A process for the preparation of bis(acetylacetone)tin

Abstract

The application discloses a preparation method of bis(acetylacetone) tin, and the preparation method comprises the following steps: under an inert atmosphere, (1) mixing acetylacetone alkali metal salt, acetylacetone and a solvent to obtain a reaction solution; (2) adding stannous chloride into the reaction solution prepared in the step (1) and stirring to react; (3) after the reaction is completed, removing the solvent under reduced pressure to obtain a solid-liquid mixture, and then distilling under reduced pressure to obtain the bis(acetylacetone) tin. In the application, the organic amine used as an acid-binding agent in the traditional preparation method of the bis(acetylacetone) tin is replaced by the acetylacetone alkali metal salt, and by controlling the adding sequence of the reactants, the bis(acetylacetone) tin can be prepared, and the yield of the product is greatly improved. In addition, compared with the traditional preparation method, the preparation method does not need to filter the by-product organic amine hydrochloride, is favorable for simplifying the process, and is suitable for mass preparation of the bis(acetylacetone) tin.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of organic synthesis, in particular to a preparation method of bis(acetylacetone) tin. BACKGROUND

[0002] Stannous oxide (SnO) is an important semiconductor metal oxide, which is widely used in the fields of catalysts, electroplating and glass industry. As a negative electrode material of lithium batteries, the performance of stannous oxide is higher than that of carbon material as a negative electrode of a battery in terms of volume specific energy and mass specific energy, and therefore, stannous oxide has attracted wide attention from researchers. In recent years, the emergence of nanoscale stannous oxide enables stannous oxide to have a more long-term application development. Due to the unique optical and electrical properties, stannous oxide is favored by more and more people in the fields of catalysis, sensing and optoelectronic devices. Bis(acetylacetone) tin is a precursor source required for preparing a SnO thin film by an atomic layer deposition method. A traditional preparation method is as follows: stannous chloride and tert-butyl alcohol are used as raw materials, the two are mixed in an organic solvent, diethylamine or triethylamine is added dropwise to bind hydrogen chloride generated in the reaction to form an organic amine hydrochloride, the organic amine hydrochloride is filtered off after the reaction is completed, the filtrate is collected, the solvent in the filtrate is removed, and a crude product is obtained by vacuum distillation.

[0003] In the above reaction process, the by-product organic amine hydrochloride needs to be filtered, the operation is complicated, a large amount of time is consumed, and the yield of the product is low. If the organic amine hydrochloride is not filtered, the organic amine hydrochloride will decompose and condense at the product collection end in the subsequent vacuum distillation process, which affects the purity and collection of the product. SUMMARY

[0004] The application provides a preparation method of bis(acetylacetone) tin. Alkali metal acetylacetone salt is used as an acid-binding agent to replace the organic amine acid-binding agent in the traditional preparation process of bis(acetylacetone) tin. The generation of the organic amine hydrochloride in the reaction process is avoided, the process is simplified, the yield of bis(acetylacetone) tin is significantly improved, and the prepared bis(acetylacetone) tin has a high metal purity of 5N.

[0005] To solve the above technical problems, the application provides the following technical scheme:

[0006] The application provides a preparation method of bis(acetylacetone) tin, which comprises the following steps:

[0007] (1) mixing alkali metal acetylacetone salt, acetylacetone and a solvent to obtain a reaction solution;

[0008] (2) adding stannous chloride into the reaction solution prepared in step (1) and stirring to react;

[0009] (3) After the reaction is completed, the solvent is removed under reduced pressure to obtain a solid-liquid mixture, and then the bis(acetylacetone) tin is obtained by distillation under reduced pressure.

[0010] Further, in step (1), the acetylacetone alkali metal salt is selected from one or more of sodium acetylacetone, potassium acetylacetone, and lithium acetylacetone.

[0011] Further, in step (1), the molar ratio of the acetylacetone alkali metal salt to acetylacetone is preferably 1:1-3.

[0012] Further, in step (1), the solvent is selected from one or more of toluene, n-hexane, and diethyl ether, and more preferably toluene.

