Hydrogen bromide addition agent and method for producing bromine compound using the same

Abstract

To provide a hydrogen bromide addition agent that can be produced safely on an industrial scale, is very stable against oxygen and light, and facilitates its handling and storage.SOLUTION: The present invention provides a bromine-containing complex composed of a polar solvent and hydrogen bromide, where the polar solvent is an amide-based aprotic polar solvent, and a hydrogen bromide addition agent including the same, a method for producing a bromine-containing complex and a method for producing a bromine-containing compound using the same.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a bromine-containing complex and a hydrogen bromide addition agent. More specifically, the present invention relates to a bromine-containing complex used as a hydrogen bromide addition agent, a method for producing a bromine compound using the same, and a hydrogen bromide addition agent containing the bromine-containing complex. [Background technology]

[0002] Brominated organic compounds are useful compounds that can be used in various reactions, including coupling reactions, as synthetic intermediates for pharmaceuticals and industrial chemicals. Many methods for the bromination of organic compounds have been known for a long time, and research and development into these methods is still ongoing.

[0003] Hydrogen bromide is commonly used as a hydrogen bromide addition agent. Hydrogen bromide is an uncolored, irritating gas that is highly corrosive and toxic, and requires special equipment and techniques for handling (see, for example, Non-Patent Document 1).

[0004] As for the form of hydrogen bromide, in addition to hydrogen bromide gas, hydrogen bromide solutions such as an aqueous hydrogen bromide solution (hydrobromic acid) and a hydrogen bromide acetic acid solution are commercially available.

[0005] Hydrobromic acid is a colorless liquid, but it slowly oxidizes during storage, releasing bromine and gradually turning yellow. This coloring is accelerated by exposure to light, so it must be stored in a brown glass bottle. In addition, since hydrogen bromide is released into the air over time in all of the above hydrogen bromide solutions, it is necessary to quantitatively measure the hydrogen bromide concentration in the solution before quantitative use. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] "Organic Synthesis of Bromine and Iodine Compounds" by Manac Co., Ltd., Maruzen Publishing, published January 30, 2017 Summary of the Invention [Problem to be solved by the invention]

[0007] In view of these conventional techniques, the present inventors have an object of the present invention to provide a bromine-containing complex and a hydrogen bromide addition agent containing the same that can be safely produced on an industrial scale, are stable to oxygen and light, and are easy to handle and store. Another object of the present invention is to provide a method for producing a bromine compound using the hydrogen bromide addition agent containing the bromine-containing complex. [Means for solving the problem]

[0008] As a result of extensive investigations, the present inventors have found that a bromine-containing complex composed of a polar solvent and hydrogen bromide, in which the polar solvent is an amide-based aprotic polar solvent, can be safely produced on an industrial scale, is highly stable against oxygen and light, and is easy to handle and store.

[0009] They further discovered that this bromine-containing complex is an excellent agent for adding hydrogen bromide to olefin compounds, and that its use in the reaction can be carried out very safely and easily, which led to the completion of the present invention.

[0010] That is, the present invention relates to the following gist.

[0011] [1] A bromine-containing complex comprising a polar solvent and hydrogen bromide, the polar solvent being at least one selected from amide-based aprotic polar solvents. [2] The bromine-containing complex according to [1], wherein the polar solvent is at least one selected from the group consisting of urea-based aprotic polar solvents. [3] The polar solvent is bis(1,3-dimethyl-2-imidazolidinone); The following general formula (1) [ka] The bromine-containing complex according to item [1], [4] The polar solvent is N,N'-dimethylpropylene urea, represented by the following general formula (2): [ka] The bromine-containing complex according to item [1], [5] The following general formula (3) R 1 -CH=CH-R 2 (3) (In formula (3), R 1 is a substituted or unsubstituted aryl group, R 2 represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a hydrogen atom. 1 and R 2 may be bonded to each other to form a cyclic compound; The method is characterized in that the bromine-containing complex according to any one of items [1] to [4] is reacted with The following general formula (4) [ka] (In formula (4), R 1 and R 2 is the same as general formula (3). [6] A hydrogen bromide addition agent comprising the bromine-containing complex according to any one of items [1] to [4]. Effect of the Invention

