JPH07138195A - Production of allyl bromides - Google Patents

Abstract

PURPOSE:To efficiently obtain an allyl bromides useful as an intermediate for producing agrochemicals and medicines, dyes, etc., in a high yield and selectivity by reacting a specific allyl chloride with a metal bromide in the presence of a specific compound. CONSTITUTION:An allyl chloride of formula I (R, R1 and R2 are each H or a lower alkyl) is reacted with a metal bromide such as sodium bromide in the presence of (A) water, (B) a phase-transfer catalyst such as quaternary ammonium salts and (C) a basic compound such as (heavy) carbonic acid salt of an alkali (alkaline earth) metal to obtain the objective compound of formula II.

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 allyl bromides which is useful in the field of synthetic organic chemistry, particularly as an intermediate in the production of fine chemical products such as agricultural drugs and dyes. More specifically, it relates to an improved production method of allyl bromides by a halogen exchange reaction using allyl chlorides as a raw material.

[0002]

2. Description of the Related Art Formula (2) (Formula 3)

[0003]

[Chemical 3]

Various methods have been disclosed as methods for producing allyl bromides represented by the formula (wherein R, R ₁ and R ₂ each independently represent a hydrogen atom or a lower alkyl group). Looking at the known production method for allyl bromide (R = R1 = R2 = H} in the formula (2), which is the basic compound of the formula (2), generally, allyl alcohol is generally added to hydrogen bromide in the presence of sulfuric acid. It is produced by reacting with an acid.

For example, organic synthesis {Or
ganic Synthesis, Coll. , Volume 1,
According to p. 27 (1976)}, 5.9 mol of 48% hydrobromic acid and 4 mol of allyl alcohol are mixed, and 300 g of agricultural sulfuric acid is gradually added to this aqueous solution with stirring, followed by distillation. By doing so, allyl bromide can be obtained. According to this method, the target allyl bromide is 92
Although it can be produced in a quantitatively close yield of up to 96%, a large amount of acid wastewater is industrially generated due to the use of a large amount of sulfuric acid, and an operation such as neutralization treatment is required and the cost increases. It has drawbacks such as

Also known is a method for producing allyl bromide by brominating propylene with hydrogen bromide at a high temperature (350 to 450 ° C.) in the presence of pearlite catalyst (Soviet Patent No. 753,841 (1980)). However, this method not only has a low selectivity to allyl bromide due to by-product of 1-bromopropene, but also has a problem in separation from by-products.

On the other hand, a method for producing allyl bromides by a halogen exchange reaction of allyl chlorides is also known. Journal of the Organic Chemistry {J
individual of the Organic Cem
story USSR Volume 10, 1122 (1974
)}, Allyl bromide or methallyl bromide is produced by subjecting allyl chloride or methallyl chloride to halogen exchange reaction with excess hydrobromic acid in the presence of cuprous chloride.

[0008] The Journal of the American Chemical Society {Jo-urnal of
the American Chemical Soc
eity, 72, p. 4316 (1950)}, methallyl chloride is subjected to a halogen exchange reaction with sodium bromide in methanol to give methallyl bromide, and methallyl bromide with lithium bromide in acetone. A method of doing so is disclosed.

However, the former method not only has a low conversion rate of methallyl chloride of 70% or less, but requires special attention to wastewater measures because a heavy metal compound subject to industrial regulation is used as a catalyst. And have to. Even with the latter method, the yield of methallyl bromide is only 54%.

Regarding the halogen exchange reaction of an alkyl chloride to an alkyl bromide with a metal bromide using a phase transfer catalyst and water, conventionally, a synthesis {SYNT
H-ESIS 1 Vol. 34-5 (1984)} and Journal of the Chemical Society.
Chemical Communications {Journalof
the Chemical Society Che
medical Communications, 1250
Page (1986)}, allyl bromide, which is the method of the present invention, for carrying out the reaction of allyl chlorides with metal bromides in the presence of a small amount of water and a phase transfer catalyst. There is no known method for producing such a kind.

As a method for producing allyl bromides, some methods other than the above-mentioned methods are known, but none is satisfactory in terms of raw material or yield. The present applicants have previously proposed a method of reacting allyl chlorides with a metal bromide in an aprotic polar solvent to produce the corresponding allyl bromides in good yield (Japanese Patent Laid-Open No. 3-1 / 1993).
69830). However, it cannot be said that the method proposed by the present applicants is a sufficient method from an industrial viewpoint, and it has the following problems.

