Preparation method of trimethyl gallium

Abstract

The invention provides a preparation method of trimethyl gallium, and relates to the technical field of trimethyl gallium preparation. According to the preparation method, metal gallium and a halogen simple substance are placed in a solvent for a reaction, the metal gallium is in a liquid state at the reaction temperature, and in the reaction process, the metal gallium is continuously stirred into fine particles, so that the fine particles make contact with the halogen simple substance in the solvent for a reaction, and a gallium halide compound is generated and dissolved in the solvent; according to the method, the metal gallium and the halogen elementary substance are used as raw materials and react in the solvent to generate the gallium halide solution, so that the problems that the halogen elementary substance and the metal gallium are difficult to mix and the reaction is only performed on the metal surface are solved, and the reaction efficiency is improved; after the reaction is finished, separating the reaction mixture, and directly separating the metal gallium which is not completely reacted to obtain a pure gallium halide solution; the gallium halide solution is used as a reaction raw material for preparing trimethyl gallium, so that the problems of high cost and difficult storage caused by directly adopting a gallium halide reagent as a raw material are avoided, and the preparation cost of trimethyl gallium is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of trimethylgallium preparation, and in particular to a method for preparing trimethylgallium. Background Art

[0002] Trimethylgallium is one of the most widely used metal organic compounds and is widely used in the preparation of optoelectronic compound materials.

[0003] There are many methods for preparing trimethylgallium. The main methods are the alkyl aluminum method, the gallium-magnesium alloy halide method and the Grignard reagent method. Among them, the alkyl aluminum method and the Grignard reagent method both use gallium halide as the reaction raw material. The alkyl aluminum method uses trimethylaluminum and gallium halide to carry out alkyl exchange reaction to prepare trimethylgallium, and the Grignard reagent method uses gallium halide and Grignard reagent to react to prepare trimethylgallium. The price of anhydrous gallium halide reagents is expensive, which will greatly increase the cost of raw materials. In addition, the anhydrous gallium halide reagents will smoke immediately after opening and contact with air, are easily hydrolyzed, and are hygroscopic. After opening, there are very high requirements for the subsequent use and storage conditions of the reagents. The synthesis process of trimethylgallium requires anhydrous and oxygen-free reaction conditions. If the anhydrous gallium halide reagent absorbs moisture and hydrolyzes, on the one hand, the loss of the reagent will affect the product yield, and on the other hand, the presence of moisture may also cause the reaction to fail.

[0004] The traditional method for preparing trimethylgallium has problems such as high cost, many by-products, and high toxicity. Therefore, how to prepare trimethylgallium at low cost and high efficiency has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The present application provides a method for preparing trimethylgallium to solve the following technical problem: how to prepare trimethylgallium at low cost.

[0006] The present application provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0007] Placing metal gallium and halogen in a solvent for a first reaction to obtain a reaction mixture;

[0008] separating the reaction mixture to obtain a gallium halide solution;

[0009] Using the gallium halide solution to prepare trimethylgallium;

[0010] Wherein, the halogen element is bromine element or iodine element;

[0011] The parameters of the first reaction include at least one of the following: a reaction temperature of 50° C. to 120° C., and a reaction time of 0.5 h to 3 h.

[0012] Optionally, the molar ratio of the metallic gallium to the halogen element is greater than 1:1.5.

[0013] Optionally, the gallium halide solution is used to prepare trimethylgallium, specifically comprising:

[0014] A methylmagnesium halide solution is obtained;

[0015] adding the gallium halide solution to the methylmagnesium halide solution for a second reaction to obtain a solution containing a trimethylgallium complex;

[0016] The solution containing the trimethylgallium complex is subjected to a decomposition reaction to obtain trimethylgallium.

[0017] Optionally, the molar ratio of the gallium halide to the methyl magnesium halide is 1:(3-3.8).

[0018] Optionally, the step of obtaining the methyl magnesium halide solution specifically comprises:

[0019] mixing magnesium with a solvent to obtain a mixture;

[0020] subjecting the mixture to a third reaction with methyl halide to obtain a methyl magnesium halide solution;

[0021] Wherein, the temperature of the third reaction is 40°C to 80°C.

[0022] Optionally, the solvent is an organic ether.

[0023] Optionally, the solvent includes at least one of the following: isopentyl ether, dipentyl ether and methyl phenyl ether.

[0024] Optionally, the second reaction of the gallium halide solution and the methylmagnesium halide solution to obtain a solution containing a trimethylgallium complex specifically includes:

[0025] The gallium halide solution is added dropwise to the methylmagnesium halide solution, and after the addition is completed, a second reaction is performed under set conditions to obtain a solution containing a trimethylgallium complex;

[0026] The dripping time is 2h to 6h;

[0027] The set conditions are: the reaction temperature is 50° C. to 110° C., and the reaction time is 6 h to 10 h.