[0012] The present invention makes it possible to provide a hydrogen bromide addition agent which can be produced safely on an industrial scale, is stable to oxygen and light, and is easy to handle and store. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a diagram showing the state in Example 2 in which the solid DMI·HBr obtained in Example 1 is placed in a glass container in air. [Diagram 2]FIG. 2 shows the state of the solid DMI·HBr obtained in Example 1 after a storage test in air at room temperature for 2 weeks in a glass container covered with a lid in air in Example 2. [Diagram 3] FIG. 2 is a diagram showing a state in which a commercially available 47% aqueous hydrogen bromide solution is placed in a glass container in the air in Comparative Example 1. [Figure 4] FIG. 2 shows the state of a commercially available 47% aqueous hydrogen bromide solution in a glass container in air, with a lid on, after a storage test in air at room temperature for two weeks in Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present invention will be described in detail below.

[0015] The bromine-containing complex of the present invention is a bromine-containing complex composed of an amide-based aprotic polar solvent and hydrogen bromide.

[0016] Examples of amide-based aprotic polar solvents include N,N-dimethylacetamide, N,N-diethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N'-dimethylpropyleneurea, 1,3-dimethyl-2-imidazolidinone (N,N'-dimethylethyleneurea), tetramethylurea, and tetraethylurea. Among these, at least one selected from the group consisting of urea-based aprotic polar solvents such as N,N'-dimethylpropyleneurea, 1,3-dimethyl-2-imidazolidinone, tetramethylurea, and tetraethylurea is preferred.

[0017] As specific preferred examples of the bromine-containing complex, the following compounds can be mentioned, however, the present invention is not limited to these exemplary compounds.

[0018] Examples of the bromine-containing complex according to the present invention include N,N-dimethylacetamide / hydrogen bromide complex, N,N-diethylacetamide / hydrogen bromide complex, N-methyl-2-pyrrolidone / hydrogen bromide complex, N-ethyl-2-pyrrolidone / hydrogen bromide complex, N,N'-dimethylpropyleneurea / hydrogen bromide complex, 1,3-dimethyl-2-imidazolidinone / hydrogen bromide complex, tetramethylurea / hydrogen bromide complex, and tetraethylurea / hydrogen bromide complex.

[0019] Among these, the following formula (1) [ka] or the following formula (2): [ka] The N,N'-dimethylpropyleneurea·hydrogen bromide complex represented by the following formula is more preferably used because of its stability, ease of handling, and ease of production method.

[0020] The bromine-containing complex represented by the above formula (1) can be safely and easily produced by adding an amide-based aprotic polar solvent to a solvent and then adding a hydrogen bromide (HBr) solution to the solvent, as shown in the following scheme (5). [ka]

[0021] In carrying out the reaction of the above scheme (5), the order of adding reactants may be appropriately determined, taking into consideration the reactivity of the hydrogen bromide solution, the properties of the liquid, etc., for example, adding the hydrogen bromide solution after the amide-based aprotic polar solvent and the solvent into a reaction vessel.

[0022] The bromine-containing complex represented by the above formula (2) can be safely and easily produced by adding an amide-based aprotic polar solvent to a solvent and then adding a hydrogen bromide (HBr) solution to the solvent, as shown in the following scheme (6). [ka]

[0023] In carrying out the reaction of the above scheme (6), the order of adding reactants may be appropriately determined, taking into consideration the reactivity of the hydrogen bromide solution, the properties of the liquid, etc., for example, adding the hydrogen bromide solution after the amide-based aprotic polar solvent and the solvent into a reaction vessel.

[0024] The solvent for the hydrogen bromide (HBr) solution that can be used in the production of the bromine-containing complex of the present invention is not particularly limited as long as it is a solvent that does not react with hydrogen bromide or an amide-based aprotic polar solvent, and examples of the solvent include aliphatic ethers and cyclic ethers. More specifically, examples of the solvent include dimethyl ether, ethyl methyl ether, diethyl ether, diisopropyl ether, methyl tert-butyl ether, cyclopentyl methyl ether (CPME), tetrahydrofuran, methyl tetrahydrofuran, tetrahydropyran (THP), 1,4-dioxane, 1,3-dioxane, glyme, diglyme, triglyme, and tetraglyme.

[0025] In the production of the bromine-containing complex of the present invention, the amount of hydrogen bromide used in the production is 0.1 to 1.0 times, and preferably 0.2 to 0.8 times, in molar ratio, relative to the amount of the amide-based aprotic polar solvent.

