JPH11139996A - Production of bromine compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject high-purity compound in a high yield without causing a side reaction, by carrying out the reaction between an aliphatic unsaturated compound and bromine in an inert solvent and removing a reaction heat out of the system by using the evaporation heat of the solvent or bromine. SOLUTION: A compound of formula I (Ar<1> and Ar<2> are each a 5-6C aromatic hydrocarbon or a 5-12C saturated alicyclic hydrocarbon; Y is a 1-6C saturated hydrocarbon, a ketone or the like; R<1> and R<2> are each an aliphatic unsaturated group-containing 2-11C hydrocarbon) is reacted with bromine in the presence of an inert solvent (preferably methylene chloride or the like) while removing the substantial amount of the reaction heat out of the system by the vaporization heat of the solvent or bromine to give the objective compound of formula II (R<3> and R<4> are each a group obtained by saturating the unsaturated group of R<1> or R<2> , respectively). 2,2-Bis (3,5-dibromo-4-allyloxy)phenyl}propane is preferable as the compound of formula I.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a bromine compound by brominating a compound having an aliphatic unsaturated bond. More specifically, the present invention relates to a method for industrially advantageously producing a high-purity bromine compound from a compound having an aliphatic unsaturated bond.

[0002]

2. Description of the Related Art Generally, in the field of organic chemistry, a bromination reaction to an aliphatic unsaturated group is a reaction that is frequently employed when synthesizing a brominated derivative. Due to the intensity of the reaction, it is essential to remove the reaction heat from within the reaction system.For this reason, the operation of cooling the reaction system and adding bromine over time in a mild state is generally adopted. ing.

For example, Japanese Patent Publication No. 49-39655 discloses a method for producing β, γ dibromopropylbenzene, but at a low temperature such that no side reaction occurs when bromine is added. The reaction is described.

Japanese Patent Application Laid-Open No. 55-111429 discloses that diallyl ether obtained from 2,2-bis-{(4-hydroxy-3,5-dibromo) phenyl} propane and allyl chloride is aromatic. It is disclosed that the bromination is carried out in a halogenated hydrocarbon solvent, but it is described that such bromination is carried out at a temperature of 10 to 30 ° C, especially 15 to 25 ° C. A method of adding bromine under cooling at a temperature of about 20 ° C. is illustrated.

Japanese Patent Application Laid-Open No. 50-30853 relates to a method for recovering a solid.
The reaction of 5-dibromo-4-allyloxy) phenyl} propane with bromine specifically describes a method of dropping bromine at a temperature of 20 ° C. or lower.

In Japanese Patent Application Laid-Open No. 7-173092, as a method for obtaining a 2,3-dibromopropyl compound, specifically, 2,2-bis {(3,5-dibromo-4-
For the reaction of bromine with allyloxy) phenyl-propane or the like, a method in which bromine is added dropwise at a reaction temperature of 10 to 20 ° C. over 1 hour is described.

Further, in Japanese Patent Application Laid-Open No. 7-316087, as a specific example, a reaction with 2,2-bis {(3,5-dibromo-4-allyloxy) phenyl} propane in methylene chloride by using a cooling tube. 24 to 27 ° C
A method is disclosed in which bromine is dropped over 1 hour while controlling the temperature.

On the other hand, for example, Japanese Patent Publication No. 50-23693 discloses a specific example of bis {(3,5-dibromo-
In bromination of 4-allyloxy) phenyl disulfone, a method is disclosed in which such a compound is dissolved in methylene chloride and bromine is reacted with the compound at the boiling point of methylene chloride.

The bromination of bis {(3,5-dibromo-4-allyloxy) phenyl} sulfone is described in JP-A-3-271267 and JP-A-4-234.
As disclosed in JP-A-354-354, specifically, the former is a method in which bromine is dropped at 39 ° C. or 40 ° C. over 1 hour to a methylene chloride solution of the compound, and the latter is bromine at 35 to 39 ° C. For 1.5 hours. In each of these methods, the reaction is carried out in a vessel having a cooling pipe.

[0010] The methods described in these patent publications are all small-scale reactions at the laboratory level. In many cases, a flask is used as a reactor, and most of the reactions are performed by cooling the reactor itself. A method of removing heat is employed. Although these publications disclose conditions and means at a laboratory level, they are effective on an industrial scale to effectively remove a large amount of heat of reaction and to obtain a high-purity bromide with a high yield. No specific conditions or means are disclosed.

In order to carry out bromination, particularly polybromination, of a compound having an aliphatic unsaturated bond on an industrial scale, it is necessary to effectively remove large amounts of reaction heat.
Development of means and devices for that purpose is required. In addition, when the heat of reaction is not effectively removed, bromine must be gradually supplied, so that the reaction time is prolonged, resulting in a decrease in yield and a decrease in purity.

[0012]

In view of this situation, the present inventor has developed a method for producing a highly pure bromine compound by efficiently reacting a compound having an aliphatic unsaturated bond with bromine on an industrial scale. As a result of intensive studies for the purpose of providing, the bromine is reacted with a compound having an aliphatic unsaturated bond and bromine in the presence of a solvent inert to the reaction. Was removed outside the reaction system by the heat of vaporization of the solvent or bromine, thereby producing a high-purity bromine compound in a high yield without causing a side reaction, and arrived at the present invention.

[0013]

That is, according to the present invention, a bromine compound represented by the following formula (2) is obtained by reacting a compound having an aliphatic unsaturated bond represented by the following formula (1) with bromine. Wherein the reaction is carried out in the presence of a solvent inert to the reaction, and a substantial amount of heat of reaction is removed from the reaction system by the heat of vaporization of the solvent or bromine. Is provided.