[0028] Optionally, subjecting the solution containing the trimethylgallium complex to a decomposition reaction to obtain trimethylgallium specifically comprises:

[0029] The solution containing the trimethylgallium complex is subjected to reduced pressure distillation to obtain the trimethylgallium complex;

[0030] The trimethylgallium complex is distilled at normal pressure to obtain trimethylgallium.

[0031] Optionally, the pressure of the reduced pressure distillation is 10 kPa to 20 kPa, and the temperature is 90° C. to 150° C.; and / or,

[0032] The receiving temperature of the product of the atmospheric distillation is 55°C to 60°C.

[0033] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0034] The embodiment of the present application provides a method for preparing trimethylgallium. The method is carried out under an inert atmosphere and comprises the following steps: placing metal gallium and a halogen element in a solvent for reaction to obtain a reaction mixture; the reaction temperature is 50° C. to 120° C., the reaction time is 0.5 h to 3 h, the metal gallium is in a liquid state at the reaction temperature, and during the reaction, the metal gallium is continuously stirred into fine particles so as to contact with the halogen element in the solvent to react and generate a gallium halide compound dissolved in the solvent; after the reaction is completed, the reaction mixture is separated, and the metal gallium that has not reacted completely can be directly separated to obtain a pure gallium halide solution; the gallium halide solution is used as a reaction raw material for preparing trimethylgallium, including a Grignard reagent method and an alkyl aluminum method, etc., to avoid the high cost and difficult storage problems of directly using a gallium halide reagent as a raw material; and considering the difficulty and cost of the reaction, the halogen element is a bromine element or an iodine element.

[0035] The method uses metal gallium and halogen as raw materials, and generates a gallium halide solution by reaction in a solvent, thereby avoiding the problem that the halogen and metal gallium are difficult to mix and the reaction only occurs on the metal surface, thereby improving the reaction efficiency and reducing the preparation cost of trimethylgallium. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0038] Figure 1 The figure is a schematic flow chart of a method for preparing trimethylgallium according to some embodiments of the present application. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0040] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a rigid limitation on the scope of the present application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within the range; for example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which applies regardless of the range; in addition, whenever a numerical range is indicated in this document, it is meant to include any cited numbers (fractions or integers) within the indicated range.

[0041] In this document, the terms including "including" and "including" mean "including but not limited to". Relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone; where A and B can be singular or plural. "At least one" means one or more, and "plurality" means two or more; "at least one", "at least one of the following" or similar expressions, refers to any combination of these items, including any combination of single or plural items; for example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple. "Parts" such as parts by weight and parts by mass indicate the proportional relationship between the components. In the proportional relationship involved in this article, the parameters that need to be described by proportion should be understood as the first term of the proportional formula in the order of description, and the proportional numbers should be understood as the second term of the proportional formula. For example, if the mass ratio of substance A, substance B and substance C is 1:2:3, then substance A, substance B and substance C should correspond to the proportional numbers in the proportional formula in the order of description, that is, the mass of substance A: the mass of substance B: the mass of substance C = 1:2:3.

[0042] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this article can be purchased from the market or prepared by existing methods.

[0043] Figure 1 A schematic diagram of a process for preparing trimethylgallium according to some embodiments of the present application;

[0044] like Figure 1 As shown, the present application embodiment provides a method for preparing trimethylgallium, the preparation method being carried out under an inert atmosphere, comprising:

[0045] S1, placing metal gallium and halogen in a solvent for a first reaction to obtain a reaction mixture;

[0046] S2, separating the reaction mixture to obtain a gallium halide solution;

[0047] S3, using the gallium halide solution to prepare trimethylgallium;

[0048] Wherein, the halogen element is bromine element or iodine element;

[0049] The reaction parameters include at least one of the following: the reaction temperature is 50° C. to 120° C., and the reaction time is 0.5 h to 3 h.

[0050] In the above embodiment, gallium metal and halogen element are used as reaction raw materials to generate gallium halide for preparing trimethylgallium, which avoids the high cost and difficult storage problems of directly using gallium halide reagent as raw material. In addition, the halogen element is dissolved in the solvent, and the gallium metal is in liquid state at the reaction temperature. During the reaction, the gallium metal is continuously stirred into fine particles, so that it is continuously contacted with the halogen element in the solvent to react, and a gallium halide compound is generated and dissolved in the solvent until one of the reactants reacts completely; after the reaction is completed, it is directly separated to obtain a gallium halide solution, and the subsequent steps can be directly carried out.

[0051] In the above embodiment, the temperature of the reaction of metal gallium and halogen is controlled to be 50°C to 120°C because within this temperature range, it is more conducive to the efficient and stable reaction of metal gallium and halogen. When the reaction temperature is lower than 50°C, the reaction rate is slow and the reaction time is long. Too high a reaction temperature is not conducive to the smooth control of the reaction. Considering that the solution needs to be cooled before being used in the synthesis reaction, the reaction temperature does not need to be too high. Exemplarily, the reaction temperature can be 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C or 120°C.

