhydrous solvent is usually used.
When the halogen-containing phosphorus compound is used, the reaction can proceed even in the absence of a solvent.

Examples of the organic solvent include aliphatic hydrocarbons (eg, pentane, hexane, octane), alicyclic hydrocarbons (eg, cyclohexane), and aromatic hydrocarbons (eg, benzene, toluene, xylene, ethylbenzene). ), Halogenated hydrocarbons (e.g., haloalkanes such as dichloromethane, dichloroethane, chloroform, trichloroethylene, tetrachloroethylene, and trichlorofluoroethylene), alcohols (e.g., methanol, ethanol, 1-propanol, 2-
Propanol, 1-butanol, 2-butanol, t-
Aliphatic alcohols such as butanol; alicyclic alcohols such as cyclopentanol and cyclohexanol; aromatic alcohols such as benzyl alcohol); esters (eg, methyl acetate, ethyl acetate, butyl acetate;
Carboxylic acid esters such as methyl propionate); ketones (eg, aliphatic ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; alicyclic ketones such as cyclohexanone); ethers (eg, diethyl ether, diisopropyl ether, Chain ethers such as 2,2-dimethoxyethane, cellosolve, carbitol, diglyme, diethylene glycol dimethyl ether; anisole, 1,2-dimethoxybenzene,
Aromatic ethers such as diphenyl ether; cyclic ethers such as tetrahydrofuran, dioxolan, dioxane, etc.), lower carboxylic acids (eg, formic acid, acetic acid, propionic acid, butyric acid), nitriles (eg, acetonitrile, propionitrile, butyronitrile, benzoyl) Examples thereof include nitriles and the like, amides (formamide, acetamide, dimethylformamide (DMF), dimethylacetamide and the like), sulfoxides (eg, dimethylsulfoxide, sulfolane, 2-methylsulfolane, 3-methylsulfolane and the like). These solvents may be used alone or in combination of two or more.
Particularly preferred solvents include ethers (such as a chain ether such as diethyl ether), nitriles (such as acetonitrile), and nitroalkanes (such as nitromethane and nitroethane).

The ratio of the reaction solvent is not particularly limited, and for example, based on 100 parts by weight of the sulfonic acid (1) as the substrate,
It can be selected from a wide range of about 1 to 2000 parts by weight, preferably 10 to 2000 parts by weight, more preferably 100 parts by weight.
About 2000 parts by weight. The substrate concentration in the reaction mixture is not particularly limited, and is, for example, 0.1 to 50% by weight, preferably 0.5 to 30% by weight, and more preferably 1 to 15% by weight.
% By weight.

The reaction is usually carried out under normal pressure, but may be carried out under reduced pressure or under increased pressure. The reaction is carried out at an appropriate temperature (for example, a temperature higher than the melting point of the reaction system and lower than the boiling point), for example, about -70 ° C to 200 ° C, preferably-
It can be carried out at a temperature of about 40 ° C. to 70 ° C. and at room temperature (1
(About 5 to 30 ° C.). The reaction time is not particularly limited, and is, for example, about 0.1 to 10 hours, preferably about 0.1 to 5 hours, and more preferably about 0.1 to 2 hours.

In the reaction, the order of adding or mixing the raw materials,
The form of addition is not particularly limited. For example, a halogen-containing phosphorus compound may be added to the sulfonic acid (1) as a substrate, and the sulfonic acid (1) may be added to the halogen-containing phosphorus compound.
May be added. Further, the sulfonic acids (1) and the halogen-containing phosphorus compound may be simultaneously introduced into the reaction system.
Each of the sulfonic acids (1) and the halogen-containing phosphorus compound may be used without being diluted with a solvent or the like, or may be used as a solution diluted with a solvent.

The above reaction can be carried out either in a batch system or a continuous system.

