A method for preparing high-purity palladium hexafluoroacetylacetonate

Abstract

The application provides a preparation method of high-purity palladium hexafluoroacetylacetone, comprising the following steps: step S1, adding a pH regulator, hexafluoroacetylacetone and water into a reactor to dissolve to obtain a dissolved solution, and adding a divalent palladium salt into water to dissolve to obtain a divalent palladium salt aqueous solution; step S2, introducing inert gas into the dissolved solution; step S3, adding an organic phase into the dissolved solution to form a microemulsion reaction system; step S4, adding the divalent palladium salt aqueous solution into a reactor in an ultrasonic generator in the microemulsion reaction system, and ultrasonic treatment to obtain a reaction solution; step S5, filtering and washing the reaction solution to neutral, and drying the reaction solution to obtain a crude product; step S6, purifying the crude product, rotary evaporation, and drying to obtain a primary purified product; step S7, recrystallizing the primary purified product, and filtering to obtain a crystal; and step S8, drying the crystal to obtain a product. The preparation method has the advantages of simple process, controllable condition, small pollution, high preparation efficiency of the palladium hexafluoroacetylacetone, and high purity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of palladium compounds, in particular to a preparation method of high-purity palladium hexafluoroacetylacetone. BACKGROUND

[0002] Palladium hexafluoroacetylacetone is an important palladium complex and reaction precursor. Due to the physical and chemical properties of the substance, such as easy sublimation, no chlorine element and easy solubility in organic solvents, it is often used to optimize the chemical vapor deposition alloying process of copper and simultaneously etch copper and deposit palladium, thereby being applied to the preparation of ultra-large scale integrated equipment, and also being an important homogeneous catalyst in the field of petroleum and chemical industry.

[0003] At present, the preparation technology of palladium hexafluoroacetylacetone is to mix hexafluoroacetylacetone with sodium hydroxide solution and stir to prepare sodium hexafluoroacetylacetone solution and then add Na2PdCl4 to prepare palladium hexafluoroacetylacetone. The preparation efficiency of this method is very low, and the yield is only about 42%, which causes a large amount of palladium to enter the waste liquid and increases the recovery cost. SUMMARY

[0004] The purpose of the present application is to overcome and supplement the deficiencies in the prior art, and to provide a preparation method of high-purity palladium hexafluoroacetylacetone. The present application overcomes the problem of low yield by increasing the organic phase and forming a microemulsion reaction system by ultrasonic method, thereby greatly improving the reaction efficiency.

[0005] The technical scheme adopted by the present application is:

[0006] A preparation method of high-purity palladium hexafluoroacetylacetone, comprising the following steps:

[0007] Step S1. Dissolve pH adjuster, hexafluoroacetylacetone and water in a reactor to obtain a dissolution solution, and dissolve divalent palladium salt in water to obtain a divalent palladium salt aqueous solution;

[0008] Step S2. Inert gas is introduced into the dissolution solution in step S1 to ensure the inert atmosphere of the reaction environment;

[0009] Step S3. An organic phase is added to the dissolution solution in step S2 to form a microemulsion reaction system;

[0010] Step S4. The microemulsion reaction system in step S3 is added to the reactor in the ultrasonic generator and kept at a constant temperature, then the divalent palladium salt aqueous solution is added dropwise to the microemulsion reaction system, ultrasonic is performed after the dropwise addition is completed, and the reaction liquid is obtained after the ultrasonic is completed;

[0011] Step S5. The reaction liquid is filtered, washed with water to neutral, and dried to obtain a crude product;

[0012] Step S6. Purify the crude product in step S5 by column chromatography, then rotary evaporate the solvent, dry, and obtain the primary purified product;

[0013] Step S7. Recrystallize the primary purified product in step S6 by recrystallization solvent, and filter to obtain the crystal;

[0014] Step S8. Dry the crystal in step S7, and obtain the product.

[0015] Preferably, the method for preparing high-purity palladium hexafluoroacetylacetonate, wherein: the pH regulator in step S1 is selected from one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate; the divalent palladium salt is selected from one of palladium dichloride, chloropalladite, potassium chloropalladite, and sodium chloropalladite; the mass ratio of the pH regulator to hexafluoroacetylacetone is 1-10:50; the mass ratio of hexafluoroacetylacetone to the divalent palladium salt is 1-100:20; and the mass ratio of water to the divalent palladium salt is 1-100:10.

