A method of photocatalytic co-production of organic bromides and hydrogen gas

Abstract

The application discloses a method for photocatalytic co-production of organic bromide and hydrogen, which comprises the following steps: mixing a raw material containing a substrate with a photocatalyst MAPbBr3, a hydrobromic acid solution and an organic solvent to obtain a mixed system, and irradiating the mixed system to generate a photocatalytic reaction, so as to obtain the organic bromide and hydrogen, wherein the substrate is at least one selected from a fused ring compound, a substituted fused ring compound, a bridged ring aromatic compound, a substituted bridged ring aromatic compound or a substituted benzene ring; the substituent group is selected from a methyl group or a methoxy group; and the number of the substituent group is 1, 2 or 3. The mild bromination path can complete the bromination of aromatic organic matters, and can also be used for the later functionalization of natural substances and drugs with complex structures.

Description

Technical Field

[0001] This application relates to a method for photocatalytic co-production of organic bromides and hydrogen, belonging to the field of photocatalytic synthesis. Background Technology

[0002] Bromination is a crucial class of organic reactions in organic synthesis. Brominates have been widely used in various organic reactions that synthesize carbon-carbon and carbon-heterobonds, such as the Suzuki-Miyaura, Sonogashira, Heck, Stille, and Buchwald-Hartwig cross-coupling reactions. Brominated organic compounds are widely found in nature and the chemical industry, and have important applications in pharmaceuticals, pesticides, dyes, fragrances, plasticizers, and flame retardants, with particular significance in drug synthesis.

[0003] Traditional synthetic methods generally do not meet the requirements of green synthesis. As one of the most powerful brominating agents for aromatic and aliphatic substrates, liquid bromine (Br2) is chosen as the bromine source in most laboratory and industrial processes. However, liquid bromine is highly volatile, extremely toxic and corrosive, requiring careful handling during storage, transportation, and use. Furthermore, the reaction produces one molecule of HBr, reducing the atom economy to below 50%; the substrate's functional group tolerance and regioselectivity are poor, and the product is prone to over-halogenation, generating byproducts. To avoid the use of elemental halogens, milder brominating agents such as N-bromosuccinimide (NBS) have been explored as bromine sources, offering safe operation and no HBr production. However, the synthesis of NBS still requires elemental bromine, and its sensitivity to light and heat significantly limits its application. The high cost and organic waste generated also hinder the large-scale application of NBS.

[0004] Hydrobromic acid (HBr) is inexpensive, readily available, and easy to store and transport. It also exhibits high atom economy in bromination reactions, making it a relatively ideal brominating reagent. Other forms of bromide ions, such as metal salts KBr and NBr, can also serve as ideal brominating reagents. When bromide ions are chosen as the brominating reagent, an oxidizing agent needs to be added to the reaction system to activate the bromide ions so that they can react with the substrate to form a C-Br bond.

[0005] Using HBr as a brominating agent, reported oxidants include nitrates, nitrites, dimethyl sulfoxide, sulfates, high-valent iodine, hydrogen peroxide, and molecular oxygen. The presence of these oxidants may lead to poor tolerance of functional groups sensitive to oxidation conditions, thus narrowing the range of substrates that can be used. The potential explosiveness of these oxidants also significantly limits the effectiveness of these oxidative halogenations. Choosing a suitable oxidant is crucial. In 2015, Jiao Ning's research group reported an efficient and practical DMSO / HX(Br,I) oxidation system for the halogenation of aromatics and heteroaromatics. Its high atom economy, broad substrate range, and low cost make this strategy highly attractive for developing aryl bromides. The simple reaction conditions also facilitate the later functionalization of natural products. From a green perspective, oxygen is an ideal oxidizing agent, producing only water as a byproduct. However, oxygen has relatively weak oxidizing power; when using oxygen as an oxidant, the reaction system needs to be carried out under the action of a catalyst. Among these, C-H bond halogenation reactions catalyzed by transition metals (palladium, copper, rhodium, ruthenium, cobalt) have become a green and efficient method for introducing specific halogens into organic compounds. In 2012, Wang Meixiang's research group reported the halogenation reaction of aromatic nitrogen heterocycles involving Cu(ClO4)2. The reaction requires the participation of air and provides an efficient and practical synthetic route for constructing CX(F, Cl, Br, I).

