JP2001278856A - Method for producing 1-(phenylsulfonyl)-4-[(tribromomethyl)sulfonyl]benzene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for industrially advantageously producing 1-(phenylsulfonyl)-4-[(tribromomethyl)sulfonyl]benzene. SOLUTION: This method for producing 1-(phenylsulfonyl)-4[(tribromomethyl) sulfonyl]benzene of formula (2) is characterized by oxidizing and brominating 1-(methylthio)-4-(phenylsulfonyl)benzene of formula (1).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl]
It relates to a method for producing benzene. More specifically, the present invention relates to a method for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene having the ability to generate radicals upon irradiation with light.

[0002]

2. Description of the Related Art Conventionally, as a photopolymerization initiator, compounds having a halogen in the molecule, for example, carbon tetrachloride, carbon tetrabromide, hexachloroethane, α, α, α-trichlorotoluene, o-nitro-α, α, α-tribromoacetophenone, o-nitrobenzenesulfenyl chloride, hexabromodimethylsulfoxide, trichloromethylphenylsulfone, tribromomethylphenylsulfone,
Tribromomethyl-p-nitrophenyl sulfone, tetrabromodimethyl sulfone and the like are known.

[0003] Among them, (trihalogenomethyl) phenyl sulfones are useful as initiators for polymerization reactions because they generate radicals upon irradiation with light, and are also useful as antifoggants for silver halide photography. Also,
It is also an important compound as an antibacterial agent against microorganisms.

In particular, 1- (phenylsulfonyl) -4-
[(Tribromomethyl) sulfonyl] benzene can effectively utilize the spectrum of a mercury lamp, and is useful as a photopolymerization initiator having high radical generation efficiency.

As a method for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene, for example, 4- (phenylsulfonyl) benzenethiol is reacted with methyl halide to carry out methylthiolation. To give 1- (methylthio) -4- (phenylsulfonyl) benzene,
(Methylsulfonyl) -4- (phenylsulfonyl) benzene, followed by bromination to give 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl]
Methods for obtaining benzene and the like are known.

[0006] However, in the above method, when producing 4- (phenylsulfonyl) benzenethiol as a starting material, 1-halogeno-4- (phenylsulfonyl) is used.
Benzene and sodium bisulfide are reacted in a polar solvent such as N, N-dimethylformamide, but the reaction yield is low and disulfide is produced as a by-product, so that it is necessary to reduce it.

In the step of producing 1- (methylsulfonyl) -4- (phenylsulfonyl) benzene by oxidizing 1- (methylthio) -4- (phenylsulfonyl) benzene, the reaction is carried out in the presence of an acid catalyst. A method using various oxidizing agents such as hydrogen oxide, a method using various oxidizing agents in an acetic acid solvent in the presence of an acid catalyst, and the like are known, all of which are reactions under acidic conditions. On the other hand, the step of brominating 1- (methylsulfonyl) -4- (phenylsulfonyl) benzene is performed under alkaline conditions. Therefore, after completion of the oxidation reaction, 1- (methylsulfonyl) -4
A process for removing or neutralizing-(phenylsulfonyl) benzene is required, and the process is complicated.

[0008]

An object of the present invention is to provide a process for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene in an industrially advantageous manner.

[0009]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that 1- (methylthio) -4- (phenylsulfonyl) benzene is oxidized and brominated. As a result, 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene was industrially advantageously obtained.

That is, the present invention provides the following formula (1):

[0011]

Embedded image

Oxidizing and brominating 1- (methylthio) -4- (phenylsulfonyl) benzene represented by the following formula (2):

[0013]

Embedded image

1- (phenylsulfonyl)-
The present invention relates to a method for producing 4-[(tribromomethyl) sulfonyl] benzene.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, 1- (methylthio) -4- (phenylsulfonyl) benzene is oxidized and brominated to form 1- (phenylsulfonyl) benzene.
4-[(tribromomethyl) sulfonyl] benzene can be produced.