[0013] Further, in step (2), the stannous chloride is added to the reaction solution at a temperature of -20-20°C. Adding stannous chloride to the reaction solution generates heat. To avoid the risk of excessive heat release when adding stannous chloride, the temperature of the reaction system is controlled at a relatively low temperature. To avoid the influence of a too low reaction system temperature on the reaction rate, more preferably, the stannous chloride is added to the reaction solution at a temperature of -20-20°C.

[0014] Further, in step (2), the molar ratio of the stannous chloride to acetylacetone is preferably 1:2-5. Adding excess acetylacetone promotes the forward reaction to improve the yield. When the amount of acetylacetone is increased to 5 times the molar amount of stannous chloride, further increasing the amount of acetylacetone cannot continue to improve the yield. Therefore, to improve the yield while controlling the cost, the molar ratio of stannous chloride to acetylacetone is preferably controlled at 1:2-5.

[0015] Further, in step (2), the stirring reaction temperature is preferably 0-30°C, and the stirring reaction time is not less than 3h.

[0016] Further, in step (3), in the step of removing the solvent under reduced pressure: the pressure is preferably 0.5-5 Torr, and the temperature is preferably 0-50°C, and more preferably 40-50°C.

[0017] Further, in step (3), in the step of distillation under reduced pressure: the pressure is preferably 0.02-5 Torr, and the temperature is preferably 100-190°C, and more preferably, the pressure is 0.5 Torr, and the temperature is 150°C. If the distillation temperature is too high, the distillation speed will be too fast, reducing the purity of the product. If the temperature is too low, part of the product will not be distilled out, reducing the yield of the product. To ensure the yield and purity of the product, the distillation temperature needs to be controlled in an appropriate range, for example, the pressure is 0.02-5 Torr, and the temperature is 100-190°C.

[0018] Further, the preparation method further comprises subjecting the bis(acetylacetone)tin prepared in step (3) to a reduced pressure distillation treatment; in the step of the reduced pressure distillation treatment, the pressure is preferably 0.02-5 Torr, and the temperature is preferably 100-190°C, and more preferably, the pressure is 0.5 Torr and the temperature is 150°C. The product obtained after the above-mentioned reduced pressure distillation treatment has low chemical purity and contains a small amount of impurities and solvents, and therefore, the crude product after the reduced pressure distillation treatment is subjected to a reduced pressure distillation treatment by a reduced pressure distillation device comprising a condensation reflux stab column, so as to increase the purity of the product to 5N.

[0019] Further, the metal purity of the bis(acetylacetone)tin after the above-mentioned reduced pressure distillation treatment is not less than 5N.

[0020] Further, the gas in the protective atmosphere is nitrogen and / or argon.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] In the present application, the organic amine acid-binding agent used in the traditional preparation process of bis(acetylacetone)tin is replaced by acetylacetone alkali metal salt, so that the generation of organic amine hydrochloride in the reaction process is avoided, thereby simplifying the process flow. It is unexpectedly found that, compared with the traditional preparation process, the yield of bis(acetylacetone)tin prepared by the above-mentioned preparation method can be effectively improved, and the prepared bis(acetylacetone)tin has a high metal purity of 5N. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 NMR hydrogen spectrum of bis(acetylacetone)tin prepared in Example 1. DETAILED DESCRIPTION

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. The use of the term "including" or "containing" in the description herein means that the components listed are included or contained, but not excluding other components. The use of the term "including" or "containing" can also be replaced by the closed term "consisting of" or "consisting only of".

[0025] The present application will be further described in conjunction with specific examples, so that those skilled in the art can better understand the present application and implement it. However, the examples are not intended to limit the present application.