[0016] Preferably, the method for preparing high-purity palladium hexafluoroacetylacetonate, wherein: the inert gas in step S2 is one or both of argon and nitrogen; and the bubbling speed of the inert gas into the dissolving solution is 1-2 bubbles / s.

[0017] Preferably, the method for preparing high-purity palladium hexafluoroacetylacetonate, wherein: the organic phase in step S3 is selected from one or more of toluene, benzene, n-hexane, n-heptane, and chloroform; and the mass ratio of the organic phase to the dissolving solution is 1:10-100.

[0018] Preferably, the method for preparing high-purity palladium hexafluoroacetylacetonate, wherein: the constant temperature in step S4 is 0-70°C; the ultrasonic frequency is 20-200 kHz; and the ultrasonic time is 1-300 min.

[0019] Preferably, the method for preparing high-purity palladium hexafluoroacetylacetonate, wherein: in step S5, the filter cake after filtering the reaction solution is washed with deionized water until the pH is 6-7; the drying method is low-temperature vacuum drying; the drying temperature is 20-70°C; and the drying time is 4-8 h.

[0020] Preferably, the method for preparing high-purity palladium hexafluoroacetylacetonate, wherein: in step S6, the organic phase for column chromatography is ethyl acetate and n-hexane; the volume ratio of ethyl acetate to n-hexane is 3:1-10:1; the particle size of the silica gel powder for column chromatography is 300-400 mesh; after the column chromatography is completed, the solvent is rotary evaporated; the drying method is low-temperature vacuum drying; the drying temperature is 20-70°C; and the drying time is 4-8 h.

[0021] Preferably, the preparation method of high-purity palladium hexafluoroacetylacetone, wherein: the recrystallization solvent in step S7 is selected from one of n-hexane, n-heptane, ethanol, propanol and methanol; the low-temperature refrigeration temperature of the recrystallization solvent is 0~-80℃.

[0022] Preferably, the preparation method of high-purity palladium hexafluoroacetylacetone, wherein: the drying method of step S8 is low-temperature vacuum drying, the drying temperature is 20~70℃, and the drying time is 4~8h.

[0023] Advantages of the present application:

[0024] (1) The preparation method of high-purity palladium hexafluoroacetylacetone has simple process, controllable conditions, small pollution, high preparation efficiency and high purity of palladium hexafluoroacetylacetone.

[0025] (2) The preparation method of high-purity palladium hexafluoroacetylacetone forms a microemulsion of oil-in-water structure with organic solvents and water, and forms countless micro-reaction systems through ultrasonic vibration. Palladium salt is dissolved in water, and hexafluoroacetylacetone is more easily dissolved in organic solvents. The reaction of the two in the oil-in-water microsystem increases the reaction activity and reaction area, thereby improving the reaction efficiency. DETAILED DESCRIPTION

[0026] The present application will be further described below in conjunction with specific examples.

[0027] Example 1

[0028] A preparation method of high-purity palladium hexafluoroacetylacetone, comprising the following steps:

[0029] Step S1. 2g of sodium hydroxide, 6g of hexafluoroacetylacetone and 35g of deionized water were added to a 250ml reactor for dissolution to obtain a dissolution solution, and 3g of K2PdCl4 was added to water for dissolution to obtain a potassium chloropalladite aqueous solution;

[0030] Step S2. Inert gas argon was introduced into the dissolution solution in step S1 to remove air in the solution by bubbling, and the bubbling speed of argon was about 1~2 bubbles / s to ensure the inert atmosphere of the reaction environment;

[0031] Step S3. 0.2g of toluene was added to the dissolution solution in step S2 to form a microemulsion reaction system;

[0032] Step S4. The microemulsion reaction system in step S3 was added to the reactor in the ultrasonic generator and kept at 30℃, then the potassium chloropalladite aqueous solution was added dropwise to the microemulsion reaction system, after the dropwise addition was completed, ultrasonic was performed, the ultrasonic frequency was 30kHz, the ultrasonic time was 60min, and the reaction liquid was obtained after ultrasonic was completed;