The method of oxidizing and brominating the 1- (methylthio) -4- (phenylsulfonyl) benzene includes (A) a method of simultaneously performing oxidation and bromination using bromine in the presence of a base and water; (B) A method of simultaneously performing oxidation and bromination using hypobromite.

The amount of bromine used in the method (A) for simultaneously performing oxidation and bromination using bromine in the presence of a base and water is 1- (methylthio) -4- (phenylsulfonyl) benzene. On the other hand, 5 to 20 times mol,
Preferably it is 6 to 15 times mol. If the amount of bromine used is less than 5 moles, the reaction is difficult to complete, and if it exceeds 20 moles, there is no effect corresponding to the amount used and it is economically disadvantageous.

The base is not particularly limited.
Examples include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. The amount of the base to be used is generally 2 to 8 moles, preferably 2.1 to 5 moles relative to bromine. If the amount of the base used is less than 2 moles, the reaction is difficult to complete, and if it exceeds 8 moles, there is no effect corresponding to the amount used and it is economically disadvantageous.

The amount of the water used is not particularly limited.
The amount is about 40 to 800 g per 1 mol of the base.

The hypobromite used in the method (B) for simultaneously oxidizing and brominating using hypobromite is not particularly limited, but sodium hypobromite, hypobromite Examples thereof include alkali metal salts of hypobromous acid such as potassium. Among them, sodium hypobromite is preferably used.

The amount of the hypobromite used is 5 to 20 times, preferably 6 to 15 times the mol of 1- (methylthio) -4- (phenylsulfonyl) benzene. If the amount of hypobromite used is less than 5 moles, the reaction is difficult to complete, and if it exceeds 20 moles, there is no effect corresponding to the amount used and it is economically disadvantageous.

The hypobromite is usually used as an aqueous solution, and its concentration is not particularly limited, but industrially, 10 to 30% by weight can be advantageously used.

The reaction temperature in the methods (A) and (B) is usually 5 to 80 ° C., preferably 10 to 75 ° C. in each case. When the reaction temperature is less than 5 ° C,
When the reaction rate is slow and the reaction requires a long time, and when the reaction temperature exceeds 80 ° C., the reaction rate increases but the amount of by-products increases. The reaction time varies depending on the reaction temperature, but usually ranges from 5 to 5.
24 hours.

In the above methods (A) and (B), the reaction usually proceeds in a heterogeneous system, so that the reaction can be smoothly advanced by adding a phase transfer catalyst. The phase transfer catalyst is not particularly limited, but quaternary ammonium salts such as tetrabutylammonium chloride and tetrabutylammonium bromide, and quaternary phosphonium salts such as tetrabutylphosphonium chloride and tetrabutylphosphonium bromide are preferably used. Can be The amount used is usually 0.1 to 50 relative to 1- (methylthio) -4- (phenylsulfonyl) benzene.
% By weight.

In the methods (A) and (B), the starting material 1- (methylthio) -4- (phenylsulfonyl) benzene and the product 1- (phenylsulfonyl) -4-[(tribromo Because both methyl) sulfonyl] benzene are water-insoluble, the oxidation and bromination reactions take place in a solid-liquid heterogeneous two-phase system. Therefore, after the completion of the reaction, 1-
(Phenylsulfonyl) -4-[(tribromomethyl)
Sulfonyl] benzene can be isolated. Also,
Using an organic solvent such as monochlorobenzene or dichlorobenzene, the oxidation and bromination reaction can be carried out in a liquid-liquid heterogeneous two-phase system. At that time, after completion of the reaction, an organic layer is obtained by a liquid separation operation, and the obtained organic layer is cooled to obtain 1
-(Phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene can also be precipitated and isolated. The appropriate amount of the organic solvent is 50 to 2000 g per 1 mol of 1- (methylthio) -4- (phenylsulfonyl) benzene.

The method for producing 1- (methylthio) -4- (phenylsulfonyl) benzene used as a raw material in the production method of the present invention is not particularly limited, but for example, the following general formula (3):

[0027]

Embedded image (In the formula, X represents a halogen atom.)

And the method of reacting 1-halogeno-4- (phenylsulfonyl) benzene and an alkali metal salt of methanethiol.

