Method for preparing high-purity triethylindium

Abstract

The application discloses a preparation method of high-purity triethyl indium and relates to the technical field of metal organic source synthesis. Nowadays, high-purity indium source is a key raw material for MOCVD technology. Currently, the commonly used indium source is trimethyl indium. However, trimethyl indium is solid at room temperature, which easily causes problems such as excessive solid indium source residue, low solid molecule overflow rate, and hardening and channeling. Therefore, the solid indium source is worse than liquid source in vapor saturation and source content stability. In the application, the halide of indium and triethyl aluminum are reacted to generate triethyl indium under the protection of inert gas. The crude triethyl indium is purified by reduced pressure distillation. The finished triethyl indium is obtained by further purification. The whole process is simple in operation. In addition, the purity of the product is improved under the protection of inert gas, so that the preparation of triethyl indium is not affected by other solvents.

Description

Technical Field

[0001] This invention relates to the field of organometallic source synthesis technology, specifically a method for preparing high-purity triethylin. Background Technology

[0002] MO sources, or high-purity organometallic sources (also known as high-purity organometallic compounds), typically have a purity of 99.9999% (6N) or higher. They are core raw materials for the fabrication of LEDs, next-generation solar cells, phase-change memories, semiconductor lasers, and radio frequency integrated circuit chips, playing a crucial role in semiconductor lighting, information communication, and aerospace. The LED industry is a major application area for MO sources, accounting for over 90% of all MO source applications. At one time, foreign countries considered MO sources as a controlled export commodity to my country. Therefore, the successful domestic production of MO sources has extremely important strategic significance, greatly promoting the development of my country's microelectronics and optoelectronics industries.

[0003] In response, Chinese patent application number CN110452257A discloses a method for preparing triethylin, which involves reacting the Grignard reagent ethyl magnesium iodide with indium trihalide to synthesize triethylin, followed by distillation to obtain the finished triethylin. However, this method actually yields the diethyl ether ligand of triethylin, which is difficult to completely remove by ordinary distillation or fractional distillation.

[0004] In response, Chinese patent application number CN104860972B discloses the following steps: ① preparing crude trimethylindium using diethyl ether as a solvent; ② purifying the crude trimethylindium obtained in step ①, wherein the purification method includes purifying the crude trimethylindium using a first chromatography column; and the stationary phase used in the first chromatography column is grafted silica, wherein the grafted silica is silica with tri-n-octylamine grafted onto its surface. The preparation method of this invention uses two steps, synthesis and separation, to obtain trimethylindium with a purity of 6N; in particular, the purification method combines solid-liquid separation, loading a specific ligand onto silica, which not only simplifies the operation but also further improves the purification effect.

[0005] High-purity indium sources are currently a key raw material for MOCVD technology. The most commonly used indium source is trimethylindium. However, since trimethylindium is solid at room temperature, it is easy to cause excessive solid indium source residue and low solid molecule diffusion rate, as well as problems such as caking and channeling. As a result, solid indium sources are inferior to liquid sources in terms of vapor saturation and source content stability.

[0006] To address the aforementioned issues, a method for preparing high-purity triethylin is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a method for preparing high-purity triethylin, which solves the problems of excessive solid indium source residue and low solid molecule spillover rate in the prior art, which are prone to caking and channeling.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing high-purity triethylin, comprising the following steps: adding indium halide to a reaction apparatus under inert gas protection, setting up a reflux device, starting the stirrer, and adding triethylaluminum dropwise inside the apparatus, raising the temperature inside the reaction apparatus, maintaining the system temperature, stopping the stirring reaction, and performing vacuum distillation on the remaining reaction solution.

[0009] Distillation produces crude triethylin, which is then subjected to vacuum distillation to extract the finished product, triethylin.

[0010] The finished product of triethylin was extracted and sampled for testing to determine its purity.

[0011] Preferably, all operations are carried out under the protection of an inert gas, wherein the water and oxygen content of the inert gas is less than 1 ppm.

[0012] Preferably, before adding indium halide, it is dried with thionyl chloride, excess thionyl chloride is filtered off, and finally it is subjected to absolute pressure at around 100°C for 6-8 hours.

[0013] Preferably, the indium halide is one of indium chloride, indium bromide, indium iodide, and indium fluoride, with indium chloride being the preferred choice.

[0014] Preferably, the internal temperature of the reaction apparatus is raised, and the reaction temperature is controlled at 70℃-90℃, with 80℃ being the most preferred.