[0052] This method adopts a new path of reacting metallic gallium and halogen elements in a solvent to obtain a gallium halide solution, and then further preparing trimethylgallium. Compared with the traditional alkyl aluminum method and alloy method, this has lower cost and higher efficiency. By accurately controlling the temperature and time of the reaction, this method can reduce energy consumption and the generation of by-products while ensuring the reaction efficiency, thereby further reducing costs. Although the specific type of solvent is not explicitly mentioned in this application, according to the common knowledge of trimethylgallium preparation, the choice of solvent is crucial for the reaction efficiency and the purity of the product. In actual operation, it is preferred to use a solvent with good solubility for reactants and products, moderate boiling point, and easy recovery. Reacting under an inert atmosphere can avoid the interference of oxygen and moisture, and ensure the smooth progress of the reaction and the purity of the product.

[0053] As an optional embodiment, the molar ratio of the metallic gallium to the halogen element is greater than 1:1.5.

[0054] In the above embodiment, the molar ratio of the metal gallium to the halogen element is controlled to be greater than 1:1.5 because when the metal gallium is excessive, the halogen element in the solvent is ensured to react completely, which facilitates the rapid separation of the reaction mixture in the later stage. The color change of the solution during the reaction process can reflect whether the halogen element has reacted completely. For example, when iodine element reacts, it changes from brown-black to gray-green in isoamyl ether solvent, and changes from dark brown-black to colorless and transparent in ethanol solvent.

[0055] As an optional embodiment, the molar ratio of the metal gallium to the halogen element is (1.2-3):1.5.

[0056] In the above embodiment, the molar ratio of metallic gallium to halogen is controlled to be (1.2-3):1.5, which helps to increase the reaction rate of halogen during the reaction to generate more gallium halide, thereby improving the efficiency of subsequent reactions and the purity of the product.

[0057] As an optional implementation, the separation of the reaction mixture to obtain a gallium halide solution specifically includes: cooling the reaction mixture to below 40° C., separating the reaction mixture to obtain a gallium halide solution.

[0058] By cooling the reaction mixture to below 40°C, the activity of the reaction system can be effectively reduced, making the properties of unreacted raw materials, by-products, solvents and other substances more stable, which is conducive to subsequent separation operations. At the same time, cooling can also reduce the mutual solubility of the components in the reaction mixture, making it easier to separate gallium halide from the mixture. By cooling to below 40°C and then separating, the separation efficiency of gallium halide can be effectively improved, and the residue of unreacted raw materials and by-products can be reduced, thereby improving the efficiency of subsequent reactions and the purity of the product. The cooling operation is relatively simple and has low energy consumption, and will not bring additional burden to the entire preparation process. After cooling, the gallium halide solution can be separated from the reaction mixture by an appropriate separation method (such as filtration, centrifugation, distillation, etc.). The specific separation method can be selected according to the composition and properties of the reaction mixture. The optimization of this step provides more stable and controllable process conditions for the entire preparation process, which is conducive to the realization of industrial production.

[0059] As an optional embodiment, the gallium halide solution is used to prepare trimethylgallium, specifically comprising:

[0060] S31, obtaining a methylmagnesium halide solution;

[0061] S32, adding the gallium halide solution to the methylmagnesium halide solution to carry out a second reaction to obtain a solution containing a trimethylgallium complex;

[0062] S33, subjecting the solution containing the trimethylgallium complex to a decomposition reaction to obtain trimethylgallium.

[0063] In the above embodiment, the second reaction is carried out using a Grignard reagent method and a homemade gallium halide solution, and the process is highly safe, and specifically includes:

[0064] S31: Obtaining a methylmagnesium halide solution, this step generally involves mixing magnesium with a solvent (such as an organic ether), and then reacting with a methyl halide under appropriate conditions to generate a methylmagnesium halide solution. Methylmagnesium halide is an active intermediate for subsequent reactions and is essential for the generation of trimethylgallium.

[0065] S32: Adding the gallium halide solution to the methylmagnesium halide solution for a second reaction, in which the gallium halide solution is slowly added to the methylmagnesium halide solution, and the two react at an appropriate temperature and pressure to generate a solution containing a trimethylgallium complex. The key to this step is to control the reaction conditions (such as temperature, pressure, reaction time, etc.) and the molar ratio of gallium halide to methylmagnesium halide to ensure efficient reaction and stability of the product.

[0066] S33: subjecting the solution containing the trimethylgallium complex to a decomposition reaction. After obtaining the solution containing the trimethylgallium complex, the trimethylgallium complex therein needs to be converted into free trimethylgallium through a decomposition reaction. This step generally involves operations such as vacuum distillation and / or atmospheric distillation to remove the solvent and other impurities in the complex to obtain high-purity trimethylgallium.

[0067] As an optional implementation, the molar ratio of the gallium halide to the methylmagnesium halide is 1:(3-3.8).

[0068] In the above embodiment, the reasons for controlling the molar ratio of the gallium halide to the methyl magnesium halide to be 1:(3-3.8) include:

[0069] Reaction efficiency: Within this molar ratio range, the reaction of gallium halide and methylmagnesium halide can proceed more fully, avoiding the problem of incomplete reaction or impure product caused by excess or insufficient raw materials. The appropriate molar ratio helps to optimize the reaction conditions, such as temperature, pressure and reaction time, thereby increasing the reaction rate and product yield.