[0026] In the production of the bromine-containing complex of the present invention, the reaction temperature is preferably from -40°C to 80°C, and more preferably from -20°C to 60°C.

[0027] In the production of the bromine-containing complex of the present invention, the reaction time varies depending on the type of hydrogen bromide solution and the reaction temperature, so is not particularly limited, but the reaction can usually be completed within a range of 30 minutes to 2 hours.

[0028] The bromine-containing complex obtained by the present invention can be used as a hydrogen bromide addition agent or the like in its crude form as is, but can also be purified by known extraction methods, distillation methods, recrystallization methods, or the like, so that the contents of the raw material solvent, raw material hydrogen bromide, and the like present as impurities can be reduced or made substantially free of them.

[0029] Thus, the hydrogen bromide addition agent of the present invention contains a bromine-containing complex represented by the above general formula (1) or formula (2), and in order to use the agent in various reactions as a hydrogen bromide addition agent, a solvent in which the bromine-containing complex is soluble, an oxygen scavenger or a desiccant when the agent is stored as a powdered solid, and other additives can be used within the range of not interfering with the reaction to obtain the target product.

[0030] Next, the method of using the bromine-containing complex of the present invention and the hydrogen bromide addition agent containing the same will be described.

[0031] For example, when an olefin compound is brominated using the above-mentioned bromine-containing complex, the following procedure can be mentioned.

[0032] That is, the following general formula (3) R 1 -CH=CH-R 2 (3) (In formula (3), R 1 is a substituted or unsubstituted aryl group, R 2 represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a hydrogen atom. 1 and R 2 and may be bonded to each other to form a cyclic compound. The following formula (1) [ka] or a compound represented by the following formula (2): [ka] and reacting a compound represented by the formula: The following general formula (4) [ka] (In formula (4), R 1 and R 2 is the same as general formula (3).

[0033] In the method of using the bromine-containing complex and the hydrogen bromide addition agent containing the same of the present invention, examples of olefin compounds that can be used in the reaction include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-bromostyrene, 3-bromostyrene, 4-bromostyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 2-iodostyrene, 3-iodostyrene, 4-iodostyrene, 2-fluorostyrene, 3-fluorostyrene, 4-fluorostyrene, 2-(trifluoromethyl)styrene, 3-(trifluoromethyl)styrene, and Styrene, 4-(trifluoromethyl)styrene, 2-methoxystyrene, 3-methoxystyrene, 4-methoxystyrene, 4-acetoxystyrene, 4-cyanostyrene, 4-tert-butylstyrene, 3-t-butoxystyrene, 4-t-butoxystyrene, 4-isobutylstyrene, 3-nitrostyrene, 4-(tert-butyldimethylsiloxy)styrene, 4-trimethylsilylstyrene, α-methylstyrene, β-methylstyrene, 4-isopropenyltoluene, 3,4-dichlorostyrene, 3,5-dibromostyrene, 2,3-di Fluorostyrene, 2,4-difluorostyrene, 2,5-difluorostyrene, 2,6-difluorostyrene, 3,4-difluorostyrene, 3-bromo-2-fluorostyrene, 2-chloro-5-(trifluoromethyl)styrene, 2-fluoro-3-(trifluoromethyl)styrene, 3,5-bis(trifluoromethyl)styrene, 2,5-dimethylstyrene, 3,4-dimethoxystyrene, 4-chloro-α-methylstyrene, 4-fluoro-β-nitrostyrene, 2,4,6-trimethylstyrene, 2,4-difluoro-3-(trifluoromethyl)styrene, styrenes such as 2,3,4,5,6-pentafluorostyrene, 4,4'-dimethyl-trans-stilbene, cis-stilbene, trans-stilbene, 4-methylstilbene, 2-methylstilbene, 4-cyano-trans-stilbene, trans-4-bromostilbene, 4,4'-dibromo-trans-stilbene, 4,4'-diiodo-trans-stilbene, 4-aminostilbene, 4-methoxy-trans-stilbene, 4,4'-dimethoxy-trans-stilbene, 3,3',4,Examples of olefin compounds of condensed unsaturated carbocyclic aryls such as stilbenes such as 5'-tetrahydroxy-trans-stilbene, benzocyclobutadiene, indene, 6-methyl-1H-indene, 7-methyl-1H-indene, 4,7-dimethyl-1H-indene, 4,6-dimethyl-1H-indene, 6-methoxy-1H-indene, 7-methoxy-1H-indene, 5-chloro-1H-indene, 6-chloro-1H-indene, 7-chloro-1H-indene, 5-fluoro-1H-indene, 1,2-dihydronaphthalene, 6-methoxy-1,2-dihydronaphthalene, 7-methoxy-1,2-dihydronaphthalene, and 1-benzosuberene can be mentioned. However, they are not limited to these.