[0026] Example 1

[0027] This example relates to the preparation of bis(acetylacetone)tin, and the specific preparation process is as follows:

[0028] (1) Under nitrogen protection, a solution of sodium acetylacetonate (1 mol, 122.12 g) in acetylacetone (2.5 mol, 256.72 mL) and toluene (7.5 mol, 797.15 mL) were added to a 2 L reaction bottle to obtain a reaction solution;

[0029] (2) Stannous chloride (0.5 mol, 94.81 g) was added to the reaction solution prepared in step (1) through a solid sample feeder, and stirred at room temperature for 3 hours;

[0030] (3) After the reaction was completed, the solvent was removed at 50°C under reduced pressure (pressure was 0.5 Torr) to obtain a solid-liquid mixture; then distilled at 150°C under reduced pressure (pressure was 0.5 Torr) to obtain a yellow transparent liquid;

[0031] (4) The yellow transparent liquid prepared in step (3) was subjected to vacuum rectification (pressure was 0.5 Torr, temperature was 150°C) to obtain a yellow transparent liquid (134.69 g, 0.425 mol), and the yield was 85%.

[0032] The product prepared in this example was subjected to nuclear magnetic characterization and metal purity test, and the results are as follows:

[0033] The nuclear magnetic hydrogen spectrum of the product is shown in Figure 1 The target product bis(acetylacetone)tin was prepared; the ICP-MS detection results of the product showed that the metal purity was 5N, and the content of impurity metals was as follows: Li: 1.468 ppb, Na: 3.641 ppb, Mg: 17.543 ppb, Al: 21.025 ppb, K: 142.674 ppb, Ca: 16.94 ppb, Ti: 12.188 ppb, V: 2.633 ppb, Cu: 28.075 ppb, Zn: 7.018 ppb, Ge: 773.886 ppb, Cd: 38.779 ppb, Ba: 242.222 ppb, W: 304.894 ppb.

[0034] Example 2

[0035] This example relates to the preparation of bis(acetylacetone)tin, and the specific preparation process is as follows:

[0036] (1) Under the protection of nitrogen, a solution of sodium acetylacetonate (1 mol, 122.12 g) in acetylacetone (2.5 mol, 256.72 mL) and n-hexane (7.5 mol, 980.75 mL) was added to a 2 L reaction flask to obtain a reaction solution;

[0037] (2) Stannous chloride (0.5 mol, 94.81 g) was added to the reaction solution prepared in step (1) through a solid sample feeder, and stirred at room temperature for 3 hours;

[0038] (3) After the reaction was completed, the solvent was removed at 25°C under reduced pressure (0.5 Torr), to obtain a solid-liquid mixture; then distillation was carried out at 150°C under reduced pressure (0.5 Torr), to obtain a yellow transparent liquid;

[0039] (4) The yellow transparent liquid prepared in step (3) was subjected to vacuum rectification (0.5 Torr, 150°C), to obtain a yellow transparent liquid (110.92 g, 0.35 mol), with a yield of 70%.

[0040] The product prepared in this example was subjected to nuclear magnetic characterization and metal purity test. The nuclear magnetic characterization result showed that the product was bis(acetylacetonato)tin; the ICP-MS detection result of the product showed that the metal purity was 5N.

[0041] Example 3

[0042] This example relates to the preparation of bis(acetylacetonato)tin, which is different from example 1 in that different solvents are used to prepare bis(acetylacetonato)tin, and the specific preparation process is as follows:

[0043] (1) Under the protection of nitrogen, a solution of sodium acetylacetonate (1 mol, 122.12 g) in acetylacetone (2.5 mol, 256.72 mL) and n-hexane (7.5 mol, 980.75 mL) was added to a 2 L reaction flask to obtain a reaction solution;

[0044] (2) Stannous chloride (0.5 mol, 94.81 g) was added to the reaction solution prepared in step (1) through a solid sample feeder, and stirred at room temperature for 3 hours;

[0045] (3) After the reaction was completed, the solvent was removed at 25°C under reduced pressure (0.5 Torr), to obtain a solid-liquid mixture; then distillation was carried out at 150°C under reduced pressure (0.5 Torr), to obtain a yellow transparent liquid;

[0046] (4) The yellow transparent liquid prepared in step (3) was subjected to vacuum rectification (0.5 Torr, 150°C), to obtain a yellow transparent liquid (110.92 g, 0.35 mol), with a yield of 70%.