Here, 1- represented by the general formula (3) is used.
Halogeno-4- (phenylsulfonyl) benzene can be produced by a method of reacting monohalogenobenzene with benzenesulfonyl chloride under a Lewis acid catalyst. Specific examples of the 1-halogeno-4- (phenylsulfonyl) benzene include, for example, 1-fluoro-
4- (phenylsulfonyl) benzene, 1-chloro-4
-(Phenylsulfonyl) benzene, 1-bromo-4-
(Phenylsulfonyl) benzene and 1-iodo-4
— (Phenylsulfonyl) benzene and the like. Among them, 1-chloro-4- (phenylsulfonyl) benzene is preferably used.

The alkali metal salt of methanethiol used in the reaction between the above-mentioned 1-halogeno-4- (phenylsulfonyl) benzene and the alkali metal salt of methanethiol is not particularly limited, but potassium methanethiolate, sodium methanethiol, etc. Rate and the like. Among them, sodium methanethiolate is preferably used.
The amount of the alkali metal salt of methanethiol used is based on 1-halogeno-4- (phenylsulfonyl) benzene.
Usually, it is 1 to 3 moles, preferably 1 to 2 moles, more preferably 1.1 to 1.5 moles. When the use amount of the alkali metal salt of methanethiol is less than 1 mole, unreacted 1-halogeno-4- (phenylsulfonyl) benzene increases, and when it exceeds 3 moles, an effect commensurate with the use amount is obtained. Economically disadvantageous.

The alkali metal salt of methanethiol is
Usually, it is used as an aqueous solution, and its concentration is 5 to 60% by weight, preferably 10 to 40% by weight.

In the above reaction, since the reaction usually proceeds in a heterogeneous system, a phase transfer catalyst can be added to allow the reaction to proceed smoothly. As the phase transfer catalyst,
Although not particularly limited, quaternary ammonium salts such as tetrabutylammonium chloride and tetrabutylammonium bromide, and quaternary phosphonium salts such as tetrabutylphosphonium chloride and tetrabutylphosphonium bromide are preferably used. Its usage is 1
It is usually 0.1 to 50% by weight based on -halogeno-4- (phenylsulfonyl) benzene. When the use amount of the phase transfer catalyst is less than 0.1% by weight, the catalytic effect is not sufficiently exhibited, and when it exceeds 50% by weight, the effect corresponding thereto cannot be obtained, which is economically disadvantageous.

The reaction temperature in the above reaction is usually 50
To 120 ° C, preferably 75 to 110 ° C. When the reaction temperature is lower than 50 ° C., the reaction rate is slow and the reaction takes a long time. The reaction time varies depending on the reaction temperature, but is usually 1 to 10 hours.

In the above reaction, since the starting material 1-halogeno-4- (phenylsulfonyl) benzene is insoluble in water, the reaction temperature is lower than the melting point of 1-halogeno-4- (phenylsulfonyl) benzene. Proceeds in a solid-liquid heterogeneous two-phase system, and when the reaction temperature is equal to or higher than the melting point of 1-halogeno-4- (phenylsulfonyl) benzene, the reaction proceeds in a liquid-liquid heterogeneous two-phase system. proceed. Since the product, 1- (methylthio) -4- (phenylsulfonyl) benzene, is also insoluble in water, the reaction solution is cooled after completion of the reaction, so that 1- (methylthio) -4 can be easily obtained only by ordinary filtration. -(Phenylsulfonyl) benzene can be isolated. The reaction can also be carried out in a liquid-liquid heterogeneous two-phase system using an organic solvent in which 1-halogeno-4- (phenylsulfonyl) benzene such as monochlorobenzene and dichlorobenzene is dissolved. At that time, after completion of the reaction, an organic layer is obtained by a usual liquid separation operation, and the obtained organic layer is cooled to obtain 1- (methylthio)-.
4- (phenylsulfonyl) benzene can be isolated by precipitation. The appropriate amount of the organic solvent used is 500 to 2000 g per 1 mol of 1-halogeno-4- (phenylsulfonyl) benzene.