[0070] Product purity: By precisely controlling the molar ratio of gallium halide to methylmagnesium halide, the formation of by-products can be reduced, thereby improving the purity of the final product. High-purity trimethylgallium is essential for its application in the semiconductor industry, organic synthesis and other fields.

[0071] Cost control: A reasonable molar ratio helps reduce the waste of raw materials, thereby reducing production costs. At the same time, high-purity products also mean higher product value, which helps to improve economic benefits.

[0072] Exemplarily, the molar ratio of the gallium halide to the methylmagnesium halide is 1:3, 1:3.1, 1:3.2, 1:3.3, 1:3.4, 1:3.5, 1:3.6, 1:3.7 or 1:3.8.

[0073] As an optional embodiment, the step of obtaining the methyl magnesium halide solution specifically comprises:

[0074] S311, mixing magnesium with a solvent to obtain a mixture;

[0075] S312, subjecting the methyl halide to a third reaction with the mixture to obtain a methyl magnesium halide solution;

[0076] Wherein, the reaction temperature is 40°C to 80°C.

[0077] In the above embodiment, the reason for controlling the reaction temperature to be 40°C to 80°C is that within this temperature range, the reaction rate is moderate, which can ensure the smooth progress of the reaction without causing side reactions. If the reaction temperature is lower than 40°C, the reaction rate is slow; if the reaction temperature is higher than 80°C, other side reactions may occur. Exemplarily, the reaction temperature may be 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C.

[0078] As an optional embodiment, the methyl halide is subjected to a third reaction with the mixture, specifically comprising: adding the methyl halide dropwise to the mixture for 1 hour to 3 hours, and continuing the reaction for 2 hours to 5 hours after the addition is completed.

[0079] The reason for controlling the time of dripping to be 1h to 3h is to ensure that methyl iodide can react evenly with the mixture to avoid side reactions caused by excessive local concentration. Exemplarily, the time of dripping can be 1h, 1.5h, 2h, 2.5h or 3h. After the dripping is completed, the reaction is continued for 2h to 5h to ensure that the reaction is complete. Exemplarily, the reaction can be continued for 2h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h after the dripping is complete.

[0080] As an optional embodiment, the solvent is an organic ether.

[0081] In the above embodiment, organic ethers are selected as solvents because metal ether solvents can dissolve alkyl halides and halogen elements, which is conducive to the contact between reactants and the progress of the reaction; magnesium metal is insoluble in the solvent, and the magnesium powder, magnesium particles or magnesium bars used in the Grignard reaction react with the alkyl halides in the solvent to generate methyl magnesium halide, and the unreacted magnesium is a solid that can be directly separated; secondly, the lone pair electrons of the oxygen atoms in the ether solvent can coordinate with the magnesium ions to form stable solvated magnesium ions, which helps to improve the stability of the Grignard reagent. Finally, since the solvents are the same, the generated gallium halide solution can directly undergo subsequent reactions, which helps to ensure the continuity of the preparation process.

[0082] As an optional embodiment, the solvent includes at least one of the following: isopentyl ether, dipentyl ether and methyl phenyl ether.

[0083] In the above embodiment, the reason for selecting isoamyl ether, diamyl ether or methyl phenyl ether as the solvent is that they have a higher boiling point, better thermal stability, can be applied to higher reaction temperatures, and are not easy to decompose; at the same time, they reduce solvent evaporation during the reaction and maintain the stability of the reaction system.

[0084] As an optional embodiment, the gallium halide solution and the methylmagnesium halide solution are subjected to a second reaction to obtain a solution containing a trimethylgallium complex, specifically comprising:

[0085] The gallium halide solution is added dropwise to the methylmagnesium halide solution, and after the addition is completed, a second reaction is performed under set conditions to obtain a solution containing a trimethylgallium complex;

[0086] The dripping time is 2h to 6h;

[0087] The set conditions are: the reaction temperature is 50° C. to 110° C., and the reaction time is 6 h to 10 h.

[0088] In the above embodiment, the gallium halide solution is added dropwise to the methyl magnesium halide solution, and the dropping time is controlled to be 2h to 6h in order to avoid the side reaction caused by the excessively high local concentration of the gallium halide solution, and to ensure that the gallium halide solution and the methyl magnesium halide solution are evenly mixed. The reason for controlling the reaction temperature to be 50°C to 110°C is that when the temperature is lower than 50°C, the reaction rate is too slow, and when the temperature is higher than 110°C, the temperature is too high, causing the side reaction. Exemplarily, the reaction temperature can be 50°C, 60°C, 70°C, 80°C, 90°C, 100°C or 110°C; the reaction time can be 6°C, 6.5°C, 7°C, 7.6°C, 8°C, 8.5°C, 9°C, 9.5°C or 10°C.