[0015] Preferably, the reaction is carried out in the reaction apparatus with stirring for 3-6 hours, with 5 hours being the most preferred.

[0016] Preferably, the reaction solution is subjected to vacuum distillation, with the pressure controlled at 5 Torr-10 Torr, preferably 5 Torr, to collect the fraction at 70°C-80°C.

[0017] Preferably, the triethylin product undergoes NMR and ICP testing.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. The method for preparing high-purity triethylin provided by the present invention involves reacting indium halides with triethylaluminum under inert gas protection to generate triethylin, purifying it to crude triethylin by vacuum distillation, and then further purifying it to obtain the finished triethylin product. The entire process is simpler to operate, and the purity of the product is improved under inert gas protection, so that the preparation of triethylin is not affected by the purity of other solvents. Attached Figure Description

[0020] Figure 1 This is a flowchart of the synthesis of triethylindium according to the present invention;

[0021] Figure 2 This is a schematic diagram of the 1H NMR spectrum of the triethylin product of this invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] To further understand the content of this invention, a detailed description of the invention will be provided in conjunction with the accompanying drawings.

[0024] Combination Figures 1-2 This invention provides a method for preparing high-purity triethylindium, comprising the following steps: all operations are carried out under the protection of an inert gas, wherein the water and oxygen content of the inert gas is less than 1 ppm; under the protection of an inert gas, indium halide is added to the reaction apparatus, the indium halide being one of indium chloride, indium bromide, indium iodide, and indium fluoride, with indium chloride being preferred; before adding the indium halide, it is dried by thionyl chloride, and excess thionyl chloride is filtered off; finally, the mixture is subjected to absolute pressure at approximately 100°C for 6-8 hours, a reflux apparatus is set up, stirring is started, and triethylaluminum is added dropwise inside the apparatus; the internal temperature of the reaction apparatus is raised and maintained at 70°C-90°C, preferably 80°C; the stirring reaction is completed, and the stirring reaction time is 3-6 hours, preferably 5 hours; the remaining reaction solution is subjected to vacuum distillation, the reaction solution is purified by vacuum distillation, the pressure is controlled at 5 Torr-10 Torr, preferably 5 Torr, and the fraction collected at 70°C-80°C is received.

[0025] Distillation produces crude triethylin, which is then subjected to vacuum distillation to extract the finished product, triethylin.

[0026] The extracted triethylin product was analyzed by NMR and ICP.

[0027] This invention provides a method for preparing high-purity triethylin, the specific preparation method and its parameter steps are as follows:

[0028] Example 1:

[0029] according to Figure 1 and Figure 2 As shown, the preparation method of high-purity triethylin includes the following steps;

[0030] 1. Under inert gas protection, add 221.1g of indium chloride to a 1L round-bottom four-necked flask, set up an atmospheric pressure reflux device, start stirring, and then add 359.6g of triethylaluminum dropwise. After the addition is complete, heat the bottom flask to 70℃ and stir for 3h.

[0031] 2. After the stirring reaction is completed, vacuum distillation is carried out, with the pressure controlled at 5 Torr-10 Torr. The fraction collected at 70℃-80℃ is the crude triethylin product, with a total of 176.8g collected. High-purity triethylin product can be obtained by vacuum distillation.

[0032] 3. The product undergoes NMR and ICP testing;

[0033] In this case, the yield of triethylin was 87.5%. The product was analyzed by a JNM-ECZ400S nuclear magnetic resonance spectrometer: 1H NMR (400MHz, C6D6) δ: 0.49 (q, 6H); 1.40 (t, 9H). Inductively coupled plasma atomic emission spectrometry (Optima8000) showed that all inorganic elements were <1ppm, and the purity reached 6N.

[0034] Example 2:

[0035] according to Figure 1 and Figure 2 As shown, the preparation method of high-purity triethylin includes the following steps;

[0036] 1. Under inert gas protection, add 331.5g of indium chloride to a 1L round-bottom four-necked flask, set up an atmospheric pressure reflux device, start stirring, and then add 539.5g of triethylaluminum dropwise. After the addition is complete, heat the bottom flask to 80℃ and stir for 5 hours.

[0037] 2. After the stirring reaction is complete, perform vacuum distillation, with the pressure controlled at 5 Torr-10 Torr, and collect the fraction at 70℃-80℃, which is the crude triethylin product. A total of 276g was collected. After vacuum distillation, the high-purity triethylin product can be obtained.