[0033] Step S5. The reaction solution is filtered, the filter cake produced by the filtration is washed with deionized water multiple times until the pH value is 6-7, and the filter cake is vacuum dried at 40°C for 8h to obtain a crude product;

[0034] Step S6. An organic solution with a volume ratio of ethyl acetate to n-hexane of 5:1 is configured, 300-400 mesh silica gel powder is selected, column chromatography is used to purify the crude product in step S5, and then the solvent is distilled off by rotary evaporation, dried, and a preliminarily purified product is obtained;

[0035] Step S7. The preliminarily purified product in step S6 is dissolved in n-hexane at 69°C, recrystallized at -10°C, and filtered to obtain a crystalline product;

[0036] Step S8. The crystalline product in step S7 is vacuum dried at 30°C for 8h to obtain a product, and the yield is 46%.

[0037] Example 2

[0038] A method for preparing high-purity palladium hexafluoroacetylacetone, comprising the following steps:

[0039] Step S1. 2g of sodium hydroxide, 6g of hexafluoroacetylacetone, and 35g of deionized water are added to a 250ml reactor to form a solution, and 3g of K2PdCl4 is added to water to form a potassium chloropalladite aqueous solution;

[0040] Step S2. Inert argon gas is introduced into the solution in step S1 to remove air in the solution by bubbling, and the bubbling speed of the argon gas is about 1-2 bubbles / s to ensure an inert atmosphere in the reaction environment;

[0041] Step S3. 0.8g of toluene is added to the solution in step S2 to form a microemulsion reaction system;

[0042] Step S4. The microemulsion reaction system in step S3 is added to a reactor in an ultrasonic generator and kept at a constant temperature of 45°C, and then the potassium chloropalladite aqueous solution is added dropwise to the microemulsion reaction system, and ultrasonic treatment is started, and after the dropwise addition is completed, ultrasonic treatment is continued, the ultrasonic frequency is 50kHz, the ultrasonic time is 120min, and after the ultrasonic treatment is completed, a reaction solution is obtained;

[0043] Step S5. The reaction solution is filtered, the filter cake produced by the filtration is washed with deionized water multiple times until the pH value is 6-7, and the filter cake is vacuum dried at 40°C for 8h to obtain a crude product;

[0044] Step S6. An organic solution with a volume ratio of ethyl acetate to n-hexane of 5:1 is configured, 300-400 mesh silica gel powder is selected, column chromatography is used to purify the crude product in step S5, and then the solvent is distilled off by rotary evaporation, dried, and a preliminarily purified product is obtained;

[0045] Step S7. The primary purified product of step S6 is dissolved by 69℃ n-hexane, recrystallized in -50℃ refrigerator, and the crystal is obtained by filtration;

[0046] Step S8. The crystal of step S7 is vacuum dried at 30℃ for 8h to obtain the product, and the yield is 64%.

[0047] Example 3

[0048] A method for preparing high-purity palladium hexafluoroacetylacetone, comprising the following steps:

[0049] Step S1. 20g of sodium hydroxide, 60g of hexafluoroacetylacetone, and 350g of deionized water are added to a 2500ml reactor to obtain a dissolved solution, and 30g of K2PdCl4 is dissolved in water to obtain a divalent palladium salt aqueous solution;

[0050] Step S2. Inert gas argon is introduced into the dissolved solution of step S1 to remove air in the solution by bubbling, and the bubbling speed of argon is about 1~2 bubbles / s to ensure the inert atmosphere of the reaction environment;

[0051] Step S3. 15g of toluene is added to the dissolved solution of step S2 to form a microemulsion reaction system;

[0052] Step S4. The microemulsion reaction system of step S3 is added to the reactor in the ultrasonic generator and kept at a constant temperature of 45℃, then the ultrasonic is started after adding the potassium chloropalladite aqueous solution into the microemulsion reaction system, and the ultrasonic is stopped after the addition is completed, the ultrasonic frequency is 50kHz, the ultrasonic time is 120min, and the reaction liquid is obtained after the ultrasonic is stopped;