[0014]

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(In the formula, Ar ¹ and Ar ² may be the same or different and represent an aromatic hydrocarbon group having 5 to 16 carbon atoms or a saturated alicyclic hydrocarbon group having 5 to 12 carbon atoms. The hydrogen group may be substituted by at least one halogen atom, and Y is a saturated hydrocarbon group having 1 to 6 carbon atoms, a sulfone group, a sulfide group, a ketone group, an alkylene oxide group having 2 to 6 carbon atoms or a single atom. Represents a bond, R
¹ and R ² may be the same or different and represent a C ^{2 to} C 11 hydrocarbon group having at least one aliphatic unsaturated group, and one of R ¹ and R ² is an unsaturated group May be added by a halogen atom. )

[0016]

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(Wherein Ar ¹ , Ar ² and Y have the same meanings as defined in the above formula (1). R ³ and R ⁴ each represent an unsaturated group in R ¹ and R ² in the above formula (1)) Means a group wherein the group is saturated by a bromine atom.)

The compound having an aliphatic unsaturated bond used in the method of the present invention is represented by the above formula (1). In the above formula (1), Ar ¹ and Ar ² may be the same or different and each have an aromatic hydrocarbon group having 5 to 16 carbon atoms, preferably 6 to 12 carbon atoms, or 5 to 12 carbon atoms, preferably 5 to 12 carbon atoms. It is a saturated alicyclic hydrocarbon group having 6 to 10 carbon atoms. It is industrially advantageous that Ar ¹ and Ar ² are the same and are aromatic hydrocarbon groups. Specific examples of Ar ¹ and Ar ² include 1,4-phenylene group, 1,4-methylphenylene group, 1,4-dimethylphenylene group, 2,6-
A naphthylene group and a 2,7-naphthylene group;
A 4-phenylene group is preferred.

In these Ar ¹ and Ar ² , the carbon atom forming the hydrocarbon may be substituted with a halogen atom. Particularly, for the purpose of producing a flame retardant, a halogen atom, especially a bromine atom Is preferably substituted.
The number of halogen atoms substituted for each of Ar ¹ and Ar ² is preferably 1 to 6, preferably 2 to 4, with respect to Ar ¹ (or Ar ² ).

In the above formula (1), Y is a group or a bond connecting Ar ¹ and Ar ² and has 1 to 6 carbon atoms.
Preferably a saturated hydrocarbon group having 1 to 3 carbon atoms; sulfone group (-SO ₂ -); sulfide groups (-S-); ketone group (-CO-); 2 to 6 carbon atoms, preferably 2 to carbon atoms 4
Or an alkylene oxide group of the formula: or a single bond.
Desirable Y is a methylene group, an isopropylidene group, a cyclohexylidene group, a sulfone group, a sulfide group, a ketone group or a single bond.

In the above formula (1), R ¹ and R ² may be the same or different and have 2 to 11 carbon atoms having at least one aliphatic unsaturated group, preferably 2 to 2 carbon atoms.
5 represents a hydrocarbon group, and any one of R ¹ and R ² may have a part of the unsaturated group added by a halogen atom, preferably a bromine atom. Specific examples of R ¹ and R ² are preferably a vinyl group, an allyl group and an isobutenyl group.

As the compound having an aliphatic unsaturated bond represented by the above formula (1) of the present invention, specifically, 2,2-
Bis {(3,5-dibromo-4-allyloxy) phenyl} propane, 2,2-bis} (3,5-dibromo-4
-Isobutenyloxy) phenyl {propane, bis {(3,5-dibromo-4-allyloxy) phenyl}
Methane, bis {(3,5-dibromo-4-isobutenyloxy) phenyl} methane, (3,3 ', 5,5'-tetrabromo-4,4'-diallyloxy) biphenyl,
(3,3 ', 5,5'-Tetrabromo-4,4'-divinyloxy) biphenyl, bis {(3,5-dibromo-
4-allyloxy) phenyl} sulfone and bis {(3,5-dibromo-4-isobutenyloxy) phenyl} sulfone, among which 2,2-bis} (3,5-dibromo-4- Allyloxy) phenyl {propane, 2,2-bis} (3,5-dibromo-4)
-Isobutenyloxy) phenyl {propane, bis {(3,5-dibromo-4-allyloxy) phenyl}
Methane, bis {(3,5-dibromo-4-isobutenyloxy) phenyl} methane, (3,3 ', 5,5'-tetrabromo-4,4'-diallyloxy) biphenyl and (3,3' , 5,5'-Tetrabromo-4,4'-
Divinyloxy) biphenyl is preferred,
2-bis {(3,5-dibromo-4-allyloxy) phenyl} propane, 2,2-bis {(3,5-dibromo-4-isobutenyloxy) phenyl} propane, bis {(3,5- Dibromo-4-allyloxy) phenyl
Methane and bis {(3,5-dibromo-4-isobutenyloxy) phenyl} methane are more preferred, and 2,2-bis {(3,5-dibromo-4-allyloxy) phenyl} propane is particularly preferred. You.

In the method of the present invention, the reaction between the compound having an aliphatic unsaturated bond represented by the above formula (1) and bromine is carried out in the presence of a solvent. Must be active. The solvent inert to the reaction means inert to bromine, the compound having an aliphatic unsaturated bond and the bromine compound represented by the formula (2) (hereinafter, inert to the reaction). The solvent is simply abbreviated as “solvent”). Such a solvent is preferably the higher the solubility in a compound having an aliphatic unsaturated bond,
It may be partially soluble. Further, it is preferable that the bromine compound produced by the bromination reaction of the compound having an aliphatic unsaturated bond substantially dissolves in the solvent.