[0006] As an emerging green synthetic method, photocatalysis is increasingly being used in organic synthesis. In 2011, Fukuzumi's research group selected Acr... + Using Mes as a photocatalyst, HBr as the bromine source, and O2 as the oxidant, the bromination of aromatics and thiophenes was achieved with high conversion and high selectivity. In 2018, The research group established a superior photocatalytic bromination method using sodium anthraquinone-2-sulfonate (SAS) as a photocatalyst and sodium bromide as a bromine source, exhibiting broader functional group compatibility with the substrates. In 2020, the Jiang Xuefeng research group reported that by using bromide ions as the bromine source, air as the oxidant, and 4-(2-phenyl-1-acetylene)benzonitrile as the photocatalyst, the range of applicable substrates could be extended to aromatic compounds containing amino groups. Compared to homogeneous catalysts, heterogeneous catalysts are insoluble and can be recovered and reused through simple filtration. In 2016, the Zhang research group reported the use of organic polymer (MOP) heterogeneous photocatalysts, using HBr as the bromine source and molecular oxygen as the oxidant, to convert electron-rich aromatic compounds to brominated organic compounds with high conversion rate and high selectivity under visible light irradiation. In 2019, the Savateeva research group modified polymeric carbon nitride to obtain a new photocatalyst, K-PHI. Under aerobic conditions and visible light irradiation, K-PHI significantly improved the conversion of Br₂ in water... -Photocatalytic oxidation using anions can convert a range of aromatic compounds into their halogenated derivatives in high yields and with high selectivity. In these studies, the reaction conditions are mild, and the only byproduct is H₂O, with no other toxic or harmful waste generated. Summary of the Invention

[0007] Photocatalysis, as a highly efficient, green, and promising method for organic synthesis, is an ideal approach for producing high-value-added organic compounds. A photocatalytic system coupling organic synthesis and hydrogen production further enhances the overall value of the reaction. Previous work by the applicant revealed that the organic-inorganic hybrid perovskite methylamine lead bromide (MAPbBr3), with strong visible light absorption, can exist stably in saturated HBr and decomposes HBr to produce H2 under visible light irradiation. We further used HBr as the bromine source and MAPbBr3 as the photocatalyst to efficiently complete the bromination reaction of aromatic compounds while retaining the advantage of hydrogen production. In an aqueous solution saturated with MAPbBr3, a dissolution-precipitation dynamic equilibrium was established between the precipitated form of MAPbBr3 and its dissolved state in HBr, with MAPbBr3 in a stable state. Pt (0.75wt%) / Ta2O5 and PEDOT:PSS acted as electron and hole transport channels, respectively, effectively promoting the separation of photogenerated electrons and holes. N,N-Dimethylformamide (DMF) effectively improves the solubility of organic substrates in the reaction system without compromising system stability, thus further promoting the reaction. Organic compounds with similar structures to DMF can also enhance reactivity, with N,N-diisobutylformamide (DBF) showing the best relative performance. Mechanistic studies indicate that the bromination reaction proceeds via electrophilic substitution; the Br2 generated in the reaction reacts with water to form the active brominated species HOBr, which is likely a key bromination intermediate.

[0008] According to one aspect of this application, a method for photocatalytic co-production of organic bromides and hydrogen is provided, comprising at least the following steps:

[0009] A mixture of a raw material containing the substrate, a photocatalyst MAPbBr3, a hydrobromic acid solution, and an organic solvent is irradiated with light to induce a photocatalytic reaction, yielding the organic bromide and hydrogen gas.

[0010] The substrate is selected from at least one of the following: bicyclic compounds, substituted bicyclic compounds, bridged aromatic compounds, substituted bridged aromatic compounds, or substituted benzene rings;

[0011] The substituents in the substituted bicyclic compound or the substituted bridged aromatic compound are selected from methyl or methoxy groups;

[0012] The number of substituents in the substituted bicyclic compound or the substituted bridged aromatic compound is 1, 2 or 3.

[0013] The ring in the said bicyclic compound, substituted bicyclic compound, bridged aromatic compound or substituted bridged aromatic compound is selected from at least one of three-membered ring, four-membered ring, five-membered ring, six-membered ring, three-membered heterocycle, four-membered heterocycle, five-membered heterocycle or six-membered heterocycle;

[0014] The heteroatom in the heterocycle is selected from oxygen, sulfur, or nitrogen atoms;

[0015] The heterocycle contains 1, 2, or 3 heteroatoms.