That is, it is necessary to use an aprotic polar solvent as a reaction solvent, and it is industrially necessary to recover and reuse this reaction solvent. In addition, there is a problem that it is difficult to apply to the production of allyl bromides having the same boiling point as that of the aprotic polar reaction solvent. Therefore, improvement of these problems is required.

[0013]

The present invention has been made in order to solve the problems of the above-mentioned conventional techniques, and is used in the field of synthetic organic chemistry, especially in the production of agricultural drugs and dyes. Formula (2) (Chemical Formula 4) useful as an intermediate

[0014]

[Chemical 4]

For the purpose of providing an improved and more industrial process for producing allyl bromides of the formula: wherein R, R ₁ and R ₂ each independently represent a hydrogen atom or a lower alkyl group. There is.

As a result of intensive studies conducted by the present inventors to solve the problems of the prior art, based on the findings of the present inventors, allyl halides, especially allyl bromides, are heated in the presence of water. Then, even though the compounds are susceptible to hydrolysis and easily converted into allyl alcohols and the like, the halogen exchange reaction between the allyl chlorides and the metal bromide is carried out in the presence of a small amount of water and a phase transfer catalyst. By carrying out, it is possible to produce the target allyl bromides with a high conversion rate and a high yield, and the metal bromide is insoluble in allyl chlorides, in a reaction system in which water and a phase transfer catalyst are not present. However, the halogen exchange reaction does not proceed at all.

On the other hand, even in the reaction system to which water is added, when the phase transfer catalyst is not present, a small amount of the allyl bromide is produced, but the conversion rate of the allyl chloride is low. Also, in the presence of a phase transfer catalyst, the conversion rate was similarly low in a reaction system in which water was not present, and it was discovered that a proper range of water content was necessary to obtain a sufficient conversion rate, and so on. As a result, the method for producing allyl bromides (Japanese Patent Application No. 5-111326), which incorporates the method for preventing the solidification of metal bromide during the reaction as a method for improving the method (Japanese Patent Application No. 5-111326). Wishhei 5-
) Was proposed earlier.

However, in the subsequent studies, during the reaction for producing the corresponding allyl bromides from allyl chlorides, the starting allyl chlorides and a part of the produced allyl bromides were decomposed, and the reaction mass was considerably reduced. We obtained new knowledge that it becomes acidic. Since the reaction mass is acidic, when carrying out the reaction industrially, it is necessary to use an expensive acid-resistant reaction vessel or auxiliary equipment.

[0019]

The inventors of the present invention have conducted extensive studies thereafter, and as a result, by adding a certain base sufficient to neutralize the acidic components generated in the reaction system, the reaction mass The inventors have found that the target allyl bromides can be produced without deteriorating the reaction results, while maintaining the neutrality to weak basicity of the compound, and completed the present invention. That is, the present invention uses the formula (1)

[0020]

[Chemical 5]

(In the formula, R, R ₁ and R ₂ each independently represent a hydrogen atom or a lower alkyl group.) In the presence of water, a phase transfer catalyst and a basic compound, allyl chlorides represented by , Formula (2) characterized by reacting with a metal bromide

[0022]

[Chemical 6]

(Wherein R, R ₁ and R ₂ each independently represents a hydrogen atom or a lower alkyl group) is a method for producing an allyl bromide.

The method of the present invention is an industrially excellent production method, and according to the method of the present invention, allyl chlorides can be reacted with high volumetric efficiency under relatively mild conditions. It is possible, and allyl bromides can be produced with high conversion and high yield. Also, after the reaction, the desired product can be isolated by adding water to the reaction mixture after completion of the reaction to dissolve the inorganic salt, and then obtaining a relatively high-purity allyl bromide only by a liquid separation operation. Highly pure allyl bromides can be obtained by performing distillation purification according to the above.

The allyl bromides obtained by the present invention have a high quality which can be sufficiently used as a useful intermediate for the production of synthetic organic chemistry, particularly agricultural medicine and dyes.
The method of the present invention will be described below.