The solvent in the method of the present invention is not only used as a mere solvent for uniformly conducting the reaction, but also preferably functions as a solvent for effectively removing the heat of reaction out of the reaction system. Have. So the solvent is
Those having a normal pressure boiling point of 0 to 100 ° C, preferably 20 to 90 ° C, are advantageous. Especially 2
Those having a range of 0 to 60 ° C are desirable.

Examples of the solvent include halogenated hydrocarbons such as methylene chloride, chloroform, 1,2-dichloroethane, 1,1-dichloroethane, bromoethane, butyl chloride and chloropropane; diethyl ether, ethyl isopropyl ether, tetrahydrofuran, dioxane and the like. Examples include ether hydrocarbon compounds, aromatic hydrocarbon compounds such as benzene, carbon disulfide, pentane, and the like. Also, bromine can be used as a solvent.

Of these solvents, halogenated hydrocarbons are preferred, and methylene chloride and chloroform are particularly preferred as solvents. These solvents are used alone or in combination of two or more. These halogenated hydrocarbons can also be used as a mixed solvent with dioxane.

These solvents are used in an amount of 2 to 10 per one unsaturated group in the compound represented by the formula (1).
An amount corresponding to the number of 00 solvent molecules, preferably 2.5
It is used in an amount corresponding to the number of ~ 800 solvent molecules. In the reaction of the present invention, since it is a preferable embodiment to remove a substantial amount of the reaction heat out of the reaction system by the heat of vaporization of the solvent, the solvent is more preferably in an amount corresponding to the number of 3 to 700 solvent molecules. It is particularly advantageous to use them in an amount corresponding to the number of solvent molecules from 4 to 600.

The method of the present invention is characterized in that the heat of reaction is discharged by the heat of vaporization of the solvent or bromine, so that the amount of the solvent or bromine in the reaction system is at least an amount that can provide the heat of vaporization corresponding to the heat of reaction. However, since bromine participates in the reaction, it is reasonable and advantageous to remove the heat of reaction preferably by the heat of vaporization with a solvent.

In the reaction of the present invention, as the physicochemical background, heat of reaction of bromine to an aliphatic unsaturated bond,
It can be analyzed by the heat balance with the heat of vaporization of the solvent.
For example, in the addition reaction of Br ₂ to -CH = CH _2, the total binding energy is determined as follows.

The binding energy of C = C is 145 Kca
1 / mol and that of CH is 98.8 Kcal
/ Mol, there are three bonds. Since the binding energy value of Br-Br is 46.1 Kcal / mol, the sum of all is 145+ (98.8 × 3) + 46.1 = 48.
It becomes 7.5 Kcal / mol.

On the other hand, considering the product containing bromine after the reaction, the bond energy of C—Br in —CHBr—CH ₂ Br is 65.9 Kcal / mol,
There are two of these bonds, and CH is the same as the starting material (9
8.8 × 3) At Kcal / mol, the binding bond energy of C—C is 83.1 Kcal / mol, so the total is 511.3 Kcal / mol, and the difference between these two values, 23.8 Kcal / mol, is Pure heat of reaction (both are based on Chemical Handbook, edited by The Chemical Society of Japan, Vol. 122)
See page 5.)

The heat of vaporization of the solvent described so far is as follows:
Generally, it is 7 to 8 Kcal / mol (see Chemical Handbook, Vol. 2, pp. 271 of the Chemical Society of Japan), and the solvent is defined as the amount of the solvent contributing to the removal of the heat of reaction, based on the amount of the compound having an aliphatic unsaturated bond. The content is preferably within the above range per unsaturated group in the compound.

The amount of bromine used in the method of the present invention may be a sufficient molar ratio to the compound having an aliphatic unsaturated bond in order to obtain a desired bromine compound. The amount of bromine is preferably in the amount corresponding to the number of 1 to 5 bromine molecules, more preferably in the amount corresponding to the number of 1.1 to 3 bromine molecules per unsaturated group in the compound having Is used.

In the method of the present invention, bromine is used by itself or as a bromine solution. As the solvent used in the bromine solution, the same solvent as described above is used, and in that case, the concentration of bromine is 10 to 90% by weight.
Is preferable.

In the method of the present invention, as a specific means, a compound having an aliphatic unsaturated bond or a solution thereof is mixed with bromine or a bromine solution, so that the compound having an aliphatic unsaturated bond and bromine are mixed. Let react. At the time of this bromination reaction, it is an essential condition that a substantial amount of the heat of the bromination reaction is removed by a solvent or the heat of vaporization of bromine. The substantial amount of the heat of reaction means at least 80%, preferably at least 85% of the theoretical calorific value generated by the desired bromination reaction.

The reaction temperature in the bromination reaction of the present invention is as follows:
As described above, a substantial amount of the heat of reaction for bromination may be any temperature at which the heat is removed by the heat of vaporization of bromine or the solvent, and such a bromination reaction is not limited to normal pressure, and may be performed under pressure or under reduced pressure. It can be carried out. The reaction temperature is preferably at least 0 ° C, more preferably at least 5 ° C. Further, when the boiling point of the solvent used is lower than the boiling point of bromine, the reaction temperature can be increased by applying pressure, and when the boiling point of the solvent used is higher than the boiling point of bromine, the reaction is performed by reducing the pressure. The temperature can be lowered. Thus, the reaction temperature in the bromination reaction of the present invention can be controlled by the operating pressure in relation to the type (boiling point) of the solvent used and the amount of bromine. Usually, the reaction temperature is in the range from 0 to 60 ° C, preferably in the range from 5 to 55 ° C, particularly preferably 10 to 55 ° C.
A range of ５０50 ° C. is advantageous.