[0016] The number of rings in the said cyclic compound, substituted cyclic compound, bridged aromatic compound or substituted bridged aromatic compound is selected from 2, 3 or 4;

[0017] The substituents of the substituted bridged aromatic compound also include fluorine atoms, chlorine atoms, or iodine atoms;

[0018] Furthermore, the ring compound is selected from compounds having the structure shown in Formula 1;

[0019]

[0020] The bridged ring aromatic compound is selected from compounds having the structure shown in Formula 2;

[0021]

[0022] The substituted bridged aromatic compound is selected from compounds having the structures shown in Formulas 3 to 5.

[0023]

[0024] Preferably, the substituted benzene ring is selected from compounds having the structures shown in Formulas 6 to 16;

[0025]

[0026] The organic solvent is selected from at least one of compounds having the structure shown in Formula 17;

[0027]

[0028] Wherein, R1 is selected from hydrogen atoms or C1-C4 alkyl groups;

[0029] R2 is selected from C1 to C4 alkyl groups;

[0030] Furthermore, R1 is selected from hydrogen atom, methyl, ethyl or n-propyl;

[0031] R2 is selected from methyl, ethyl, n-propyl, n-butyl, or isobutyl.

[0032] The organic solvent is selected from N,N-dimethylformamide, N,N-diethylformamide, N,N-dipropylformamide, N,N-dibutylformamide, N,N-diisobutylformamide, N,N-dimethylacetamide, N,N-dimethylpropionamide or N,N-dimethylbutyramide;

[0033] The molar ratio of the substrate to the organic solvent is 1:0.1 to 2;

[0034] Furthermore, the molar ratio of the substrate to the organic solvent is 1:1.

[0035] The mixture contains a conductive polymer and additives;

[0036] The conductive polymer is selected from PEDOT:PSS, Spiro-OMeTAD, or reduced graphene oxide;

[0037] The additive is selected from platinum.

[0038] The platinum metal is loaded onto the surface of the carrier;

[0039] The carrier is selected from Ta2O5, TiO2, Cu2O, WO3, and ZnO.

[0040] The volume ratio of the conductive polymer to the molar ratio of the substrate is 1–6 mL / mmol; the upper limit is 6 mL / mmol, 5 mL / mmol, 4 mL / mmol, 3 mL / mmol, and 2 mL / mmol; the lower limit is 1 mL / mmol, 2 mL / mmol, 3 mL / mmol, 4 mL / mmol, and 5 mL / mmol.

[0041] The mass ratio of the adjuvant to the molar amount of the substrate is 50–300 mg / mmol; the upper limit is 300 mg / mmol, 250 mg / mmol, 200 mg / mmol, 150 mg / mmol, and 100 mg / mmol; the lower limit is 50 mg / mmol, 100 mg / mmol, 150 mg / mmol, 200 mg / mmol, and 250 mg / mmol.

[0042] The mass ratio of the catalyst to the molar amount of the substrate is 1–6 g / mmol; the upper limit is 6 g / mmol, 5 g / mmol, 4 g / mmol, 3 g / mmol, and 2 g / mmol; the lower limit is 1 g / mmol, 2 g / mmol, 3 g / mmol, 4 g / mmol, and 5 g / mmol.

[0043] The hydrobromic acid solution contains 40–48 wt% hydrobromic acid.

[0044] The volume ratio of the hydrobromic acid solution to the molar amount of the substrate is 40–200 ml / mmol; the upper limit is 200 ml / mmol, 150 ml / mmol, 100 ml / mmol, and 50 ml / mmol; the lower limit is 40 ml / mmol, 50 ml / mmol, 100 ml / mmol, and 150 ml / mmol.

[0045] The illumination is visible light illumination;

[0046] The intensity of the illumination is 0.1–0.6 W / cm². -2 The upper limit is 0.6W cm. -2 0.5W cm -2 0.4W cm -2 0.3Wcm -2 0.2W cm -2 The lower limit is 0.1 W cm. -2 0.2W cm -2 0.3W cm -2 0.4W cm -2 0.5W cm -2 ;

[0047] The duration of illumination is 6–72 hours; the upper limit is 72 hours, 60 hours, 48 ​​hours, 36 hours, 24 hours, and 12 hours; the lower limit is 6 hours, 12 hours, 24 hours, 36 hours, 48 ​​hours, and 60 hours.