[0034] In the method of using the bromine-containing complex and the hydrogen bromide addition agent containing the same of the present invention, the amount of the bromine-containing complex used is 0.5 to 2.0 times, preferably 0.7 to 1.5 times, in molar ratio to the olefin compound.

[0035] In the method of using the bromine-containing complex and the hydrogen bromide addition agent containing the same of the present invention, the reaction solvent is not particularly limited as long as it is a solvent that does not react with the reaction substrate, reaction reagent, or product, but preferred are acetonitrile, dichloromethane, chloroform, glyme, diglyme, dimethylformamide, benzene, toluene, hexane, diethyl ether, trifluoroethanol, hexafluoroisopropanol, and the like.

[0036] In the method of using the bromine-containing complex and the hydrogen bromide addition agent containing the same of the present invention, the reaction temperature may be −20° C. to 150° C., and preferably 0° C. to 100° C. Furthermore, during the reaction, a hydrogen bromide scavenger, a base, an acid catalyst, etc. may be added as long as they do not adversely affect the bromine-containing complex represented by the above general formula (1) and the reaction product.

[0037] In the method of using the bromine-containing complex and the hydrogen bromide addition agent containing the same of the present invention, the reaction time is not particularly limited, but the reaction can usually be completed within a range of 30 minutes to 10 hours.

[0038] The bromine compound produced by the reaction of the present invention can be easily extracted from the reaction mixture by known extraction, distillation, recrystallization, etc. In that case, if unreacted compound represented by the above general formula (1) is present, hydrogen bromide is generated, which may be captured with sodium bicarbonate, etc. EXAMPLES

[0039] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0040] The following instruments were used for the analysis: 1 H-NMR: Manufactured by JEOL Ltd., model JEOL-ECS-400 spectrometer 13 C-NMR: Manufactured by JEOL Ltd., model JEOL-ECS-400 spectrometer IR: JASCO Corporation, model FT / IR-4100 Elemental analysis: Carbon, hydrogen, nitrogen: Yanaco Analysis Industry Co., Ltd., Model MT-7 was used, and the measured values ​​were compared with the calculated values. Melting point: Yanaco Corporation Micro melting point measuring device MP-J3 The measurements were carried out as described above.

[0041] Example 1: Preparation of bis(1,3-dimethyl-2-imidazolidinone)·hydrogen bromide complex (hereinafter abbreviated as DMI·HBr) 5.45g (5.39mmol) of 8% by weight hydrogen bromide (hereafter abbreviated as HBr) / diglyme solution and 20ml of diethyl ether were placed in a 50ml eggplant flask, stirred to dissolve, and cooled on ice. 2.11g (18.5mmol) of 1,3-dimethyl-2-imidazolidinone (hereafter abbreviated as DMI) and 10ml of diethyl ether were added, and stirring was continued for 20 minutes while cooling on ice. After the reaction was completed, the precipitated solid was filtered using a glass filter, washed with diethyl ether, and dried in vacuum to obtain 0.69g of a pale orange solid (see Figure 1). Yield 77%.

[0042] The resulting product was analyzed, with the following results: Melting point: 68℃-71℃. IR: 3388, 1638cm- 1 1 H-NMR (CDCl3, TMS) δ 10.70-9.59 (1H, br), 3.66 (4H, s), 3.14 (6H, s) 13 C-NMR (CDCl3) δ 159.99, 46.65, 33.20 Elemental analysis:DMI・HBr・1.5H2O Calculated values: C: 27.04, H: 6.35, N: 12.61 Actual measurements: C: 27.38, H: 5.83, N: 12.75 As stated above, 1 H-NMR, 13 The solid was confirmed to be DMI·HBr by C-NMR and elemental analysis.