In the present invention, the allyl chlorides of the formula (1) are used as raw materials. Specifically, allyl chloride, methallyl chloride, γ-methylallyl chloride,
γ, γ-dimethylallyl chloride, β-methyl-γ, γ
-Dimethylallyl chloride, γ-ethyl allyl chloride, γ-n-propyl allyl chloride, γ-isopropyl allyl chloride, γ-n-butyl allyl chloride, γ
-Sec-Butyl allyl chloride, γ-iso-butyl allyl chloride, γ-tertiary butyl allyl chloride and the like can be mentioned.

The metal bromide used as the halogen exchange agent for the allyl chlorides of the formula (1) is not particularly limited as long as it is a metal bromide, and specifically, lithium bromide, sodium bromide, potassium bromide, bromide. Calcium, ferrous bromide,
Although ferric bromide, cupric bromide, rubidium bromide and the like can be mentioned, industrially, sodium bromide is preferable.

Although the amount of the metal bromide used is less than the stoichiometric amount, it is of course possible to react, but in consideration of the conversion rate of allyl chloride as a raw material and the yield of allyl bromide as a target product, the formula (1) is usually used. It is suitable to use more than the theoretical amount for allyl chlorides. The upper limit of the amount used is preferably not more than 2 times the molar amount of allyl chloride as a raw material, from the viewpoint of stirring efficiency and economical efficiency.

The method of the present invention is characterized in that the reaction of allyl chlorides with metal bromide is carried out in the presence of a small amount of water, a phase transfer catalyst and a basic compound.
If the amount of water added to the reaction system is too small, the reaction progresses remarkably slowly, and if it is too large, the yield decreases. The amount of water used was 0.
1 to 30% by weight, more preferably 0.5 to 20%
%, Particularly preferably 2 to 15% by weight.

Any type of phase transfer catalyst may be used as long as it is a compound having a property of transferring bromine anions to an organic phase, such as quaternary ammonium salts, phosphonium salts, macrocyclic polyethers and chain polyethers. The compound (4) is not particularly limited, but quaternary ammonium salts are preferable from the economical point of view. Examples of quaternary ammonium salts include tetrabutylammonium bromide, tetrabutylammonium chloride, tetrahexylammonium bromide, tetrahexylammonium chloride, benzyltributylammonium bromide, benzyltributylammonium chloride, etc., but of course these compounds are not the only examples. It is not something that will be done. The upper limit of the amount of the phase transfer catalyst used is not particularly limited, but the smaller amount is preferable from the economical viewpoint, and the amount is 0.1 to 20% by weight based on the allyl chloride.
Is suitable, and a range of 0.5 to 10% by weight is more preferable.

In the method of the present invention, the halogen exchange reaction is carried out in the presence of a basic compound. The basic compound is not particularly limited as long as it is a compound that does not adversely affect the halogen exchange reaction,
Usually an alkali metal or alkaline earth metal carbonate,
Inorganic basic compounds such as bicarbonates, phosphates or hydrogen phosphates, or organic basic compounds such as tertiary amines are used.

Specifically, as the inorganic basic compound, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, lithium carbonate, lithium bicarbonate,
Rubidium carbonate, rubidium bicarbonate, strontium carbonate, strontium bicarbonate, calcium carbonate, barium carbonate, magnesium carbonate, disodium hydrogen phosphate,
Examples include monosodium hydrogen phosphate, dipotassium hydrogen phosphate, and monopotassium hydrogen phosphate. In addition, examples of the organic base compound include tertiary amines such as pyridine, trimethylamine, triethylamine, tripropylamine and tributylamine. Inorganic base compounds preferably used in the method of the present invention are sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, calcium carbonate, barium carbonate, magnesium carbonate, disodium hydrogen phosphate, monosodium hydrogen phosphate, hydrogen phosphate. Examples thereof include dipotassium and monopotassium hydrogen phosphate, and preferred organic basic compounds include pyridine and triethylamine.

With respect to the amount of the basic compound used, the lower limit of its use may be such that the acidic substance generated during the reaction is sufficiently neutralized. Side reactions such as hydrolysis reaction of allyl bromides are easily induced. Therefore, an amount that does not induce alteration of allyl chlorides and allyl bromides may be used, but it is usually used in the range of 0.2% by weight to 10% by weight with respect to the starting material allyl chlorides.