[0048] The photocatalytic reaction is carried out in an inert gas atmosphere;

[0049] The inactive gas atmosphere is selected from at least one of nitrogen, helium, or argon.

[0050] The hydrobromic acid solution is a saturated hydrobromic acid solution of the photocatalyst MAPbBr3.

[0051] Because MAPbBr3 is water-soluble, it is dissolved in HBr to form a saturated solution. In the saturated solution, a dynamic equilibrium of dissolution-precipitation is formed between the undissolved MAPbBr3 and the MAPbBr3 dissolved in HBr. The catalyst MAPbBr3 is constantly renewed through ion exchange to maintain its dynamic stability.

[0052] The reaction uses a saturated aqueous HBr solution as the solvent, in which MAPbBr3 reaches a stable state. In the experiment, a catalytic amount of MAPbBr3 was first added to the saturated HBr solution, then heated to dissolve it, completing the ion exchange between the catalyst MAPbBr3, the MAPbBr3 in the saturated HBr, and HBr. Cooling then allowed MAPbBr3 to precipitate completely, facilitating its catalytic activity. This step helps MAPbBr3 better exert its catalytic activity.

[0053] Br participating in the reaction - It doesn't just come from HBr, because of the ion exchange state between MAPbBr3 and HBr, the Br in the product... - Derived from MAPbBr3 and HBr.

[0054] The resulting organic bromide and hydrogen gas have a molar ratio of 1:1.

[0055] This application provides a mild bromination pathway that can complete the bromination of aromatic organic compounds and can also be used for the later functionalization of structurally complex natural substances and drugs; at the same time, it produces hydrogen and is economically efficient. Detailed Implementation

[0056] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0057] Unless otherwise specified, the raw materials and catalysts used in the embodiments of this application were all purchased commercially.

[0058] The analysis method in the embodiments of this application is as follows:

[0059] The gas produced by the photocatalytic bromination reaction was detected by gas chromatography (GC) using an Agilent GC7890 instrument.

[0060] The instrument used for HNMR testing was a Bruker AVANCE III 400MHz spectrometer.

[0061] In the embodiments of this application, the conversion rate and selectivity are calculated as follows:

[0062] Conversion rate = (Amount of substrate reacted / Amount of original substrate) * 100%

[0063] Selectivity = Target product / Total product * 100%

[0064] The ratio of product (i.e., reacted substrate) to remaining substrate can be calculated from the integral values ​​of the characteristic peaks of the product and substrate in the HNMR spectrum.

[0065] Example 1

[0066] Preparation of photocatalyst MAPbBr3

[0067] A 0.36 mol / L tributyl phosphate / chloroform mixed solution was prepared and used to extract 40 wt% hydrobromic acid three to five times. The mixed solution changed from pale yellow to colorless, yielding the treated hydrobromic acid. This step removes trace amounts of Br3 present in the hydrobromic acid. - .

[0068] Add 3.6110 g (0.645 mol / L) of MABr and 11.8361 g (0.645 mol / L) of PbBr2 to a 100 ml round-bottom flask, followed by 50 ml of treated hydrobromic acid. The solution turns orange. React this orange solution in an oil bath at 80–100 °C for 1 hour, cool to room temperature, and allow it to stand for a period of time to obtain a saturated solution of MAPbBr3. After centrifugation, obtain an orange MAPbBr3 precipitate, which is then vacuum dried at 55 °C for 36 hours to obtain orange MAPbBr3 powder, i.e., the photocatalyst.