In the method of the present invention, during the bromination reaction, a substantial amount of the heat of the bromination reaction is removed by the heat of vaporization of the solvent or bromine, but the vaporized vapor is placed at the top of the reactor. Liquefied by cooling with a condenser
A method of returning to the reaction system again, that is, a method of refluxing, is preferably used because of easy operation.

By removing a substantial amount of the heat of reaction for bromination with a solvent or the heat of vaporization of bromine, the resulting bromine compound becomes highly pure. Simply reacting a compound having an aliphatic unsaturated bond with bromine at a high temperature easily generates by-products and lowers the purity as compared with a reaction at a low temperature, but the method of the present invention requires a high purity. Can be obtained. This is considered to be because the compound having an aliphatic unsaturated bond and bromine are uniformly dispersed in the solution due to the stirring effect when the solvent or bromine is vaporized, and side reactions are less likely to occur.

In the method of the present invention, for example, as a method of mixing a solution in which a compound having an aliphatic unsaturated bond is dissolved in a solvent and bromine or a bromine solution, bromine or a bromine solution is prepared by mixing a bromine or a bromine solution with an aliphatic unsaturated bond. A method of adding and mixing a compound solution having an aliphatic unsaturated bond to a solution of a compound, and conversely, a method of adding and mixing a solution of a compound having an aliphatic unsaturated bond to bromine or a bromine solution, or Any method of simultaneously adding the solution to the reactor and mixing the solution can be adopted.

In the method of the present invention, the reaction between the compound having an aliphatic unsaturated bond and bromine is carried out in the presence of a solvent, and a substantial amount of the heat of reaction is removed from the reaction system by the heat of vaporization of the solvent or bromine. Therefore, it is desirable to employ conditions and means for effectively discharging a large amount of reaction heat as a vapor of the solvent or bromine outside the reaction system by vaporization of the solvent or bromine. These conditions and means will be described below in detail and in detail. However, the reaction components and the solvent are uniformly contacted, and the solvent or bromine is effectively vaporized, and the reaction heat is discharged out of the system. Is desirably performed smoothly so that the reaction can be completed early and a bromine compound having excellent purity can be obtained. For this reason, adoption of means for sufficiently mixing the reaction mixture in the reaction system gives more preferable results.

Thus, the selection of the above-mentioned solvent and its ratio,
It is industrially advantageous that the ratio of bromine and the reaction temperature are set within the above ranges. Further, the presence of water in the reaction system affects the purity and quality of the bromine compound.

In the reaction of the present invention, impurities present in the reaction solution are important factors for efficiently performing the bromination reaction of the present invention and for obtaining a bromine compound of high yield and high purity. . In particular, water present in the reaction solution reacts with bromine to form an active intermediate, and the active intermediate reacts with the aliphatic unsaturated group in a competitive reaction, so that the It is necessary to pay close attention to the presence of water contained in the compound having an unsaturated bond, bromine and the solvent, and basically, coexistence of water should be avoided. Therefore, the concentration of water is preferably in a range corresponding to the number of water molecules of 0.1 or less per one unsaturated group of the compound having an aliphatic unsaturated bond.
It is more preferably in the range corresponding to the number of 0005 to 0.1 water molecules, and even more preferably in the range corresponding to the number of 0.0005 to 0.05 water molecules. As the concentration of water increases, the resulting bromine compounds tend to be low-purity, easily adhere to each other, and become solids that lack storage stability. The water content is measured by the Karl Fischer method.

The process of the present invention may be carried out in a batch system, as long as the substantial amount of the heat of reaction is discharged out of the reaction system as the heat of vaporization of the solvent or bromine, preferably the majority of the heat of reaction is discharged as the heat of vaporization of the solvent. Either a semi-batch system or a continuous system can be used. The batch system and the continuous system will be described below for the sake of simplicity, but partial changes and modifications are permissible as long as the essence of the present invention is not impaired. In particular, the semi-batch mode is easily adopted by the combination known per se from the description of the batch mode and the continuous mode. In the following description, a compound having an aliphatic unsaturated bond may be simply referred to as an “unsaturated compound”.

(I) Batch system: In the batch system, an unsaturated compound, bromine and a solvent are charged into a reactor in an arbitrary order, the reaction and heat of reaction are removed in the reactor, and the reaction is substantially completed until the reaction is completed. In this method, the reaction mixture is not taken out. This batch system is classified into the following Ia to Id.

Method (Ia); This method (Ia)
In this method, the unsaturated compound, bromine, and the solvent are separately supplied to the reactor separately or simultaneously as a mixture of any combination. In this method (Ia), it is desirable to supply a predetermined ratio of the unsaturated compound, bromine and the solvent to the reactor at substantially the same ratio, and the solvent may be added as a solution of the unsaturated compound, and It may be added as a solution. When the solvent is added as a solution of an unsaturated compound and / or a solution of bromine, the solvent may be supplementarily added alone, or a part of the solvent may be charged in the reactor in advance.

As described above, in the reaction of the present invention, it is desirable that the unsaturated compound, bromine and the solvent come into contact with each other uniformly and effectively. Therefore, a reactor equipped with a stirrer is used. Further, a reactor in which the solvent and bromine vaporized by the reaction heat are refluxed into the reaction system by a condenser provided at the top of the reactor is advantageous. The reactor equipped with the stirrer and the condenser is advantageously employed in any of the following systems.

Method (Ib): This method (Ib)
In this method, bromine or a bromine solution is supplied to a reactor filled with an unsaturated compound or a solution thereof. In this method (Ib), the solvent is preferably added as a solution of the unsaturated compound, bromine or both, but it is also possible to supplement a part of the solvent alone.