[0038] 3. The product undergoes NMR and ICP testing;

[0039] In this case, the triethylin synthesis yield was 91.1%. The product was analyzed by a JNM-ECZ400S nuclear magnetic resonance spectrometer: 1H NMR (400MHz, C6D6) δ 0.49 (q, 6H); 1.40 (t, 9H). Inductively coupled plasma atomic emission spectrometry (Optima8000) detected all inorganic elements <1ppm, and the purity reached 6N.

[0040] Example 3:

[0041] according to Figure 1 and Figure 2As shown, the preparation method of high-purity triethylin includes the following steps;

[0042] 1. Under inert gas protection, add 531g.8g of indium bromide to a 1L round-bottom four-necked flask, set up an atmospheric pressure reflux device, start stirring, and then add 539.5g of triethylaluminum dropwise. After the addition is complete, heat the bottom flask to 70℃ and stir for 5h.

[0043] 2. After the stirring reaction is completed, vacuum distillation is carried out, with the pressure controlled at 5 Torr-10 Torr. The fraction collected at 70℃-80℃ is the crude triethylin product, with a total of 273g collected. High-purity triethylin product can be obtained by vacuum distillation.

[0044] 3. The product undergoes NMR and ICP testing;

[0045] In this case, the triethylin synthesis yield was 90%. The product was analyzed by a JNM-ECZ400S nuclear magnetic resonance spectrometer: 1H NMR (400MHz, C6D6) δ: 0.49 (q, 6H); 1.40 (t, 9H). Inductively coupled plasma atomic emission spectrometry (Optima8000) detected that all inorganic elements were <1ppm, and the purity reached 6N.

[0046] Example 4:

[0047] according to Figure 1 and Figure 2 As shown, the preparation method of high-purity triethylin includes the following steps;

[0048] 1. Under inert gas protection, add 343.6g of indium fluoride to a 2L round-bottom four-necked flask, set up an atmospheric pressure reflux device, start stirring, and then add 719.3g of triethylaluminum dropwise. After the addition is complete, heat the bottom flask to 80℃ and stir for 6 hours.

[0049] 2. After the stirring reaction is completed, vacuum distillation is carried out, with the pressure controlled at 5-10 Torr. The fraction collected at 70-80℃ is the crude triethylin product, with a total of 366.8g collected. High-purity triethylin product can be obtained by vacuum distillation.

[0050] 3. The product undergoes NMR and ICP testing;

[0051] In this case, the triethylin synthesis yield was 90.8%. The product was analyzed by a JNM-ECZ400S nuclear magnetic resonance spectrometer: 1H NMR (400MHz, C6D6) δ: 0.49 (q, 6H); 1.40 (t, 9H). Inductively coupled plasma atomic emission spectrometry (Optima8000) detected that all inorganic elements were <1ppm, and the purity reached 6N.

[0052] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0053] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing high-purity triethylin, characterized in that: Includes the following steps: Indium halide was added to the reaction apparatus under inert gas protection, a reflux device was set up, the stirrer was turned on, and triethylaluminum was added dropwise to the inside of the apparatus. The temperature inside the reaction apparatus was raised and maintained. After the stirring reaction was completed, the remaining reaction solution was distilled under reduced pressure. Distillation produces crude triethylin, which is then subjected to vacuum distillation to produce the finished triethylin product. The finished product of triethylin was extracted and sampled for testing to determine its purity.

2. The method for preparing high-purity triethylin according to claim 1, characterized in that: All operations were carried out under the protection of inert gas, in which the water and oxygen content of the inert gas was less than 1 ppm.

3. The method for preparing high-purity triethylin according to claim 1, characterized in that: The indium halide is one of indium chloride, indium bromide, indium iodide, and indium fluoride.

4. The method for preparing high-purity triethylin according to claim 1, characterized in that: The internal temperature of the reaction apparatus is raised, and the reaction temperature is controlled between 70℃ and 90℃.

5. The method for preparing high-purity triethylin according to claim 1, characterized in that: The reaction is stirred in the reaction apparatus for 3-6 hours.

6. The method for preparing high-purity triethylin according to claim 1, characterized in that: The reaction solution is subjected to vacuum distillation, with the pressure controlled at 5-10 Torr, and the fraction collected at 70-80℃ is obtained.

7. The method for preparing high-purity triethylin according to claim 1, characterized in that: The finished triethylin product was subjected to NMR and ICP testing.

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