The oxathiazines (2) thus obtained include, for example, 6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-
Dioxide, 6-ethyl-3,4-dihydro-1,
2,3-oxathiazin-4-one-2,2-dioxide, 6-n-propyl-3,4-dihydro-1,2,2
3-oxathiazin-4-one-2,2-dioxide, 6-i-propyl-3,4-dihydro-1,2,3
6-C _1-4 alkyl-3,4-dihydro-1,2,2, such as -oxathiazin-4-one-2,2-dioxide.
6-aryl-3 such as 3-oxathiazin-4-one-2,2-dioxide; 6-phenyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide. , 4-Dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide; 5-methyl-6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one- 5,6-diC _1-4 such as 2,2-dioxide, 5-methyl-6-ethyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide Alkyl-3,4-dihydro-1,
2,3-oxathiazin-4-one-2,2-dioxide; 5-phenyl-6-methyl-3,4-dihydro-
5-aryl-6-C _1-4 alkyl- such as 1,2,3-oxathiazin-4-one-2,2-dioxide
3,4-dihydro-1,2,3-oxathiazine-4-
On-2,2-dioxide; 5-methyl-6-phenyl-3,4-dihydro-1,2,3-oxathiazine-
5-C _1-4 alkyl-6-aryl-3,4-dihydro-1,2,3- such as 4-one-2,2-dioxide
Oxathiazin-4-one-2,2-dioxide; 6
-Cyclopentyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide, 6-
6 such as cyclohexyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide;
—C _3-8 cycloalkyl-3,4-dihydro-1,2,2
3-oxathiazin-4-one-2,2-dioxide; 5-cyclopentyl-6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-
Dioxide, 5-cyclohexyl-6-methyl-3,
4-dihydro-1,2,3-oxathiazine-4-one-2,2-5-C _3-8, such as dioxide cycloalkyl -6-C _1-4 alkyl-3,4-dihydro-1,2 ,
3-oxathiazin-4-one-2,2-dioxide; 5-methyl-6-cyclopentyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-
Dioxide, 5-methyl-6-cyclohexyl-3,
5-C _1-4 alkyl-6 such as 4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide
—C _3-8 cycloalkyl-3,4-dihydro-1,2,2
6 such as 3-oxathiazin-4-one-2,2-dioxide; 6-vinyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide;
—C _2-4 alkenyl-3,4-dihydro-1,2,3-
Oxathiazin-4-one-2,2-dioxide; 6
6-C such as -acetyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide
_2-6 acyl-3,4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide and salts thereof.

In particular, oxathiazines wherein R ¹ is a methyl group in the above formula (2) (for example, 6-methyl-3,
4-Dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide) is part of its physiologically acceptable salts (eg, salts with Na, K, Ca, etc.). It is preferred because it is used as a sweetener in the food industry.
Among them, a salt with potassium is particularly useful as acesulfame (acesulfame K).

After completion of the reaction, the obtained oxathiazines are separated and purified by conventional means such as distillation, concentration, extraction,
It can be easily separated and purified by recrystallization, chromatography and the like. For example, ice or water (for example, ice or water in an amount of about 1 to 10 times the amount of the halogenating reagent) is added to the reaction mixture after the completion of the reaction, and the mixture is separated into an organic layer and an aqueous layer. Oxathiazine remaining in the aqueous layer is extracted by adding a solvent (eg, an ester of an organic mono- or dicarboxylic acid (eg, esters exemplified in the above-mentioned reaction solvent)) that is incompatible (or immiscible) with water. , May be collected. The organic layer containing oxathiazine (including the extract from the aqueous layer) may be dried with a conventional drying agent (such as sodium sulfate) and then concentrated, or may be concentrated without drying. After the concentration, if necessary, the product may be further purified by recrystallization or the like.

In the oxathiazines obtained,
In the formula (2), a salt of an oxathiazine which is an organic group or an inorganic metal atom in which R ³ is bonded to a nitrogen atom to form a salt is obtained by converting an oxathiazine in which R ³ is a hydrogen atom in the formula (2); It may be produced by neutralization with a base.

As the base used for neutralization, an organic base corresponding to the organic group which forms a salt by binding to the nitrogen atom [for example, alkylamine (C _1-10 alkylamine, etc.),
Cycloalkylamines (such as C _3-12 cycloalkyl amine) (such as C _{6- 10} aryl amines) arylamine,
And aralkylamines (such as benzylamine)], inorganic bases corresponding to the inorganic metal atoms (eg, hydroxides of the aforementioned inorganic metals, carbonates or bicarbonates of the aforementioned inorganic metals), and the like. Among them, hydroxides of alkali metals such as Na and K (sodium hydroxide, potassium hydroxide, etc.),
Preferred are carbonates (such as sodium carbonate and potassium carbonate) and hydrogen carbonates (such as sodium hydrogen carbonate and potassium hydrogen carbonate).