[0069] Preparation of the additive Pt-Ta2O5

[0070] In a glass reactor, 200 mg of Ta₂O₅ was dispersed in 60 mL of deionized water and 15 mL of anhydrous methanol solution, followed by the addition of H₂PtCl₆ solution (1.308 mg / mL, 1.147 mL) to achieve a Pt loading of 0.75 wt% (1.5 mg). The solution was ultrasonically mixed to ensure homogeneity. Under vacuum conditions, the reactor was irradiated with a 300 W xenon lamp from the top for 8 hours, maintaining a fixed light intensity of 160 mW cm⁻¹. -2 An infrared filter filled with water is placed above the reactor to filter out infrared absorption from the light source and prevent the reaction solution from heating up due to infrared light absorption. A condensation circulation device maintains the temperature of the entire reaction system at approximately 15°C. The reacted solution is centrifuged, washed three times with deionized water, and the resulting precipitate is vacuum-dried at 60°C for 12 hours to obtain a gray powder additive, Pt (0.75 wt%) / Ta₂O₅.

[0071] Photocatalytic bromination reaction

[0072] The photocatalytic reaction is carried out in a quartz reactor, the side of which is provided with an irradiation area of ​​3 cm². 2 The window.

[0073] A 0.36 mol / L tributyl phosphate / chloroform mixed solution was prepared and used to extract 40 wt% hydrobromic acid three to five times, causing the mixed solution to change from pale yellow to colorless. This yielded treated hydrobromic acid. An excess of the photocatalyst MAPbBr3 powder was added to the treated hydrobromic acid and stirred continuously until MAPbBr3 precipitated, thus obtaining a saturated hydrobromic acid solution containing the photocatalyst MAPbBr3. The photocatalyst MAPbBr3 remained stable.

[0074] MAPbBr3 photocatalyst powder (150 mg) and Pt (0.75 wt%) / Ta2O5 (7.5 mg) were added to the reactor, along with a saturated hydrobromic acid solution (5 mL) of MAPbBr3. The mixture was heated to 80 °C to completely dissolve the MAPbBr3 powder, then cooled to room temperature to allow all MAPbBr3 to precipitate. After cooling, PEDOT:PSS solution (200 μL), reaction substrate (1,2,4-trimethoxybenzene, 0.05 mmol, 7.6 μL), and organic solvent (N,N-diisobutylformamide, 0.05 mmol, 9.1 μL) were added. The reactor was evacuated and purged with argon gas; this step was repeated three times to remove all oxygen from the reactor. A 300 W xenon lamp was used as the light source for the photocatalytic reaction, with a filter ensuring the light wavelength was greater than 420 nm and the light intensity fixed at 160 mW cm⁻¹. -2 The reaction temperature is controlled within the room temperature range.

[0075] The gas produced by the photocatalytic bromination reaction was detected by gas chromatography (GC) using an Agilent GC7890 instrument.

[0076] An appropriate amount of ethyl acetate was added to the solution following the photocatalytic bromination reaction. After extraction, the organic matter transferred to the ethyl acetate, resulting in an upper ethyl acetate solution containing the organic matter. A suitable amount of saturated sodium bicarbonate (NaHCO3) solution was then added, followed by extraction. The remaining trace amounts of HBr reacted with the NaHCO3, again resulting in an upper ethyl acetate solution containing the organic matter. A suitable amount of saturated sodium chloride (NaCl) solution was then added for further washing, resulting in an upper ethyl acetate solution containing the organic matter. The ethyl acetate was removed by rotary evaporation, yielding a mixture of organic matter. This mixture was then further dried under vacuum using a double-row tube technique to remove any remaining ethyl acetate, resulting in a dried mixture of organic matter. Deuterated chloroform (CDCl3) was used as the solvent, and tetramethylsilane (TMS) was used as the standard. The mixture was analyzed by 1H NMR using a Bruker AVANCE III 400MHz spectrometer. Analyzing the substrate-to-product ratio in the 1H NMR spectroscopy allowed for a rough calculation of the reaction conversion and selectivity.

[0077] Experimental results: Within 6 hours, the raw material (1,2,4-trimethoxybenzene) can be completely converted into the product (1-bromo-2,4,5-trimethoxybenzene) with a selectivity greater than 99%, and hydrogen gas is produced in an equimolar proportion with the product.

[0078] Examples 2-15

[0079] The methods in Examples 2 to 15 are the same as those in Example 1.

[0080] The results of Examples 1 to 15 are detailed in Table 1.

[0081] Table 1 shows the results of Examples 1-15.