In the present invention, 1- (methylthio)-
Using a reaction solution containing 4- (phenylsulfonyl) benzene, followed by oxidation and bromination,
(Phenylsulfonyl) -4-[(tribromomethyl)
Sulfonyl] benzene can also be produced in one pot.

[0036]

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

Example 1 A 0. 1 was equipped with a stirrer, thermometer, cooler and dropping funnel.
A 5-L four-necked flask is charged with 15.3 g (0.1 mol) of 1-chloro-4- (phenylsulfonyl) benzene, 2.0 g of tetrabutylammonium bromide and 80 g of monochlorobenzene, and is heated at 80 to 90 ° C. for 1 hour. And a 30% by weight aqueous solution of sodium methanethiolate 3
5.0 g (0.15 mol) was added dropwise, and after the addition, 90-1
The reaction was performed at 00 ° C. for 3 hours.

After completion of the reaction, the obtained reaction solution was separated at 85 ° C. to obtain an organic layer. The obtained organic layer was cooled, and the precipitated product was filtered, washed and dried to obtain 1- ( Methylthio)-
23.8 g of 4- (phenylsulfonyl) benzene (0.
09 mol). The yield based on 1-chloro-4- (phenylsulfonyl) benzene was 90.0%.

Example 2 1-chloro-4- (phenylsulfonyl) was placed in a 0.5 L four-necked flask equipped with a stirrer, a thermometer and a condenser.
25.3 g (0.1 mol) of benzene, 2.5 g of tetrabutylammonium bromide and 56.1 g (0.12 mol) of a 15% by weight aqueous solution of sodium methanethiolate
, And the temperature was raised to 95 ° C. over 1 hour,
After the temperature was raised, the reaction was performed at 95 to 100 ° C for 2 hours.

After the completion of the reaction, the obtained reaction solution was cooled, and the precipitated product was filtered, washed, and dried to obtain 25.4 g of 1- (methylthio) -4- (phenylsulfonyl) benzene.
(0.096 mol). The yield based on 1-chloro-4- (phenylsulfonyl) benzene was 96.0%.

Example 3 A 27% by weight aqueous solution of sodium hypobromite 2 was placed in a 0.5 L four-necked flask equipped with a stirrer, a thermometer and a cooler.
1- (methylthio) -4 obtained by the method of Example 1 was charged with 64.2 g (0.6 mol) and 2 g of tetrabutylammonium bromide and required 1 hour at 30 to 40 ° C.
-(Phenylsulfonyl) benzene 25.1 (0.09
5 mol), and reacted at 40-50 ° C. for 8 hours after the addition.

After completion of the reaction, the precipitated product was filtered, washed and dried, and 41.6 g of 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene was obtained.
(0.078 mol). 1- (methylthio) -4-
87% yield based on (phenylsulfonyl) benzene
Met.

Example 4 A 0. 0 equipped with a stirrer, thermometer, cooler and dropping funnel.
A 1 L obtained by the method of Example 2 was placed in a 5 L four-necked flask.
-(Methylthio) -4- (phenylsulfonyl) benzene 25.4 g (0.096 mol), sodium hydroxide 8
0 g (2.0 mol) and 200 g of water were charged.
111.9 g (0.7 mol) of bromine in 4 hours at 30
Was dropped, and reacted at 40 to 50 ° C. for 6 hours.

After completion of the reaction, the precipitated product was filtered, washed and dried to give 1- (phenylsulfonyl) -4-.
[(Tribromomethyl) sulfonyl] benzene 45.3
g (0.085 mol) were obtained. 1- (methylthio) -4
The yield based on-(phenylsulfonyl) benzene is 8
8.5%.