The specific embodiment of the present invention is as follows. After charging a predetermined amount of phase transfer catalyst, a predetermined amount of water, and a predetermined amount of base into a predetermined amount of allyl chlorides, while thoroughly mixing and stirring, gradually add a predetermined amount of metal bromide therein. A predetermined amount of allyl chloride, a predetermined amount of metal bromide and a predetermined amount of base are sufficiently mixed and stirred, and a predetermined amount of water and a phase transfer catalyst mixture is added dropwise thereto. After that, the temperature is raised to a predetermined temperature to carry out the reaction while continuing stirring.

The reaction temperature is not particularly limited as long as it does not deteriorate the allyl chlorides or allyl bromides, but is preferably in the range of 20 to 100 ° C.

As the reaction method, all the raw materials, the phase transfer catalyst and water are charged to react, the metal bromide is charged in a divided manner to react, or the reaction is carried out while allyl chlorides are added dropwise. Various methods such as a method of performing the above can be adopted.

In the present invention, the progress of the reaction can be known by means of gas chromatography or the like. As a method for isolating allyl bromides produced by the above halogen exchange reaction, after the reaction, the reaction mixture is cooled if necessary, by-produced metal chloride, residual metal bromide and phase transfer catalyst, and the added base. The amount of water that dissolves is added, and allyl bromides produced by the liquid separation operation are isolated by a very simple method. In the case of obtaining higher-purity allyl bromides, after separation, metal bromide in an amount corresponding to the residual methallyl chloride, a phase transfer catalyst and water are added and subjected to a halogen exchange reaction again, or the above isolation method. The allyl bromides obtained in step 1 can be purified by distillation, or the unreacted allyl chlorides can be distilled off to leave the allyl bromides in the distillation pot.

As the distillation method, either distillation under normal pressure or vacuum distillation can be used. The unreacted allyl chlorides recovered as the initial distillate can be subjected to the halogen exchange reaction again if necessary.

[0039]

The present invention will be described in more detail with reference to the following examples.

Example 1 In a 500 ml round-bottomed flask equipped with a cooling condenser, 76.5 g (1.0 mol) of allyl chloride and 3.2 g (10 mmol) of tetrabutylammonium bromide.
Then, 3 g of water and 0.8 g of sodium bicarbonate were charged, and 122.4 g (1.2 mol) of sodium bromide was gradually added to the mixture while sufficiently mixing and stirring so as to be homogeneous. . Then, the temperature was raised to 65 ° C. with stirring, and the reaction was performed for 6 hours. After the reaction solution was cooled to 16 ° C., 300 g of water was added to the reaction solution and the layers were separated to obtain 117.1 g of crude allyl bromide as an oily substance. The pH of the aqueous layer after liquid separation was 7.2, which was neutral. As a result of analyzing the obtained crude allyl bromide by gas chromatography,
The production rate of allyl bromide was 93.3% (vs. allyl chloride), and the raw material allyl chloride was 6.4% (vs. charged allyl chloride). There were almost no by-products other than allyl bromide, and allyl bromide was selectively produced. The crude allyl bromide obtained was distilled with a distillation apparatus equipped with a rectification column to give a boiling point of 69.5 to 7
105.5 g (purity 98% or more) of allyl bromide of 1.0 degreeC was obtained. The yield was 87.2% (based on allyl chloride). As the initial distillation, 10.3 g of a mixture of allyl chloride and allyl bromide was obtained.

Example 2 90.6 g (1 mol) of methallyl chloride and 3.2 g (10 mmol) of tetrabutylammonium bromide were placed in a 500 ml round-bottomed flask equipped with a cooling condenser.
And charged with 5 g of water and 1.5 g of potassium carbonate,
122.4 g (1.2 mol) of sodium bromide was gradually added with thorough mixing and stirring so as to be homogeneous. Then, the temperature was raised and the reaction was carried out at 65 ° C. for 6 hours while stirring. After cooling the reaction solution, 300 g of water was added to the reaction solution,
The layers were separated to obtain 131.4 g of crude methallyl bromide as an oily substance. The pH of the aqueous layer after liquid separation was 9.2. When the obtained crude methallyl bromide was analyzed by gas chromatography, the production rate of methallyl bromide was 9
4.1% (vs methallyl chloride), 5.5% of raw material methallyl chloride (vs. charged methallyl chloride)
Was the remaining. There were almost no byproducts other than methallyl bromide, and methallyl bromide was selectively produced.
The crude methallyl bromide obtained was distilled under a reduced pressure of 200 mmHg by a distillation apparatus equipped with a rectification column to give a boiling point of 5
118.9 g of methallyl bromide at 2.0 to 53.0 ° C
(Purity of 98% or more) was obtained. Yield 88.1% (vs methallyl chloride).