In this method (Ib), the bromination reaction can be carried out in a short time, and the productivity is improved, so that it is industrially extremely excellent. Since the bromination reaction itself is almost completed in several tens of seconds, it is usually sufficient that the time from the start of the bromination reaction to the end of the reaction is within several minutes.

In this method (Ib), the method of adding bromine or a bromine solution to a solution of an unsaturated compound in a reactor will be described more specifically. That is, the bromine or the bromine solution has a rate of adding bromine of 0.4 mmol / sec or more, preferably 0.5 mmol / sec or more, more preferably 1 mmol / mol of the unsaturated compound.
/ Sec or more, particularly preferably 1.5 mmol / sec or more, and 1000 mmol / sec or less, preferably 30 mmol / sec or less.
0 mmol / sec or less, more preferably 100 mmol / sec.
A method is used in which the addition is carried out at a rate of not more than second, more preferably at most 50 mmol / sec, particularly preferably at most 20 mmol / sec. If the addition rate of bromine or the bromine solution is too slow, productivity may decrease, and if the addition rate is too fast, the reaction may not be controllable.

The product of the rate of addition of bromine (mmol / sec) and the concentration (mol / L) of a solution of the unsaturated compound in a solvent is preferably 0.7 or more per mole of the unsaturated compound. 0.7 to 200, more preferably 0.7 to 1
00 is adopted as a more preferable condition. If the value of the product is smaller than the above value, the concentration of the unsaturated compound solution will be remarkably reduced, and the production efficiency will be easily lowered.

Method (Ic): This method (Ic)
In this method, an unsaturated compound and bromine are separately supplied into a reactor filled with a solvent in advance. This method (I
In -c), the unsaturated compound is supplied as a solution in a solvent. Bromine can also be supplied as a solution. In this manner, the proportions of unsaturated compound, bromine and solvent are not substantially different from the ranges described above.

Method (Id): This method (Id)
In this method, an unsaturated compound or a solution thereof is supplied to a reactor filled with bromine or a solution of bromine. In this mode (Id), the solvent is preferably added as a solution of bromine, unsaturated compound or both, but it is also possible to supplement a part of the solvent alone.

In this method (Id), the bromination reaction can be performed in a short time, and the productivity is improved, so that it is industrially extremely excellent. Since the bromination reaction itself is almost completed in several tens of seconds, it is usually sufficient that the time from the start of the bromination reaction to the end of the reaction is within several minutes.

In this method (Id), a method of adding a solution of an unsaturated compound to bromine or a bromine solution in a reactor will be described. The rate at which the compound is added is preferably from 0.4 to 1000 mmol / sec, more preferably from 0.4 to 300 mmol / sec, and even more preferably from 0.4 to 300 mmol / sec.
The method of adding so that it may become 5-100 mmol / sec is employ | adopted.

(II) Continuous system: As a continuous system, a compound having an aliphatic unsaturated bond represented by the above formula (1) is reacted with bromine to form a bromine compound represented by the above formula (2). In the production method, the compound represented by the formula (1), bromine and a solvent inert to the reaction are continuously supplied to a reactor separately or as a mixture of any combination. To the compound represented by the formula (1), an amount of bromine corresponding to the number of bromine molecules of 1 to 5 per unsaturated group in the compound is supplied, and the reaction heat is reduced in the reactor. The reaction was performed while removing the actual mass by the heat of vaporization of the solvent or bromine, and the reaction mixture was removed from the reactor,
Next, a method of recovering the bromine compound represented by the formula (2) from the reaction mixture can be desirably employed.

In the continuous system, the compound represented by the formula (1), bromine and the solvent are supplied separately or continuously as a mixture of any combination. At this time, the compound represented by the formula (1) (unsaturated compound)
And bromine react rapidly when they come in contact with each other,
It should be avoided to mix the two in advance and feed them to the reactor.

In carrying out the continuous method, the method of supplying the unsaturated compound, bromine and the solvent to the respective reactors is classified into the following (i) to (iii). (I) The solution of the unsaturated compound and the bromine are separately supplied. (Ii) separately providing a solution of the unsaturated compound and a solution of bromine. (Iii) The unsaturated compound, bromine and the solvent are separately supplied.

The desired bromine compound can be separated and recovered from the reaction mixture obtained by the above-mentioned bromination reaction by a method known per se. However, unreacted bromine remains in the reaction mixture. Therefore, the method of treating residual bromine with a reducing agent, converting bromine into hydrobromic acid once, and then adding an alkaline neutralizing agent is usually used. Has been adopted.

As the reducing agent used in such a treatment,
It is a reducing agent used in a normal reduction reaction, specifically, sodium bisulfite, sodium dithionite,
Sodium sulfite, oxalic acid, hydrogen sulfide, sodium nitrite, potassium nitrite, hydroxylamine sulfate, tin, stannous oxide, hydrazine, and the like; sodium bisulfite, sodium dithionite, sodium sulfite, oxalic acid, Sodium nitrate is preferably used. These reducing agents can also be used as an aqueous solution. These reducing agents are used alone or in combination of two or more.

Examples of the alkaline neutralizing agent include alkali metal hydroxides, alkali metal carbonates, alkaline earth metal hydroxides and alkaline earth metal carbonates. ,Sodium hydroxide,
Potassium hydroxide, sodium carbonate, potassium carbonate, calcium hydroxide, calcium carbonate, and the like are preferable, and sodium hydroxide is particularly preferably used. These alkaline neutralizing agents are preferably used as an aqueous solution. These alkaline neutralizing agents are used alone or in combination of two or more.

From the reaction mixture treated in the manner described above,
The desired bromine compound is recovered by a method known per se, for example, by precipitation with a poor solvent.