[0089] As an optional embodiment, subjecting the solution containing the trimethylgallium complex to a decomposition reaction to obtain trimethylgallium specifically comprises:

[0090] S331, distilling the solution containing the trimethylgallium complex under reduced pressure to obtain the trimethylgallium complex;

[0091] S332, subjecting the trimethylgallium complex to atmospheric distillation to obtain trimethylgallium.

[0092] In the above embodiment, the solution containing the trimethylgallium complex is firstly subjected to reduced pressure distillation. The boiling point of the complex is lower than that of the pure solvent. Therefore, during distillation, the head is low-boiling impurities and the middle fraction is the complex. The middle fraction is collected to obtain the trimethylgallium complex. Then, the trimethylgallium complex is decomposed by atmospheric distillation to obtain trimethylgallium.

[0093] As an optional embodiment, the pressure of the reduced pressure distillation is 10 kPa to 20 kPa, and the temperature is 90° C. to 150° C.

[0094] In the above embodiment, the pressure of the vacuum distillation is controlled to be 10kPa-20kPa and the temperature is 90°C-150°C because the selected organic ether solvents have high boiling points under normal pressure. By properly reducing the pressure and controlling the temperature, efficient separation of the trimethylgallium complex is achieved. Too low a pressure during the vacuum distillation process will lead to too low a boiling point, causing some low-boiling impurities to be distilled out, which will have an adverse effect on the distillation effect. At the same time, too low a boiling point also requires higher condensation conditions. When the pressure is high, the difference in evaporation temperature between components with different boiling points will decrease, resulting in a decrease in separation efficiency, and higher temperatures and longer distillation times are required to achieve the desired separation effect. Exemplarily, the pressure of the reduced pressure distillation is 10 kPa, 11 kPa, 12 kPa, 13 kPa, 14 kPa, 15 kPa, 16 kPa, 17 kPa, 18 kPa, 19 kPa or 20 kPa; the temperature is 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C or 150°C.

[0095] As an optional embodiment, during the atmospheric distillation, the temperature at which trimethylgallium is received is 55°C to 60°C, because the boiling point of trimethylgallium is 55.7°C.

[0096] The present application is further described below in conjunction with specific examples. The experimental methods in the following examples where specific conditions are not specified are usually measured in accordance with national standards / industry standards; if there are no corresponding national standards / industry standards, they are measured in accordance with common international standards, conventional conditions or conditions recommended by the manufacturer.

[0097] Example 1

[0098] This embodiment provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0099] (1) Obtaining a gallium iodide solution: Under an inert atmosphere, 45.0 g of metal gallium (excess) and 165.0 g of iodine are added to 200 g of isoamyl ether solvent, and reacted at 110° C. for 2 hours to prepare a gallium iodide solution. After the reaction is completed, stirring is continued until the temperature drops below 40° C., and the remaining metal gallium is separated from the gallium iodide solution to obtain a gallium iodide solution; the remaining metal gallium is weighed to be 14.8 g, and the molar ratio of the amount of metal gallium participating in the reaction to the amount of iodine added is 1:1.5, which is consistent with the stoichiometric ratio of the reaction, and the added iodine is completely reacted;

[0100] (2) Obtaining a methyl magnesium iodide solution: Under an inert atmosphere, 184.6 g of methyl iodide is slowly added dropwise to a mixture of 31.6 g of metallic magnesium and 400 g of isoamyl ether at 60° C. for 3 hours; after the addition is complete, the reaction is continued at about 70° C. for 4 hours to obtain a methyl magnesium iodide solution;

[0101] (3) under an inert atmosphere, heating the methylmagnesium iodide solution prepared in step (2) to 95° C., slowly dropping the gallium iodide solution prepared in step (1) into the methylmagnesium iodide solution for reaction, the dropping time being 5 hours, and after the dropping is completed, continuing the reaction at about 95° C. for 8 hours to obtain a mixed solution containing a complex of trimethylgallium and ether and magnesium iodide;

[0102] The molar ratio of gallium iodide, metallic magnesium and methyl iodide in this embodiment is 1:3:3.

[0103] (4) Under an inert atmosphere, the mixed solution prepared above was subjected to reduced pressure distillation at 120° C. and 10 kPa to obtain a complex of trimethylgallium and isoamyl ether, and the complex was then decomposed by atmospheric distillation. The product receiving temperature was 56° C. Calculated based on the amount of metallic gallium reacted during the preparation of gallium iodide, the yield of trimethylgallium in this example was 79.0%.