[0043] Example 2. Long-term storage of DMI·HBr The DMI·HBr crystals obtained in Example 1 were pale orange solids as shown in Figure 1 (note that Figure 1 is a black and white image). In Figure 1, the DMI·HBr crystals were placed in a glass container (with a polypropylene lid).

[0044] DMI·HBr was placed in a glass container, capped, and stored in air at room temperature for two weeks. After two weeks, no discoloration or loss of purity was observed in DMI·HBr, as shown in Figure 2 (note that Figure 2 is a black and white image). Also, as shown in Figure 2, no corrosion was observed in the glass container.

[0045] Example 3: Preparation of N,N'-dimethylpropylene urea·hydrogen bromide complex (hereinafter abbreviated as DMPU·HBr) 5.45g (5.39mmol) of 8% HBr / diglyme solution and 20ml of diethyl ether were placed in a 50ml eggplant flask, stirred to dissolve, and cooled on ice. 2.37g (18.5mmol) of N,N'-dimethylpropylene urea (hereinafter abbreviated as DMPU) and 10ml of diethyl ether were added, and stirring was continued for 20 minutes while cooling on ice. After the reaction was completed, the precipitated solid was filtered using a glass filter, washed with diethyl ether, and dried in vacuum to obtain 0.98g of a pale orange solid. Yield 87%.

[0046] The resulting product was analyzed, with the following results: Melting point: 65-66℃. IR: 3359, 1654cm- 1 1 H-NMR (CDCl3, TMS) δ 3.44 (4H, t, J =5.8 Hz), 3.27 (6H, s), 2.11 (2H, quint, J = 6.0 Hz) 13 C-NMR (CDCl3) δ 156.48, 48.12, 38.92, 20.51 Elemental analysis: DMPU・HBr・2.5H2O Actual measurements: C: 28.36, H: 7.14, N: 11.02 Calculated values: C: 28.51, H: 6.61, N: 11.07 As stated above, 1 H-NMR, 13 The solid was confirmed to be DMPU·HBr by C-NMR and elemental analysis.

[0047] Example 4 Synthesis of 1-(1-bromoethyl)-4-methylbenzene 0.22g (1.13mmol) of DMI·HBr complex, 3ml of chloroform, and 0.125g (1.06mmol) of 4-methylstyrene were placed in a 30ml eggplant flask and reacted at 50℃ for 2 hours. The solution was thoroughly diluted with diethyl ether and then washed with water three times. After confirming that the washing water was neutral, the organic layer was washed with brine and dried over sodium sulfate. After removing the desiccant, the solvent was distilled off under reduced pressure to obtain 0.215g of a pale yellow liquid. The product was purified by silica gel column chromatography, and the solvent was distilled off under reduced pressure to obtain 0.204g of a colorless liquid.

[0048] 1 As a result of H-NMR measurement, it was confirmed that 1-(1-bromoethyl)-4-methylbenzene was produced in a yield of 97%.

[0049] Example 5 Synthesis of 1-(1-bromoethyl)-4-chlorobenzene The reaction was carried out in the same manner as in Example 4, except that 4-methylstyrene was replaced with 4-chlorostyrene and the reaction time was changed to 4 hours. 1 As a result of H-NMR measurement, it was confirmed that 1-(1-bromoethyl)-4-chlorobenzene was produced in a yield of 63%.

[0050] Example 6 Synthesis of 1-(1-bromoethyl)-4-methoxybenzene The reaction was carried out in the same manner as in Example 3, except that 4-methylstyrene was replaced with 4-methoxystyrene, the reaction temperature was changed to room temperature, and the reaction time was changed to 2 hours. 1 As a result of H-NMR measurement, it was confirmed that 1-(1-bromoethyl)-4-methoxybenzene was produced in a yield of 57%.

[0051] Example 7 Synthesis of 2-bromoindane The reaction was carried out in the same manner as in Example 3, except that 4-methylstyrene was replaced with indene, the reaction temperature was changed to 50° C., and the reaction time was changed to 4 hours. 1 As a result of H-NMR measurement, it was confirmed that 2-bromoindan was produced in a yield of 43%.