Example 3 90.6 g (1 mol) of methallyl chloride and 3.2 g (10 mmol) of tetrabutylammonium bromide were placed in a 500 ml round-bottomed flask equipped with a cooling condenser.
And charged with 5g of water and 1g of calcium carbonate,
122.4 g (1.2 mol) of sodium bromide was gradually added with thorough mixing and stirring so as to be homogeneous. Then, the temperature was raised and the reaction was carried out at 65 ° C. for 6 hours while stirring. After cooling the reaction solution, 300 g of water was added to the reaction solution,
The layers were separated to obtain 131.4 g of crude methallyl bromide as an oily substance. The pH of the aqueous layer after liquid separation was 6.6. When the obtained crude methallyl bromide was analyzed by gas chromatography, the production rate of methallyl bromide was 9
3.8% (relative to methallyl chloride) and 5.7% of raw material methallyl chloride (relative to methallyl chloride)
Was the remaining.

Example 4 9500 g (1 mol) of methallyl chloride and 3.2 g (10 mmol) of tetrabutylammonium bromide were placed in a 500 ml round-bottomed flask equipped with a cooling condenser.
Then, 5 g of water and 1 g of magnesium carbonate were charged, and 122.4 g (1.2 mol) of sodium bromide was gradually added with sufficient mixing and stirring so as to be homogeneous. Then, the temperature was raised and the reaction was carried out at 65 ° C. for 6 hours while stirring. After cooling the reaction solution, 300 g of water was added to the reaction solution and the layers were separated to obtain 131.4 g of crude methallyl bromide as an oily substance. The pH of the aqueous layer after liquid separation was 6.8.
When the obtained crude methallyl bromide was analyzed by gas chromatography, the production rate of methallyl bromide was 93.9% (vs. methallyl chloride), and the raw material methallyl chloride was 5.6% (vs. charged). Of methallyl chloride).

Example 5 90.6 g (1 mol) of methallyl chloride and 3.2 g (10 mmol) of tetrabutylammonium bromide were placed in a 500 ml round-bottomed flask equipped with a cooling condenser.
And 5 g of water and 2 g of pyridine were added, and sodium bromide was added with sufficient stirring to mix them uniformly.
2.4 g (1.2 mol) was added slowly. Then, the temperature was raised and the reaction was carried out at 65 ° C. for 6 hours while stirring. After cooling the reaction solution, 300 g of water was added to the reaction solution and the layers were separated to obtain 131.4 g of crude methallyl bromide as an oily substance. The pH of the aqueous layer after liquid separation was 7.1. When the obtained crude methallyl bromide was analyzed by gas chromatography, the production rate of methallyl bromide was 92.
It was 7% (vs. methallyl chloride), and the raw material methallyl chloride was 6.7% (vs. charged methallyl chloride).

Comparative Example 1 (Reaction under the condition that water was not added) In a 100 ml round bottom flask equipped with a cooling condenser, 24.5 g (0.24 mol) of sodium bromide and 18.0 g (0.2 of methallyl chloride) were added. Mol) and 0.6 g (1.9 mmol) of tetrabutylammonium bromide, and then the reaction was carried out at 65 ° C. for 6 hours while stirring. After cooling the reaction solution, 60 g of water was added to the reaction solution, and the oily matter obtained by liquid separation was analyzed by gas chromatography to find that the production rate of methallyl bromide was 6.
4% (vs methallyl chloride).

Comparative Example 2 (Reaction under the condition that no phase transfer catalyst was added) Sodium bromide 24.5 g (0.24 mol) and methallyl chloride 18.0 g (0) were placed in a 100 ml round bottom flask equipped with a cooling condenser. .2 mol) and water 1.0
After charging g, the reaction was carried out at 65 ° C. for 6 hours while stirring. After cooling the reaction solution, 60 g of water was added to the reaction solution, and the oil obtained by liquid separation was analyzed by gas chromatography to find that the yield of methallyl bromide was 0.68% (versus methallyl chloride). there were.