[0047] The product prepared in this example was subjected to nuclear magnetic characterization and metal purity test. The nuclear magnetic characterization result showed that the product was bis(acetylacetone)tin; the ICP-MS detection result of the product showed that the metal purity was 5N.

[0048] Example 4

[0049] This example relates to the preparation of bis(acetylacetone)tin, which is different from example 1 in that different acetylacetone alkali metal salt is used to prepare bis(acetylacetone)tin, and the specific preparation process is as follows:

[0050] (1) Under nitrogen protection, acetylacetone lithium (1 mol, 106.05 g) solution in acetylacetone (2.5 mol, 256.72 mL) and toluene (7.5 mol, 797.15 mL) were added to a 2 L reaction bottle to obtain a reaction liquid;

[0051] (2) Stannous chloride (0.5 mol, 94.81 g) was added to the reaction liquid prepared in step (1) through a solid feeder, and stirred at room temperature for 3 hours;

[0052] (3) After the reaction was completed, the solvent was removed at 50°C under reduced pressure (pressure was 0.5 Torr) to obtain a solid-liquid mixture; then distilled at 150°C under reduced pressure (pressure was 0.5 Torr) to obtain a yellow transparent liquid;

[0053] (4) The yellow transparent liquid prepared in step (3) was subjected to vacuum rectification (pressure was 0.5 Torr, temperature was 150°C) to obtain a yellow transparent liquid (137.86 g, 0.435 mol), and the yield was 87%.

[0054] The product prepared in this example was subjected to nuclear magnetic characterization and metal purity test. The nuclear magnetic characterization result showed that the product was bis(acetylacetone)tin; the ICP-MS detection result of the product showed that the metal purity was 5N.

[0055] Example 5

[0056] This example relates to the preparation of bis(acetylacetone)tin, which is different from example 1 in that different acetylacetone alkali metal salt is used to prepare bis(acetylacetone)tin, and the specific preparation process is as follows:

[0057] (1) Under nitrogen protection, acetylacetone lithium (1 mol, 106.05 g) solution in acetylacetone (2.5 mol, 256.72 mL) and toluene (7.5 mol, 797.15 mL) were added to a 2 L reaction bottle to obtain a reaction liquid;

[0058] (2) tin chloride (0.5 mol, 94.81 g) was added to the reaction solution prepared in step (1) by a solid feeder, and stirred at room temperature for 3 hours;

[0059] (3) after the reaction was completed, the solvent was removed at 50°C under reduced pressure (0.5 Torr), to obtain a solid-liquid mixture; then distillation was carried out at 150°C under reduced pressure (0.5 Torr), to obtain a yellow transparent liquid;

[0060] (4) the yellow transparent liquid prepared in step (3) was subjected to vacuum rectification (0.5 Torr, 150°C), to obtain a yellow transparent liquid (129.94 g, 0.41 mol), with a yield of 82%.

[0061] The product prepared in this example was subjected to nuclear magnetic characterization and metal purity test. The nuclear magnetic characterization result showed that the product was bis(acetylacetone)tin; the ICP-MS detection result of the product showed that the metal purity was 5N.

[0062] Comparative Example 1

[0063] This comparative example relates to the preparation of bis(acetylacetone)tin. Tin chloride was directly reacted with sodium acetylacetonate. The specific preparation process was as follows:

[0064] Under nitrogen protection, tin chloride (0.5 mol, 94.81 g) and toluene (7.5 mol, 797.15 mL) were added to a 2L reaction bottle, sodium acetylacetonate (1 mol, 122.12 g) was added to the reaction solution by a solid feeder, stirred at room temperature for 3 hours, the solvent was removed at 50°C under reduced pressure (0.5 Torr), to obtain a solid-liquid mixture, then distillation was carried out at 150°C under reduced pressure (0.5 Torr), and the target product was not obtained.