[0104] Example 2

[0105] This embodiment provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0106] (1) Obtaining a gallium iodide solution: Under an inert atmosphere, 45.0 g of metal gallium (excess) and 126.5 g of iodine are added to 200 g of isoamyl ether solvent, and reacted at 100° C. for 3 hours to prepare a gallium iodide solution. After the reaction is completed, stirring is continued until the temperature drops below 40° C., and the remaining metal gallium is separated from the gallium iodide solution to obtain a gallium iodide solution; the remaining metal gallium is weighed to be 21.7 g, and the molar ratio of the amount of metal gallium participating in the reaction to the amount of iodine added is 1:1.5, which is consistent with the stoichiometric ratio of the reaction, and the added iodine is completely reacted;

[0107] (2) Obtaining a methyl magnesium iodide solution: Under an inert atmosphere, 146.2 g of methyl iodide is slowly added dropwise to a mixture of 27.5 g of metallic magnesium and 300 g of isoamyl ether at 40 to 80° C. for 2 hours; after the addition is complete, the reaction is continued at about 80° C. for 4 hours to obtain a methyl magnesium iodide solution;

[0108] (3) under an inert atmosphere, heating the methylmagnesium iodide solution prepared in step (2) to 90° C., slowly dropping the gallium iodide solution prepared in step (1) into the methylmagnesium iodide solution for reaction, the dropping time being 4 hours, and after the dropping is completed, continuing the reaction at about 90° C. for 10 hours to obtain a mixed solution containing a complex of trimethylgallium and ether and magnesium iodide;

[0109] The molar ratio of gallium iodide, metallic magnesium and methyl iodide in this embodiment is 1:3.4:3.1.

[0110] (4) Under an inert atmosphere, the mixed solution prepared above was subjected to reduced pressure distillation at 120° C. and 10 kPa to obtain a complex of trimethylgallium and isoamyl ether, and the complex was then decomposed by atmospheric distillation. The product receiving temperature was 56° C. Calculated based on the amount of metallic gallium reacted during the preparation of gallium iodide, the yield of trimethylgallium in this example was 81.8%.

[0111] Example 3

[0112] This embodiment provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0113] (1) Obtaining a gallium iodide solution: Under an inert atmosphere, 34.4 g of metal gallium (excess) and 99.0 g of iodine are added to 200 g of diamyl ether solvent, and reacted at 120° C. for 2 hours to prepare a gallium iodide solution. After the reaction is completed, stirring is continued until the temperature drops below 40° C., and the remaining metal gallium is separated from the gallium iodide solution to obtain a gallium iodide solution; the remaining metal gallium is weighed to be 16.2 g, and the molar ratio of the amount of metal gallium participating in the reaction to the amount of iodine added is 1:1.5, which is consistent with the stoichiometric ratio of the reaction, and the added iodine is completely reacted;

[0114] (2) Obtaining a methyl magnesium iodide solution: Under an inert atmosphere, 118.1 g of methyl iodide is slowly added dropwise to a mixture of 22.1 g of metallic magnesium and 200 g of diamyl ether at 40 to 80° C. for 2 hours; after the addition is complete, the reaction is continued at about 80° C. for 4 hours to obtain a methyl magnesium iodide solution;

[0115] (3) Under an inert atmosphere, the methylmagnesium iodide solution prepared in step (2) is heated to 100° C., and the gallium iodide solution prepared in step (1) is slowly added dropwise to the methylmagnesium iodide solution for reaction. The addition time is 3 hours. After the addition is completed, the reaction is continued at about 100° C. for 9 hours to obtain a mixed solution containing a complex of trimethylgallium and ether and magnesium iodide;

[0116] The molar ratio of gallium iodide, metallic magnesium and methyl iodide in this embodiment is 1:3.5:3.2.

[0117] (4) Under an inert atmosphere, the mixed solution prepared above was subjected to reduced pressure distillation at 140° C. and 10 kPa to obtain a complex of trimethylgallium and isoamyl ether, and the complex was then decomposed by atmospheric distillation. The product receiving temperature was 56° C. Calculated based on the amount of metallic gallium reacted during the preparation of gallium iodide, the yield of trimethylgallium in this example was 77.6%.

[0118] Example 4

[0119] This embodiment provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0120] (1) Obtaining a gallium iodide solution: Under an inert atmosphere, 24.6 g of metal gallium (excess) and 66.0 g of iodine are added to 100 g of methyl phenyl ether solvent, and reacted at 90° C. for 3 hours to prepare a gallium iodide solution. After the reaction is completed, stirring is continued until the temperature drops below 40° C., and the remaining metal gallium is separated from the gallium iodide solution to obtain a gallium iodide solution; the remaining metal gallium is weighed to be 12.5 g, and the molar ratio of the amount of metal gallium participating in the reaction to the amount of iodine added is 1:1.5, which is consistent with the stoichiometric ratio of the reaction, and the added iodine is completely reacted;

[0121] (2) Obtaining a methyl magnesium iodide solution: Under an inert atmosphere, 81.3 g of methyl iodide is slowly added dropwise to a mixture of 13.5 g of metallic magnesium and 200 g of methyl phenyl ether at 40 to 80° C. for 2 hours; after the addition is complete, the reaction is continued at 65° C. for 3 hours to obtain a methyl magnesium iodide solution;

[0122] (3) under an inert atmosphere, heating the methylmagnesium iodide solution prepared in step (2) to 90° C., slowly dropping the gallium iodide solution prepared in step (1) into the methylmagnesium iodide solution for reaction, the dropping time being 3 hours, and after the dropping is completed, continuing the reaction at about 90° C. for 8 hours to obtain a mixed solution containing a complex of trimethylgallium and ether and magnesium iodide;

[0123] The molar ratio of gallium iodide, metallic magnesium and methyl iodide in this embodiment is 1:3.2:3.2.