[0053] Step S5. The reaction liquid is filtered, the filter cake produced by the filtration is washed with deionized water for multiple times until the pH value is 6~7, and the crude product is obtained by vacuum drying at 40℃ for 8h;

[0054] Step S6. An organic solution with a volume ratio of ethyl acetate to n-hexane of 5:1 is configured, 300~400 mesh silica gel powder is selected, and the crude product of step S5 is purified by column chromatography, then the solvent is distilled off by rotary evaporation, and the primary purified product is obtained after drying;

[0055] Step S7. The primary purified product of step S6 is dissolved by 69℃ n-hexane, recrystallized in -50℃ refrigerator, and the crystal is obtained by filtration;

[0056] Step S8. The crystal of step S7 is vacuum dried at 30℃ for 8h to obtain the product, and the yield is 64%.

[0057] Comparative Example 1

[0058] A method for preparing high-purity palladium hexafluoroacetylacetone, comprising the following steps:

[0059] Step S1. 2g of sodium hydroxide, 6g of hexafluoroacetylacetone, and 35g of deionized water are added to a 250ml reactor for dissolution to obtain a dissolution solution, and 3g of K2PdCl4 is dissolved in water to obtain a potassium chloropalladite aqueous solution;

[0060] Step S2. Inert gas argon is introduced into the dissolution solution in step S1 to remove air in the solution by bubbling, and the bubbling speed of the introduced argon is about 1-2 bubbles / s to ensure an inert atmosphere in the reaction environment;

[0061] Step S3. The dissolution solution in step S2 is added to a flask for constant temperature heating and placed in an ultrasonic generator, the constant temperature is 45℃, ultrasonic is started after adding the potassium chloropalladite aqueous solution, the ultrasonic frequency is 50kHz, and the ultrasonic time is 120min, and the reaction liquid is obtained after the ultrasonic is stopped;

[0062] Step S4. The reaction liquid is filtered, the filter cake generated by the filtration is washed with deionized water for multiple times until the pH value is 6-7, and the crude product is obtained by vacuum drying at 40℃ for 8h;

[0063] Step S6. An organic solution with a volume ratio of ethyl acetate to n-hexane of 5:1 is configured, 300-400 mesh silica gel powder is selected, and column chromatography is used to purify the crude product in step S5, and then the solvent is distilled off by rotary evaporation, dried, and the preliminary purified product is obtained;

[0064] Step S7. The preliminary purified product in step S6 is dissolved in n-hexane at 69℃, and recrystallized by cold storage at-50℃, and the crystal is obtained by filtration;

[0065] Step S8. The crystal in step S7 is vacuum dried at 30℃ for 8h to obtain the product, and the yield is 38%.

[0066] Comparative Example 2

[0067] A method for preparing high-purity palladium hexafluoroacetylacetone, comprising the following steps:

[0068] Step S1. 2g of sodium hydroxide, 6g of hexafluoroacetylacetone, and 35g of deionized water are added to a 250ml reactor for dissolution to obtain a dissolution solution, and 3g of K2PdCl4 is dissolved in water to obtain a potassium chloropalladite aqueous solution;

[0069] Step S2. Inert gas argon is introduced into the dissolution solution in step S1 to remove air in the solution by bubbling, and the bubbling speed of the introduced argon is about 1-2 bubbles / s to ensure an inert atmosphere in the reaction environment;

[0070] Step S3. 0.8 g of toluene was added to the solution of step S2 to form a microemulsion reaction system;

[0071] Step S4. The microemulsion reaction system of step S3 was added to a flask for constant temperature heating, the constant temperature was 45°C, and the potassium chloropalladite aqueous solution was added dropwise, and the magnetic stirring was performed for 120 min. After the stirring was completed, a reaction solution was obtained;

[0072] Step S5. The reaction solution was filtered, the filter cake generated in the filtration was washed with deionized water for multiple times until the pH value was 6-7, and the filter cake was vacuum dried at 40°C for 8 h to obtain a crude product;

[0073] Step S6. An organic solution of ethyl acetate and n-hexane with a volume ratio of 5:1 was configured, 300-400 mesh silica gel powder was selected, and the crude product of step S5 was purified by column chromatography. Then, the solvent was distilled off by rotary evaporation, and the product was dried to obtain a preliminary purified product;

[0074] Step S7. The preliminary purified product of step S6 was dissolved in n-hexane at 69°C, and recrystallized at -50°C. The crystal was obtained by filtration.