[0065] Comparative Example 2

[0066] This comparative example uses a traditional preparation method to prepare bis(acetylacetone)tin. The specific preparation process was as follows:

[0067] (1) under nitrogen protection, tin chloride (0.5 mol, 94.81 g) was added to a 2L reaction bottle, then toluene (7.5 mol, 797.15 mL), diethylamine (1 mol, 104.48 mL) and acetylacetone (2.5 mol, 256.72 ml) were sequentially added to the reaction bottle, and stirred at room temperature for 3 hours;

[0068] (2) the by-product organic amine hydrochloride was filtered under nitrogen protection, then the filtrate was subjected to solvent removal at 50°C under reduced pressure (0.5 Torr), to obtain a solid-liquid mixture; then distillation was carried out at 150°C under reduced pressure (0.5 Torr), to obtain a yellow transparent liquid;

[0069] (3) The yellow transparent liquid prepared in step (2) is subjected to vacuum rectification (pressure: 0.5 Torr, temperature: 150 DEG C) to obtain a yellow transparent liquid (82.40 g, 0.26 mol), with a yield of 52%

[0070] The product prepared in the example is subjected to nuclear magnetic characterization and metal purity test, the nuclear magnetic characterization result shows that the product is bis(acetylacetone)tin; the ICP-MS detection result of the product shows that the metal purity is 5N.

[0071] As can be seen from the above, the organic amine acid-binding agent in the traditional preparation process of bis(acetylacetone)tin is replaced by acetylacetone alkali metal salt in the application, so that no organic amine hydrochloride salt which needs to be separated is generated in the preparation process, which is beneficial to simplify the process flow, and it is accidentally found that the use of acetylacetone alkali metal salt as an acid-binding agent can significantly improve the yield of the target product. As can be seen from examples 1-5, the solvent of the reaction system and the type of acetylacetone alkali metal salt will affect the yield of the product, and the type of solvent has a greater impact on the yield, when the solvent is toluene and the acid-binding agent is acetylacetone lithium, the yield of the target product bis(acetylacetone)tin is as high as 87%.

[0072] The above examples are only preferred examples for fully illustrating the application, and the protection scope of the application is not limited thereto. Any equivalent replacement or transformation of the application made by the person skilled in the art on the basis of the application is within the protection scope of the application. The protection scope of the application is subject to the claims.

Claims

1. A process for the preparation of bis(acetylacetone)tin, characterized in that, The preparation method comprises the following steps: (1) mixing acetylacetone alkali metal salt, acetylacetone and a solvent to obtain a reaction solution; (2) adding stannous chloride to the reaction solution prepared in step (1) and stirring to react; (3) after the reaction is completed, the solvent is removed under reduced pressure to obtain a solid-liquid mixture, and then the double (acetylacetone) tin is obtained by distillation under reduced pressure; in the step of removing the solvent under reduced pressure, the pressure is 0.5-5 Torr and the temperature is 0-50 ℃; in the step of distillation under reduced pressure, the pressure is 0.02-5 Torr and the temperature is 100-190 ℃; The preparation method further comprises subjecting the double (acetylacetone) tin prepared in step (3) to reduced pressure rectification treatment; in the step of reduced pressure rectification treatment, the pressure is 0.02-5 Torr and the temperature is 100-190 ℃; the metal purity of the double (acetylacetone) tin after the reduced pressure rectification treatment is not less than 5N.

2. The production method according to claim 1, characterized by, In step (1), the acetylacetone alkali metal salt is selected from one or more of sodium acetylacetonate, potassium acetylacetonate and lithium acetylacetonate.

3. The preparation method according to claim 1, characterized in that, In step (1), the molar ratio of the acetylacetone alkali metal salt to acetylacetone is 1:1-3.

4. The method of claim 1, wherein, In step (1), the solvent is selected from one or more of toluene, n-hexane and diethyl ether.

5. The preparation method according to claim 1, characterized in that, In step (2), the stannous chloride is added to the reaction solution at-20-20 ℃; the molar ratio of the stannous chloride to acetylacetone is 1:2-5.

6. The method of claim 1, wherein, In step (2), the stirring reaction temperature is 0-30 ℃, and the stirring reaction time is not less than 3 h.

7. The preparation method according to claim 1, characterized in that, The inert atmosphere is nitrogen and / or argon.

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