[0052] Comparative Example 1: Long-term storage of 47% hydrogen bromide aqueous solution (hydrobromic acid) A 47% aqueous solution of hydrogen bromide, which is commercially available as a reagent, was placed in the same glass container (with a polypropylene lid) as in Example 1. The 47% aqueous solution of hydrogen bromide was a pale yellow solution (FIG. 3).

[0053] A 47% hydrogen bromide solution was placed in a glass container, covered, and stored in air at room temperature for two weeks. After two weeks, the 47% hydrogen bromide solution had turned deep yellow, as shown in Figure 4.

[0054] Comparative Example 2 Synthesis of 1-(1-bromoethyl)-4-methylbenzene The reaction was carried out in the same manner as in Example 4, except that the DMI·HBr complex was replaced with an aqueous hydrobromic acid solution.

[0055] 1 H-NMR measurement confirmed that 1-(1-bromoethyl)-4-methylbenzene was produced in a yield of 22%.

[0056] Comparative Example 3 Synthesis of 1-(1-bromoethyl)-4-methylbenzene The reaction was carried out in the same manner as in Example 4, except that the DMI·HBr complex was replaced with a hydrogen bromide / acetic acid solution.

[0057] 1 H-NMR measurement confirmed that 1-(1-bromoethyl)-4-methylbenzene was produced in a yield of 89%.

[0058] Comparative Example 4 Synthesis of 1-(1-bromoethyl)-4-chlorobenzene The reaction was carried out in the same manner as in Example 5, except that the DMI·HBr complex was replaced with an aqueous hydrobromic acid solution.

[0059] 1 H-NMR measurement confirmed that 1-(1-bromoethyl)-4-methylbenzene was produced in a yield of 10%.

[0060] Comparative Example 5 Synthesis of 1-(1-bromoethyl)-4-chlorobenzene The reaction was carried out in the same manner as in Example 5, except that the DMI·HBr complex was replaced with a hydrogen bromide / acetic acid solution.

[0061] 1 H-NMR measurement confirmed that 1-(1-bromoethyl)-4-methylbenzene was produced in a yield of 51%.

[0062] The above is summarized in Table 1.

[0063] [Table 1]

[0064] It can be seen from Table 1 that in the Examples, the hydrobromination reaction of all the substrates proceeded efficiently, that is, with a high reaction yield. Furthermore, from Example 4 and Comparative Examples 2 and 3, and from Example 5 and Comparative Examples 4 and 5, it can be seen that the reaction yield differs depending on the hydrogen bromide addition agent, and that the use of the bromine-containing complex of the present invention as the hydrogen bromide addition agent results in an excellent reaction yield.

[0065] From Example 2 and Comparative Example 1, it can be seen that the hydrogen bromide addition agent such as DMI·HBr according to the present invention is stable, does not corrode the storage container, and can maintain its excellent properties as a hydrogen bromide addition agent for a long period of time. [Industrial Applicability]

[0066] The hydrogen bromide addition agent of the present invention can be safely produced on an industrial scale, is highly stable to oxygen and light during storage, and is easy to handle and store.Furthermore, it is an excellent hydrogen bromide addition agent for olefin compounds, and its use in the reaction is extremely safe and easy to carry out, making it extremely useful.

Claims

1. A bromine-containing complex comprising a polar solvent and hydrogen bromide, the polar solvent being at least one selected from amide-based aprotic polar solvents.

2. 2. The bromine-containing complex according to claim 1, wherein the polar solvent is at least one selected from the group consisting of urea-based aprotic polar solvents.

3. The polar solvent is bis(1,3-dimethyl-2-imidazolidinone), represented by the following general formula (1): 【Chemistry 11】 The bromine-containing complex according to claim 1, represented by the formula:

4. The polar solvent is N,N'-dimethylpropylene urea, represented by the following general formula (2): 【Chemistry 12】 The bromine-containing complex according to claim 1, represented by the formula:

5. The following general formula (3) R １ -CH=CH-R ２ (3) (In formula (3), R １ is a substituted or unsubstituted aryl group, R ２ represents a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a hydrogen atom; or R １ and R ２ and may be bonded to each other to form a cyclic compound, The method comprises reacting the bromine-containing complex according to any one of claims 1 to 4 with The following general formula (4) 【Chemistry 13】 (In formula (4), R １ and R ２ is the same as general formula (3).

6. A hydrogen bromide addition agent comprising the bromine-containing complex according to any one of claims 1 to 4.

Images