Thus, according to the method of the present invention, the unsaturated compound represented by the above formula (2) is saturated by a bromine atom by the bromination reaction of the unsaturated compound represented by the formula (1). ) Is obtained as a highly pure bromine compound. Further, the obtained bromine compound can be identified by a usual analysis method, for example, analysis of ¹ H-NMR spectrum and IR spectrum.

The bromine compound obtained by the method of the present invention has a purity of 90% or more, preferably 92% or more, and particularly preferably 95% or more. Such a high-purity bromine compound is useful as a flame retardant for thermoplastic resins, and is particularly suitable as a flame retardant for ABS resins and styrene resins.

[0064]

The present invention will be described below in detail with reference to examples. In addition, the compound having an aliphatic unsaturated bond represented by the formula (1) in Examples is sometimes abbreviated as “raw material compound”. Further, the measurement of the purity, the bromine content, and the specific gravity were performed according to the following methods.

(1) Purity of bromine compound The purity of the bromine compound was measured by high performance liquid chromatography (SCL-6B, manufactured by Shimadzu Corporation).
The measurement was performed by a method of detecting the absorption in nm. The sum of the peak areas of the components obtained from the chromatography was defined as 100, and the ratio of the peak area of the bromine compound to the sum was determined.

(2) Bromine content The sample was heated with fuming nitric acid in a closed container to decompose the sample, and the generated hydrobromic acid was quantitatively analyzed by a method of titrating with silver nitrate (the Calius method). .

(3) Specific Gravity The specific gravity was measured at 20 ° C. using a glass specific gravity bottle.

Example 1 A 1 L glass reactor equipped with a stirrer, a condenser, a thermometer and a dropping funnel was placed
135 g (0.216 mol) of 2,2-bis {(3,5-dibromo-4-allyloxy) phenyl} propane
And 230 g of methylene chloride dehydrated with synthetic zeolite was added and dissolved (the specific gravity of this solution was 1.47, and the concentration calculated therefrom was 0.87 mol / L).
This solution was stirred and 72.7 g of bromine (0.455 mol) was refluxed at a temperature of 39-41 ° C. with methylene chloride.
1) was dropped from the dropping funnel in 8 minutes (the rate of addition of bromine was 4.4 mmol / sec per 1 mol of the starting compound).
After completion of the dropwise addition, the reaction solution was continuously stirred at a temperature of 39 to 41 ° C. for 30 minutes while refluxing methylene chloride, thereby completing the bromine addition reaction.

Next, excess bromine in the reaction solution was reduced with 50 g of a 15% by weight aqueous sodium hydrogen sulfite solution, and the generated hydrogen bromide was neutralized with a 25% by weight aqueous sodium hydroxide solution. Thereafter, a methylene chloride layer was separated from this solution, and about 90% of the methylene chloride was evaporated and removed from the methylene chloride layer, and 500 mL of methanol was added thereto.
The reaction product was precipitated by addition, and the precipitate was filtered to remove a massive solid. This massive solid is crushed in a mortar,
The product was dried under reduced pressure at 5 mmHg for 3 hours at 19 ° C.
g was obtained (yield 97.2%).

When the obtained product was analyzed by ¹ H-NMR, the signal derived from —CHBr— was found to be 4.51 to 4.53 ppm, and the signal —CH ₂ Br was found to be 3.94 to 4.09 ppm.
Originated signals were observed. Further, from FT-IR analysis, it was confirmed that -O-CH ₂ -absorption was observed and no allyl group absorption was observed. From the above analysis results, the product was found to be 2,2-bis {3,5-dibromo-4- (2,3-
It was confirmed to be dibromopropyloxy) phenyl @ propane. This bromine compound has a purity of 96.8%,
Melting point 110 ° C., bromine content 67.5% (theoretical 67.8%)
%)Met.

Example 2 In a 1 L glass reaction vessel used in Example 1, 2,2-bis {(3,5-dibromo-4-isobutenyloxy) phenyl} propane 14 was added.
0.8 g (0.216 mol), 163 g of methylene chloride dehydrated with synthetic zeolite and 1,4-dioxane 70
g of the mixed solvent was added and dissolved (specific gravity of the solution was 1.3).
5). While stirring this solution and refluxing the mixed solvent,
79.5 g (0.497 mol) of bromine was added dropwise from the dropping funnel in 9 minutes (the addition rate of bromine was 1.09 mmol / sec with respect to 1 mol of the starting compound). After the completion of the dropwise addition, the reaction solution was continuously stirred for 30 minutes while refluxing the mixed solvent to terminate the bromine addition reaction.

The obtained reaction solution was subjected to the same operation as in Example 1 to obtain 203.3 g of a white solid product (yield: 96.8%). The product obtained in the same manner as in Example 1 ¹ H
As a result of analyzing using -NMR and FT-IR, the product was found to be 2,2-bis {3,5-dibromo-4- (2,3
-Dibromo-2-methylpropyloxy) phenyl} propane. This bromine compound has a purity of 96.5% and a bromine content of 65.3% (theoretical value: 65.8%).
%)Met.

[Example 3] In Example 2, 2,2-
Bis (3,5-dibromo-4-isobutenyloxy)
Bis {(3,5-dibromo-4-allyloxy) phenyl} methane 128.7 g instead of phenyl {propane
(0.216 mol) (specific gravity of solution 1.3)
4) Instead of dropping 79.5 g of bromine in 9 minutes, 8.3
Bromination was carried out in the same manner as in Example 2 except that the solution was dropped in minutes, to obtain 191.4 g of a product (yield: 96.7%).