Oxathiazines (3,4-dihydro-1,2,3-oxathiazines) thus obtained
Is a physiologically acceptable salt (such as potassium salt)
Useful as a sweetener in the food industry.

[0040]

According to the present invention, since a halogen-containing phosphorus compound having a dehydrating property is used as the cyclizing dehydrating agent, it is relatively easy to handle and oxathiazines can be industrially advantageously produced.

[0041]

EXAMPLES The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 1 m of phosphorus oxychloride (POCl ₃ ) was added to 0.48 g of triethylammonium acetoacetamide-N-sulfonate.
was added and stirred at room temperature for 1 hour. After stirring, the reaction solution is concentrated under reduced pressure to remove phosphorus oxychloride, whereby the desired 6-methyl-3,4-dihydro-1,2,3-
Oxthiazin-4-one-2,2-dioxide was obtained.

Example 2 Phosphorus pentachloride (1.25 g) was suspended in methylene chloride (10 ml), cooled to -30 ° C., and then triethylammonium acetoacetamido-N-sulfonate (1.4) under a nitrogen stream.
A solution of 1 g of methylene chloride in 10 ml was added dropwise over 30 minutes. After the dropwise addition, the mixture was further stirred at -30 ° C for 1 hour, and then 10 ml of water was added to separate into an organic layer and an aqueous layer. The organic layer is washed with a saturated aqueous solution of sodium hydrogen carbonate, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to give the desired 6-methyl-3,4-dihydro-1,2,3-
Oxthiazin-4-one-2,2-dioxide was obtained.

Continued on the front page (72) Inventor Ikuo Takahashi 2-7-4 Nakano, Nishi-ku, Kobe-shi, Hyogo F-term (reference) 4H039 CA42 CG10 CH10

Claims (8)

[Claims] [Claim 1] The following formula (1) (Wherein R ¹ and R ² are the same or different and each represent a hydrogen atom or a reaction-inactive organic group, and R ³ binds to a hydrogen atom, a reaction-inactive organic group, or a nitrogen atom to form a salt. X represents an organic group or an inorganic metal atom to be formed, X represents a hydrogen atom or a base which forms a salt with a sulfonate group), and subjected to a cyclization dehydration reaction to give the following formula (2) 2] Wherein R ¹ , R ² and R ³ are the same as defined above, wherein the cyclization dehydration reaction is carried out in the presence of a dehydrating halogen-containing phosphorus compound. A method for producing oxathiazines. 2. The method according to claim 1, wherein the halogen-containing phosphorus compound is at least one selected from phosphorus halides and phosphorus oxyhalides. 3. The process according to claim 1, wherein the halogen-containing phosphorus compound is used in a proportion of 1 to 20 mol per 1 mol of the sulfonic acids of the formula (1). 4. In the formulas (1) and (2), R ¹ and R ² represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an acyl group, an aralkyl group,
Or an aryl group, wherein R ³ is a hydrogen atom, an alkyl group,
The production method according to claim 1, wherein the production method is an alkenyl group, an alkynyl group, a cycloalkyl group, an acyl group, an aralkyl group, an aryl group, or an organic group or an inorganic metal atom which forms a salt by binding to a nitrogen atom. 5. The method according to claim 1, wherein the sulfonic acid of the formula (1) is acetoacetamide-N-sulfonic acid salt. 6. The production method according to claim 1, wherein the sulfonic acid of the formula (1) is a tertiary ammonium salt of acetoacetamido-N-sulfonic acid. 7. The method according to claim 7, wherein the oxathiazine is 6-methyl-3,
The method according to claim 1, which is 4-dihydro-1,2,3-oxathiazin-4-one-2,2-dioxide or a salt thereof. 8. A cyclizing dehydrating agent for cyclizing and dehydrating a sulfonic acid represented by the formula (1) according to claim 1, wherein the cyclizing dehydrating agent comprises a halogen-containing phosphorus compound having a dehydrating property. Dehydrating agent.