Comparative Example 3 90.6 g (1 mol) of methallyl chloride and 3.2 g (10 mmol) of tetrabutylammonium bromide were placed in a 500 ml round-bottomed flask equipped with a cooling condenser.
And 5 g of water were charged, and 122.4 g (1.2 mol) of sodium bromide was gradually added with sufficient mixing and stirring so as to be homogeneous. Then, raise the temperature and stir 65
The reaction was carried out at 6 ° C for 6 hours. After cooling the reaction solution,
300 g of water was added to the reaction solution, and the mixture was separated to give 13 as an oil.
1.4 g of crude methallyl bromide was obtained. The pH of the aqueous layer after separation was 1.4. When the obtained crude methallyl bromide was analyzed by gas chromatography, the production rate of methallyl bromide was 93.9% (vs. methallyl chloride), and the raw material methallyl chloride was 5.6% (vs. charged). Of methallyl chloride).

Comparative Example 4 In a 500 ml round bottom flask equipped with a cooling condenser, 122.4 g (1.2 mol) of sodium bromide, 90.6 g (1 mol) of methallyl chloride and 3.2 g of tetrabutylammonium bromide ( (10 mmol), and then 5 g of water was charged with gentle stirring. At the end of the charging of water, it was observed that part of the metal bromide had solidified. After that, the temperature was raised with continuing stirring to carry out a reaction at 65 ° C. for 6 hours. The solidified metal bromide remained as it was during the reaction. After cooling the reaction solution, 300 g of water was added to the reaction solution and the layers were separated to obtain 106.5 g of crude methallyl bromide as an oily substance. At this time, the pH of the aqueous layer was 1.4. When the obtained crude methallyl bromide was analyzed by gas chromatography, the production rate of methallyl bromide was 51.7% (versus methallyl chloride), and the raw material methallyl chloride was 47.1.
% (To the charged methallyl chloride) remained.

Examples 6-8 In Examples 6-8, the amount of water added to the reaction was examined. The other reaction conditions were the same as in Example 2. The results are shown in Table 1 (Table 1).

[0050]

[Table 1]

Examples 9-10 In Examples 9-10, the type of metal bromide added to the reaction was examined. The other reaction conditions were the same as in Example 2. The results are shown in Table 2 (Table 2).

[0052]

[Table 2]

Examples 11 to 12 The kinds of allyl chloride used in the reactions in Examples 11 to 12 were examined. The other reaction conditions were the same as in Example 2. The results are shown in Table 3 (Table 3).

[0054]

[Table 3]

[0055]

EFFECT OF THE INVENTION According to the method of the present invention, allyl chlorides are used as a raw material, without using a solvent, and without using a reaction kettle made of expensive acid-resistant glass lining,
The target allyl bromides can be efficiently converted with high volume efficiency under mild conditions and in high yield. Moreover, since the reaction selectivity is high, the isolation method is sufficient only at room temperature for liquid separation with water. Even in the case of obtaining higher-purity allyl bromides, it is sufficient to remove residual allyl chlorides by distillation under mild conditions,
Easy to isolate and purify. Further, there is an advantage that the mixture of residual allyl chloride and allyl bromide obtained by distillation can be used as it is as a raw material for the halogen exchange reaction. Therefore, the present invention is an industrially valuable method for producing allyl bromides, which are useful synthetic intermediates in the field of synthetic organic chemistry, particularly agricultural medicine and dyes.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryuichi Mita 30 Asamuta-cho, Omuta-shi, Fukuoka Mitsui Toatsu Chemical Co., Ltd.

Claims (4)

[Claims] 1. Formula (1) (Formula 1) (In the formula, R, R ₁ and R ₂ each independently represent a hydrogen atom or a lower alkyl group.), An allyl chloride represented by a metal bromide in the presence of water, a phase transfer catalyst and a basic compound. (2) characterized by reacting with
(Chemical formula 2) [Chemical formula 2] (In the formula, R, R ₁ and R ₂ each independently represent a hydrogen atom or a lower alkyl group.) A method for producing an allyl bromide. 2. Water is added in an amount of 0.1 to allyl chlorides.
The method according to claim 1, which is used in the range of 30% by weight. 3. The method according to claim 1, wherein the basic compound used in the reaction is an alkali metal or alkaline earth metal carbonate, bicarbonate, phosphate, hydrogen phosphate or a tertiary amine. 4. The amount of the basic compound used in the reaction is 0.1% by weight to 20% by weight based on the allyl chlorides.
The method according to claim 1, characterized in that