[0074] Example 1 and similarly obtained product ¹ H-
As a result of analysis using NMR and FT-IR, it was confirmed that the product was bis {3,5-dibromo-4- (2,3-dibromo-propyloxy) phenyl} methane. This bromine compound had a purity of 96.7% and a bromine content of 69.5% (theoretical value: 69.8%).

[Example 4] In Example 1, 2,2-
Instead of 135 g of bis {(3,5-dibromo-4-allyloxy) phenyl} propane, bis {(3,5-dibromo-4-isobutenyloxy) phenyl} methane 13
Except that 4.8 g (0.216 mol) was used (specific gravity of the solution was 1.47), bromination was carried out in the same manner as in Example 1 to obtain 197.6 g of a product (yield 96.9%). .

[0076] Example 1 and similarly obtained product ¹ H-
As a result of analysis using NMR and FT-IR, it was confirmed that the product was bis {3,5-dibromo-4- (2,3-dibromo-2-methylpropyloxy) phenyl} methane. This bromine compound has a purity of 96.8.
% And a bromine content of 67.7% (theoretical value: 67.8%).

[Example 5] In Example 1, 2,2-
Instead of 135 g of bis {(3,5-dibromo-4-allyloxy) phenyl} propane, (3,3 ', 5,5'
-Tetrabromo-4,4'-diallyloxy) biphenyl was brominated in the same manner as in Example 1 except that 125.7 g (0.216 mol) of the solution (specific gravity of the solution was 1.47), and the product 186 was obtained. 2.6 g was obtained (yield 95.8).
%).

The product obtained in the same manner as in Example 1 was treated with ¹ H-
As a result of analysis using NMR and FT-IR, the product was identified as {3,3 ′, 5,5′-tetrabromo-4,4′-
(2,3-Dibromo-propyloxy)} biphenyl was confirmed. The compound has a purity of 95.7%,
The bromine content was 70.8% (theoretical 70.9%).

Example 6 In Example 1, 230 g of methylene chloride was replaced with 86 g (specific gravity of the solution was 1.42).
Bromination was carried out in the same manner as in Example 1 except that 72.7 g of bromine was changed to 75 g (0.469 mol), and the product 1 was obtained.
99.5 g were obtained (yield 97.7%).

The product obtained in the same manner as in Example 1 was treated with ¹ H-
As a result of analysis using NMR and FT-IR, the product was found to be 2,2-bis {3,5-dibromo-4- (2,3-
It was confirmed to be dibromopropyloxy) phenyl @ propane. This bromine compound had a purity of 96.7%.

Example 7 In Example 1, 2,2-
Bis {(3,5-dibromo-4-allyloxy) phenyl} propane was replaced with 135 g of 268 g (0.430 g).
mol), 230 g of methylene chloride was replaced with 493 g (specific gravity of the solution was 1.42), and 80 g of 72.7 g of bromine were added.
(0.500 mol), except that bromination was carried out in the same manner as in Example 1 to obtain 392.8 g of a product (yield 96.9%).

The product obtained in the same manner as in Example 1 was treated with ¹ H-
As a result of analysis using NMR and FT-IR, the product was found to be 2,2-bis {3,5-dibromo-4- (2,3-
It was confirmed to be dibromopropyloxy) phenyl @ propane. This bromine compound had a purity of 96.8%.

[Embodiment 8] In Embodiment 1, 2,2-
Bis {(3,5-dibromo-4-allyloxy) phenyl} propane was replaced with 135 g by 162 g (0.260
mol), 230 g of methylene chloride was replaced by 234 g (specific gravity of the solution was 1.47), and 72.7 g of bromine was 95 g.
(0.594 mol), and brominated in the same manner as in Example 1 to obtain 234.7 g of a product (yield: 95.8%).

[0084] Example 1 and similarly obtained product ¹ H-
As a result of analysis using NMR and FT-IR, the product was found to be 2,2-bis {3,5-dibromo-4- (2,3-
It was confirmed to be dibromopropyloxy) phenyl @ propane. This bromine compound had a purity of 96.6%.

[Embodiment 9] In Embodiment 1, 2,2-
Bis (3,5-dibromo-4-isobutenyloxy)
Instead of 140.8 g of phenylpropane, 148 g (0.220 mol) of bis {(3,5-dibromo-4-isobutenyloxy) phenyl} sulfone was used, and 230 g of methylene chloride was replaced with 121 g (specific gravity of the solution). 1.41), 72.7 g of bromine (72.0 g, 0.4
Bromination was carried out in the same manner as in Example 1 except that the amount was changed to 51 mol) to obtain 206.9 g of a product (yield: 94.8).
%).

The product obtained in the same manner as in Example 1 was treated with ¹ H-
As a result of analysis using NMR and FT-IR, it was confirmed that the product was bis {3,5-dibromo-4- (2,3-dibromo-2-methylpropyloxy)} sulfone. The compound had a purity of 95.3% and a bromine content of 64.1% (theoretical 64.4%).

[Comparative Example 1] In Example 1, bromine was dropped over 120 minutes, and the reaction temperature was 20 ° C while cooling.
Except that the bromination reaction is performed without refluxing methylene chloride (the rate of addition of bromine is
0.29 mmol / sec), and performed in the same manner as in Example 1, to obtain 2,2-bis {3,5-dibromo-
The yield of 4- (2,3-dibromopropyloxy) phenyl} propane was 96.5%, but its purity was 8%.
It was as low as 9.7%.