[0082]

[0083]

[0084] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for photocatalytic co-production of organic bromide and hydrogen, characterized by, at least comprising the following steps, a mixture containing a substrate, a photocatalyst MAPbBr3, a hydrobromic acid solution and an organic solvent is irradiated to produce the organic bromide and hydrogen gas through photocatalytic reaction; the substrate is selected from at least one of fused ring compounds, substituted fused ring compounds, bridged ring aromatic compounds, substituted bridged ring aromatic compounds, or substituted benzene rings; the ring in the fused ring compounds, substituted fused ring compounds, bridged ring aromatic compounds or substituted bridged ring aromatic compounds is selected from at least one of three-membered rings, four-membered rings, five-membered rings, six-membered rings, three-membered heterocyclic rings, four-membered heterocyclic rings, five-membered heterocyclic rings or six-membered heterocyclic rings; the heteroatom in the heterocyclic ring is selected from oxygen atoms, sulfur atoms or nitrogen atoms; the number of heteroatoms in the heterocyclic ring is 1, 2 or 3; the number of rings in the fused ring compounds, substituted fused ring compounds, bridged ring aromatic compounds or substituted bridged ring aromatic compounds is selected from 2, 3 or 4; the substituted benzene ring is a compound with a structure shown in formula 6 to formula 16; formula 6; formula 7; formula 8; formula 9; formula 10; formula 11; formula 12; formula 13; formula 14; formula 15; formula 16; the substituent in the substituted fused ring compound or substituted bridged ring aromatic compound is selected from methyl or methoxy; the number of substituents in the substituted fused ring compound or substituted bridged ring aromatic compound is 1, 2 or 3; the hydrobromic acid solution is a saturated hydrobromic acid solution of the photocatalyst MAPbBr3, and a dissolution-precipitation dynamic balance is established in the reaction system; the mixture further contains an additive, and a conductive polymer or redox graphene; the conductive polymer is selected from PEDOT:PSS or Spiro-OMeTAD; the additive is selected from metallic platinum; the organic solvent is selected from at least one of compounds with a structure shown in formula 17; formula 17; wherein R1 is selected from hydrogen atoms or C1-C4 alkyl groups; R2 is selected from C1-C4 alkyl groups.

2. The method of claim 1, wherein, the fused ring compound is selected from a compound with a structure shown in formula 1; formula 1; the bridged ring aromatic compound is selected from a compound with a structure shown in formula 2; formula 2; the substituted bridged ring aromatic compound is selected from a compound with a structure shown in formula 3 to formula 5; formula 3; formula 4; formula 5.

3. The method of claim 1, wherein R1 is selected from hydrogen atoms, methyl groups, ethyl groups or n-propyl groups; R2 is selected from methyl groups, ethyl groups, n-propyl groups, n-butyl groups or isobutyl groups.

4. The method of claim 1, wherein the organic solvent is selected from N,N-dimethylformamide, N,N-diethylformamide, N,N-dipropylformamide, N,N-dibutylformamide, N,N-diisobutylformamide, N,N-dimethylacetamide, N,N-dimethylpropionamide or N,N-dimethylbutyramide; the molar dosage ratio of the substrate to the organic solvent is 1:0.1-2.

5. The method of claim 4, wherein the molar dosage ratio of the substrate to the organic solvent is 1:

1.

6. The method of claim 1, wherein the metallic platinum is loaded on the surface of a carrier; The carrier is selected from Ta2O5, TiO2, Cu2O, WO3, and ZnO.

7. The method according to claim 4, characterized in that, The mass ratio of the adjuvant to the molar ratio of the substrate is 50~300 mg / mmol.

8. The method according to claim 1, characterized in that, The mass ratio of the photocatalyst MAPbBr3 to the molar ratio of the substrate is 1~6 g / mmol; The hydrobromic acid solution contains 40-48 wt% hydrobromic acid. The volume ratio of the hydrobromic acid solution to the molar amount of the substrate is 40~200 ml / mmol.

9. The method according to claim 1, characterized in that, The illumination is visible light illumination; The intensity of the light is 0.1-0.6 W cm 2 ; The illumination time is 6~72 hours; The photocatalytic reaction is carried out in an inert gas atmosphere; The inactive gas atmosphere is selected from at least one of nitrogen, helium, or argon.

10. The method according to claim 1, characterized in that, The resulting organic bromide and hydrogen gas have a molar ratio of 1:1.

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