[0124] (4) Under an inert atmosphere, the mixed solution prepared above was subjected to reduced pressure distillation at 100° C. and 20 kPa to obtain a complex of trimethylgallium and isoamyl ether, and the complex was then decomposed by atmospheric distillation, and the product receiving temperature was 56° C. Calculated based on the amount of metallic gallium reacted during the preparation of gallium iodide, the yield of trimethylgallium in this example was 75.3%.

[0125] Comparative Example 1

[0126] This comparative example provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0127] (1) Obtaining a gallium iodide solution: Under an inert atmosphere, 20 g of metal gallium (excess) and 99.0 g of iodine are added to 200 g of diamyl ether solvent, and reacted at 120° C. for 2 hours to prepare a gallium iodide solution. After the reaction is completed, stirring is continued until the temperature drops below 40° C., and the remaining metal gallium is separated from the gallium iodide solution to obtain a gallium iodide solution; the remaining metal gallium is weighed to be 1.7 g, and the molar ratio of the amount of metal gallium participating in the reaction to the amount of iodine added is 1:1.5, which is consistent with the stoichiometric ratio of the reaction, and the added iodine is completely reacted;

[0128] (2) Obtaining a methyl magnesium iodide solution: Under an inert atmosphere, 118.1 g of methyl iodide is slowly added dropwise to a mixture of 22.1 g of metallic magnesium and 200 g of diamyl ether at 40 to 80° C. for 2 hours; after the addition is complete, the reaction is continued at about 80° C. for 4 hours to obtain a methyl magnesium iodide solution;

[0129] (3) Under an inert atmosphere, the methylmagnesium iodide solution prepared in step (2) is heated to 100° C., and the gallium iodide solution prepared in step (1) is slowly added dropwise to the methylmagnesium iodide solution for reaction. The addition time is 3 hours. After the addition is completed, the reaction is continued at about 100° C. for 9 hours to obtain a mixed solution containing a complex of trimethylgallium and ether and magnesium iodide;

[0130] The molar ratio of gallium iodide, metallic magnesium and methyl iodide in this embodiment is 1:3.5:3.2.

[0131] (4) Under an inert atmosphere, the mixed solution prepared above was subjected to reduced pressure distillation at 140° C. and 10 kPa to obtain a complex of trimethylgallium and isoamyl ether, and the complex was then decomposed by atmospheric distillation. The product receiving temperature was 56° C. Calculated based on the amount of metallic gallium reacted during the preparation of gallium iodide, the yield of trimethylgallium in this example was 76.8%.

[0132] Comparative Example 2

[0133] This comparative example provides a method for preparing trimethylgallium, which is carried out under an inert atmosphere and comprises the following steps:

[0134] (1) obtaining a gallium iodide solution: reacting 24.6 g of metal gallium (excess amount) with 66.0 g of iodine in a molten state for 3 hours under an inert atmosphere, then adding the reactant to 100 g of methyl phenyl ether solvent to prepare a gallium iodide solution, and continuing to stir until the temperature drops below 40° C. after the reaction is completed, separating the remaining metal gallium from the gallium iodide solution to obtain a gallium iodide solution; the remaining metal gallium weighs 17.1 g, the molar ratio of the amount of metal gallium participating in the reaction to the amount of iodine added is less than the stoichiometric ratio of the reaction of 1:1.5, and the added iodine is not completely reacted;

[0135] (2) Obtaining a methyl magnesium iodide solution: Under an inert atmosphere, 81.3 g of methyl iodide is slowly added dropwise to a mixture of 13.5 g of metallic magnesium and 200 g of methyl phenyl ether at 40 to 80° C. for 2 hours; after the addition is complete, the reaction is continued at 65° C. for 3 hours to obtain a methyl magnesium iodide solution;

[0136] (3) under an inert atmosphere, heating the methylmagnesium iodide solution prepared in step (2) to 90° C., slowly dropping the gallium iodide solution prepared in step (1) into the methylmagnesium iodide solution for reaction, the dropping time being 3 hours, and after the dropping is completed, continuing the reaction at about 90° C. for 8 hours to obtain a mixed solution containing a complex of trimethylgallium and ether and magnesium iodide;

[0137] The molar ratio of gallium iodide, metallic magnesium and methyl iodide in this embodiment is 0.6:3.2:3.2.

[0138] (4) Under an inert atmosphere, the mixed solution prepared above was subjected to reduced pressure distillation at 100° C. and 20 kPa to obtain a complex of trimethylgallium and isoamyl ether, and the complex was then decomposed by atmospheric distillation, and the product receiving temperature was 56° C. Calculated based on the amount of metallic gallium reacted during the preparation of gallium iodide, the yield of trimethylgallium in this example was 70.6%.