Comparative Example 2 The procedure of Example 1 was repeated, except that bromine was dropped over 120 minutes to carry out the bromination reaction (the rate of addition of bromine was 0.29 m
mol / sec) in the same manner as in Example 1. At this time, the solution temperature at the start of the dropping of bromine was 20 ° C., but as the bromine was dropped, the solution temperature gradually increased due to the heat of reaction, and reached 37 ° C. at the end of the dropping. The reaction vessel was not cooled and methylene chloride did not reflux. The obtained 2,2-bis {3,5-dibromo-4-
The purity of (2,3-dibromopropyloxy) phenyl} propane was as low as 63.0%.

The results of Examples 1 to 9 and Comparative Example 1 are shown in Tables 1 and 2. Here, the starting compounds (1) to (6) in the table are: (1) 2,2-bis {(3,5-dibromo-4-allyloxy) phenyl} propane (2) 2,2-bis} ( 3,5-dibromo-4-isobutenyloxy) phenyl {propane (3) bis} (3,5-dibromo-4-allyloxy)
Phenyl {methane (4) bis {(3,5-dibromo-4-isobutenyloxy) phenyl} methane (5) (3,3 ′, 5,5′-tetrabromo-4,4 ′
-Diallyloxy) biphenyl (6) represents bis {(3,5-dibromo-4-isobutenyloxy) phenyl} sulfone, and the solvents (A) and (B) have the following composition. (A) methylene chloride (B) methylene chloride / 1,4-dioxane = 70/30
(Weight ratio) The addition rate is the rate of addition of bromine to 1 mol of the starting compound.

[0090]

[Table 1]

[0091]

[Table 2]

[0092]

According to the method of the present invention, a high-purity bromine compound can be obtained by efficiently reacting a compound having an aliphatic unsaturated bond with bromine. It is suitably used as a flame retardant for resins, and its industrial effect is exceptional.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07C 49/84 C07C 49/84 C 315/04 315/04 317/22 317/22 319/20 319/20 323/20 323/20 C09K 21 / 08 C09K 21/08 (72) Inventor Yasuhiro Shimizu 1-2-2, Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Teijin Chemicals Co., Ltd. (72) Haruhisa Hoshimi 1-2-2, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Kasei Co., Ltd.

Claims (6)

[Claims] 1. A method for producing a bromine compound represented by the following formula (2) by reacting a compound having an aliphatic unsaturated bond represented by the following formula (1) with bromine: A process for producing a bromine compound, which is carried out in the presence of an active solvent, and wherein a substantial amount of heat of reaction is removed outside the reaction system by the heat of vaporization of the solvent or bromine. Embedded image (In the formula, Ar ¹ and Ar ² may be the same or different, and have an aromatic hydrocarbon group having 5 to 16 carbon atoms or 5 carbon atoms.
To 12 saturated alicyclic hydrocarbon groups, which may be substituted with at least one halogen atom, and Y represents a saturated hydrocarbon group having 1 to 6 carbon atoms, a sulfone group, or a sulfide group. , A ketone group, an alkylene oxide group having 2 to 6 carbon atoms or a single bond, wherein R ¹ and R ² may be the same or different, and have 2 to 11 carbon atoms having at least one aliphatic unsaturated group. It represents a hydrogen group, and ^one of R ¹ and R ² may have a part of the unsaturated group added by a halogen atom. ) (In the formula, Ar ¹ , Ar ² and Y have the same meanings as defined in the above formula (1). R ³ and R ⁴ each represent a case where the unsaturated group in R ¹ and R ² in the above formula (1) is bromine. Means a group saturated by an atom.) 2. A solution in which a compound having an aliphatic unsaturated bond represented by the formula (1) is dissolved in a solvent inert to the reaction,
When bromine or bromine solution is added and reacted for bromination, the rate of adding bromine is 0.4 to 1000 mmol per 1 mol of the compound having an aliphatic unsaturated bond.
The method for producing a bromine compound according to claim 1, wherein bromine or a bromine solution is added at a rate of 1 / sec. 3. A rate of adding bromine (mmol / sec) to 1 mol of the compound having an aliphatic unsaturated bond represented by the formula (1) and inactivating the compound having the aliphatic unsaturated bond in the reaction. Concentration (mol /
The method for producing a bromine compound according to claim 2, wherein the product of L) and L) is 0.7 or more. 4. The solvent is added to the compound represented by the formula (1) in an amount of from 2 to 1000 per unsaturated group in the compound.
The method for producing a bromine compound according to claim 1, wherein the bromine compound is used in an amount corresponding to the number of solvent molecules. 5. The method for producing a bromine compound according to claim 1, wherein the compound having an aliphatic unsaturated bond is a compound represented by the following formula (3). Embedded image (In the formula, Ar ¹ and Ar ² may be the same or different, and have an aromatic hydrocarbon group having 5 to 16 carbon atoms or 5 carbon atoms.
Represents a saturated alicyclic hydrocarbon group of from 1 to 12, X represents a halogen atom, m and n represent an integer of from 1 to 6, and R ¹ , R ² and Y have the same meanings as defined in the above formula (1). I do. ) 6. The compound having an aliphatic unsaturated bond,
2,2-bis {(3,5-dibromo-4-allyloxy) phenyl} propane, 2,2-bis {(3,5-dibromo-4-isobutenyloxy) phenyl} propane, bis {(3 5-dibromo-4-allyloxy) phenyl {methane, bis {(3,5-dibromo-4-isobutenyloxy) phenyl} methane, (3,3 ′, 5,
5'-tetrabromo-4,4'-diallyloxy) biphenyl, (3,3 ', 5,5'-tetrabromo-4,
4'-divinyloxy) biphenyl, bis {(3,5-
The method for producing a bromine compound according to claim 1, which is one kind of compound selected from dibromo-4-allyloxy) phenyl} sulfone and bis {(3,5-dibromo-4-isobutenyloxy) phenyl} sulfone.