[0075] Step S8. The crystal of step S7 was vacuum dried at 30°C for 8 h to obtain a product, and the yield was 43%.

[0076] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the examples, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. A method for preparing high purity palladium hexafluoroacetylacetonate, characterized by: The method comprises the following steps: Step S1. A pH regulator, hexafluoroacetylacetone and water are added into a reactor to be dissolved to obtain a dissolved solution, and a divalent palladium salt is dissolved in water to obtain a divalent palladium salt aqueous solution; Step S2. Inert gas is introduced into the dissolved solution in step S1 to ensure inert atmosphere of the reaction environment; Step S3. The dissolved solution in step S2 is added into an organic phase to form a microemulsion reaction system; Step S4. The microemulsion reaction system in step S3 is added into a reactor in an ultrasonic generator and kept at constant temperature, then the divalent palladium salt aqueous solution is added dropwise into the microemulsion reaction system, ultrasonic treatment is performed after the dropwise addition is completed, and a reaction solution is obtained after the ultrasonic treatment; Step S5. The reaction solution is filtered, washed with water until neutral, and dried to obtain a crude product; Step S6. The crude product in step S5 is purified by column chromatography, then the solvent is distilled off by rotary evaporation, and dried to obtain a preliminary purified product; Step S7. The preliminary purified product in step S6 is recrystallized by using a recrystallization solvent, and a crystal is obtained by filtration; Step S8. The crystal in step S7 is dried to obtain a product; The pH regulator in step S1 is selected from one or more of sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate; the divalent palladium salt is selected from one of palladium dichloride, chloropalladic acid, potassium chloropalladic acid and sodium chloropalladic acid; the mass ratio of the pH regulator to hexafluoroacetylacetone is 1-10:50, the mass ratio of hexafluoroacetylacetone to the divalent palladium salt is 1-100:20, and the mass ratio of water to the divalent palladium salt is 1-100:10; The bubbling speed of the inert gas introduced into the dissolved solution in step S2 is 1-2 bubbles / s; The constant temperature in step S4 is 30-70℃, the ultrasonic frequency is 20-200 kHz, and the ultrasonic time is 1-300 min; The organic phase in step S3 is selected from one or more of toluene, benzene, n-hexane, n-heptane and chloroform, and the mass ratio of the organic phase to the dissolved solution is 1:10-100.

2. The method for preparing high-purity palladium hexafluoroacetylacetonate according to claim 1, characterized in that: The inert gas in step S2 is one or both of argon and nitrogen.

3. The method for preparing high-purity palladium hexafluoroacetylacetonate according to claim 1, characterized in that: The filter cake after the reaction solution in step S5 is filtered is washed with deionized water until the pH is 6-7, the drying mode is low-temperature vacuum drying, the drying temperature is 20-70℃, and the drying time is 4-8 h.

4. The method for preparing high-purity palladium hexafluoroacetylacetonate according to claim 1, characterized in that: The organic phase for column chromatography in step S6 is ethyl acetate and n-hexane, the volume ratio of ethyl acetate to n-hexane is 3:1-10:1, the particle size of the silica gel powder for column chromatography is 300-400 mesh, the rotary evaporation is performed after the column chromatography is completed, the drying mode is low-temperature vacuum drying, the drying temperature is 20-70℃, and the drying time is 4-8 h.

5. The method for preparing high-purity palladium hexafluoroacetylacetonate according to claim 1, characterized in that: The recrystallization solvent in step S7 is selected from one of n-hexane, n-heptane, ethanol, propanol and methanol; and the low-temperature refrigeration temperature of the recrystallization solvent is 0--80℃.

6. The method for preparing high-purity palladium hexafluoroacetylacetonate according to claim 1, characterized in that: The drying mode in step S8 is medium-low temperature vacuum drying, the drying temperature is 20-70℃, and the drying time is 4-8 h.