[0139] From the results of Examples 1 to 4 and Comparative Examples 1 to 2, it can be seen that in the trimethylgallium preparation method used in Examples 1 to 4, excess gallium and iodine are reacted in a solvent, the iodine reacts completely, and the reaction efficiency of generating gallium iodide is high, resulting in a higher yield of subsequent trimethylgallium. Compared with Example 3, Comparative Example 1 is different in that the amount of metal gallium added is less, but the reaction amount of the added iodine is still excessive, so the amount of gallium iodide generated is not much different from that of Example 3, and the final yield of trimethylgallium is 76.8%. Compared with Example 4, Comparative Example 2 is different in that no solvent is used in the gallium iodide reaction, but the metal gallium and iodine are directly placed in an inert atmosphere for reaction, the reaction is difficult to mix, the reaction surface area of ​​metal gallium and iodine sublimation gas is small, and the reaction rate is not high, so the iodine reacts incompletely, and the amount of gallium iodide generated is significantly lower than that of Example 4, so the yield of trimethylgallium in the subsequent reaction is low.

[0140] In summary, the Grignard reagent method with higher safety is adopted in the embodiment of the present application. On the basis of the Grignard reagent method, the cost of the gallium halide raw materials used and the requirements for the use and storage conditions of the raw materials are further reduced. Gallium iodide is prepared by heating and refluxing reaction of metallic gallium and iodine in an organic solvent. It can also avoid the problem that solid iodine and metallic gallium are difficult to mix evenly, and when solid iodine is heated and sublimated into a gaseous state, it reacts with metallic gallium only on the metal surface, and the gas-solid reaction efficiency is not high. Secondly, organic ethers are used as solvents, and gallium iodide ether solutions are prepared by heating and refluxing reaction in ether solvents, which can be directly used in the next step to react with the ether solution of Grignard reagent to prepare trimethylgallium, which is beneficial to the continuity of the synthesis reaction. Finally, in the present invention, ether solvents with higher boiling points are used, and the whole reaction process is stable, simple to operate, easy to control, and beneficial to improving safety.

[0141] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. It will be apparent to those skilled in the art that various modifications to these embodiments are possible, and the general principles defined in the present application can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown in the present application, but will conform to the widest range consistent with the principles and novel features applied for by the present application.

Claims

1. A method for preparing trimethylgallium, the method being carried out under an inert atmosphere, comprising the following steps: Placing metal gallium and halogen in a solvent for a first reaction to obtain a reaction mixture; separating the reaction mixture to obtain a gallium halide solution; Using the gallium halide solution to prepare trimethylgallium; Wherein, the halogen element is bromine element or iodine element; The parameters of the first reaction include at least one of the following: a reaction temperature of 50° C. to 120° C., and a reaction time of 0.5 h to 3 h.

2. According to the preparation method of claim 1, the molar ratio of the metallic gallium to the halogen element is greater than 1:1.

5.

3. The preparation method according to claim 1, wherein the gallium halide solution is used to prepare trimethylgallium, specifically comprising: A methylmagnesium halide solution is obtained; performing a second reaction on the gallium halide solution and the methylmagnesium halide solution to obtain a solution containing a trimethylgallium complex; The solution containing the trimethylgallium complex is subjected to a decomposition reaction to obtain trimethylgallium.

4. The preparation method according to claim 3, wherein the molar ratio of the gallium halide to the methylmagnesium halide is 1:(3-3.8).

5. The preparation method according to claim 3, wherein the methyl magnesium halide solution is obtained, specifically comprising: mixing magnesium with a solvent to obtain a mixture; subjecting the mixture to a third reaction with methyl halide to obtain a methyl magnesium halide solution; Wherein, the temperature of the third reaction is 40°C to 80°C.

6. The preparation method according to claim 1 or 5, wherein the solvent is an organic ether.

7. The preparation method according to claim 6, wherein the solvent comprises at least one of the following: isopentyl ether, dipentyl ether and methyl phenyl ether.

8. The preparation method according to claim 3, wherein the gallium halide solution and the methyl magnesium halide solution are subjected to a second reaction to obtain a solution containing a trimethyl gallium complex, specifically comprising: adding the gallium halide solution dropwise to the methylmagnesium halide solution to perform a second reaction to obtain a solution containing a trimethylgallium complex; Wherein, the time of the dropwise addition is 2h to 6h; The parameters of the second reaction include at least one of the following: a reaction temperature of 50° C. to 110° C., and a reaction time of 6 h to 10 h.

9. The preparation method according to claim 3, wherein the solution containing the trimethylgallium complex is subjected to a decomposition reaction to obtain trimethylgallium, specifically comprising: The solution containing the trimethylgallium complex is subjected to reduced pressure distillation to obtain the trimethylgallium complex; The trimethylgallium complex is distilled at normal pressure to obtain trimethylgallium.

10. The preparation method according to claim 9, wherein the pressure of the reduced pressure distillation is 10 kPa to 20 kPa and the temperature is 90° C. to 150° C.; and / or, The receiving temperature of the product of the atmospheric distillation is 55°C to 60°C.

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