Example 5 A 0. 0 provided with a stirrer, thermometer, cooler and dropping funnel.
A 5-L four-necked flask is charged with 15.3 g (0.1 mol) of 1-chloro-4- (phenylsulfonyl) benzene, 2.0 g of tetrabutylammonium bromide and 80 g of monochlorobenzene, and is heated at 80 to 90 ° C. for 1 hour. And a 30% by weight aqueous solution of sodium methanethiolate 3
5.0 g (0.15 mol) was added dropwise, and after the addition, 90-1
The reaction was performed at 00 ° C. for 3 hours. 80 g (2.0 mol) of sodium hydroxide and 200 g of water are charged to the obtained reaction solution, and 111.9 g of bromine is required at 30 to 40 for 4 hours.
(0.7 mol) was added dropwise, and after the addition, 10 to 40 ° C to 50 ° C.
Allowed to react for hours.

After completion of the reaction, the precipitated product was filtered, washed and dried to give 1- (phenylsulfonyl) -4-.
[(Tribromomethyl) sulfonyl] benzene 46.4
g (0.087 mol). The yield based on 1-chloro-4- (phenylsulfonyl) benzene was 87%.

Example 6 1-chloro-4- (phenylsulfonyl) was placed in a 0.5 L four-necked flask equipped with a stirrer, a thermometer and a condenser.
25.3 g (0.1 mol) of benzene, 2.5 g of tetrabutylammonium bromide and 56.1 g (0.12 mol) of a 15% by weight aqueous solution of sodium methanethiolate
, And the temperature was raised to 95 ° C. over 1 hour,
After the temperature was raised, the reaction was performed at 95 to 100 ° C for 2 hours. A 27% by weight aqueous solution of sodium hypobromite 26 was added to the obtained reaction solution.
4.2 g (0.6 mol) was added to 50-60 over 2 hours.
The reaction was carried out at 60 to 70 ° C. for 7 hours.

After completion of the reaction, the obtained reaction solution was cooled, and the precipitated product was filtered, washed and dried to obtain 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl].
47.4 g (0.089 mol) of benzene were obtained. The yield based on 1-chloro-4- (phenylsulfonyl) benzene was 89%.

[0049]

According to the present invention, 1- (phenylsulfonyl) -4-yl which can effectively utilize the spectrum of a mercury lamp and is useful as a photopolymerization initiator having high radical generation efficiency.
[(Tribromomethyl) sulfonyl] benzene can be industrially advantageously produced.

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Claims (9)

[Claims] (1) The following formula (1): Oxidizing and brominating 1- (methylthio) -4- (phenylsulfonyl) benzene represented by the following formula (2): A method for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene represented by the formula: 2. The process for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene according to claim 1, which is oxidized and brominated with bromine in the presence of a base and water. 3. The method for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene according to claim 2, wherein the base is an alkali metal hydroxide. 4. The 1- (phenylsulfonyl) -4- according to claim 1, which is oxidized and brominated using hypobromite.
A method for producing [(tribromomethyl) sulfonyl] benzene. 5. The 1- (phenylsulfonyl) -4- according to claim 4, wherein the hypobromite is sodium hypobromite.
A method for producing [(tribromomethyl) sulfonyl] benzene. 6. A compound represented by the following general formula (3): (Where X represents a halogen atom) 1- (methylthio) -4, characterized by reacting 1-halogeno-4- (phenylsulfonyl) benzene represented by the formula (1) with an alkali metal salt of methanethiol: -(Phenylsulfonyl)
Method for producing benzene. 7. The 1- (methylthio) according to claim 6, wherein the 1-halogeno-4- (phenylsulfonyl) benzene is 1-chloro-4- (phenylsulfonyl) benzene.
A method for producing 4- (phenylsulfonyl) benzene. 8. The method for producing 1- (methylthio) -4- (phenylsulfonyl) benzene according to claim 6, wherein the alkali metal salt of methanethiol is sodium methanethiolate. 9. A compound represented by the following general formula (3): (Wherein X represents a halogen atom.) 1-halogeno-4- (phenylsulfonyl) benzene represented by the following formula (1) is reacted with an alkali metal salt of methanethiol: 1- (methylthio) -4- (phenylsulfonyl) benzene represented by the following formula (2), which is subsequently oxidized and brominated; A method for producing 1- (phenylsulfonyl) -4-[(tribromomethyl) sulfonyl] benzene represented by the formula: