Method for preparing deuterium acetone through exchange reaction
The method of preparing deuterium acetone through exchange reactions solves the problems of many consumables and complex processes in the prior art, and achieves efficient and low-cost production of deuterium acetone, with high yield and purity reaching high standards.
Patent Information
- Application Number
- CN202510655327.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-21
- Publication Date
- 2025-08-26
AI Technical Summary
In the prior art, there are many consumables for production of deuterated acetone and complex processes, which leads to high costs and difficult operation.
The method of preparing deuterium acetone through an exchange reaction includes steps such as removing acetone from water, cooling and reflux with heavy water and catalyst, fractionation, etc., using potassium carbonate as a catalyst, vacuuming and insulating using a reflux condenser jacket, multiple hydrogen-deuterium exchange reactions and separating the product in the fractionator.
It effectively reduces product dilution, saves equipment costs, improves the deuterated utilization rate and simplicity of product separation, and reaches 91-92% yield and purity, and the deuterated rate is >99.8%.
Smart Images
Figure CN120535401A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of chemical synthesis, and in particular to a method for preparing deuterated acetone through an exchange reaction. Background Art
[0002] Deuterated acetone is mainly used as a solvent in nuclear magnetic resonance spectroscopy because it produces relatively little signal interference in nuclear magnetic resonance detection. It can dissolve many organic compounds well and is widely used in compound analysis and detection in fields such as organic chemistry and medicinal chemistry.
[0003] A method for producing deuterated acetone using a distillation column currently exists. This involves three steps: an exchange reaction between acetone, heavy water, and potassium carbonate, followed by distillation to produce a crude deuterated acetone, and then dehydration of the crude product. This process requires the use of a dehydration column and nitrogen blanketing at each step, resulting in a high number of consumables and a complex process. Summary of the Invention
[0004] The object of the present invention is to provide a method for preparing deuterated acetone by an exchange reaction, so as to solve the technical problems in the prior art of producing deuterated acetone, such as a large number of consumable materials and a complicated process.
[0005] The present invention discloses a method for preparing deuterated acetone by an exchange reaction, comprising the following steps:
[0006] S1. Acetone dehydration;
[0007] S2. After removing water, acetone and heavy water, deuterium oxide, and catalyst are added and cooled and refluxed;
[0008] S3. Perform fractionation and collect the middle fraction;
[0009] S4. Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, cool and reflux again, and then perform fractional distillation to collect the middle fraction.
[0010] The reaction that occurs is: CH3COCH3+3D2O=CD3COCD3+3H2O.
[0011] Furthermore, the specific steps of removing water from acetone in step S1 are: adding acetone to the reactor, opening cooling water for the top condenser, heating the reactor, and insulating and keeping it warm after the reactor reaches the boiling point.
[0012] Furthermore, the thermal insulation is achieved by evacuating the jacket of the reflux condenser for 15-20 minutes.
[0013] Furthermore, after removing water, acetone is collected by fractional distillation.
[0014] Furthermore, after removing water, acetone was added at a rate of 40-50 drops per minute and the fraction between 55±0.5°C was collected.
[0015] Furthermore, in step S2, the materials are added according to a volume ratio of acetone:deuterium oxide = 1:1-1.5, and the catalyst is 0.5-1% of the weight of deuterium oxide.
[0016] Furthermore, the cooling and reflux time in step S2 is 4 to 5 hours.
[0017] Furthermore, the reflux ratio in the cooling reflux in step S2 is 1:1.
[0018] Furthermore, the distillation temperature in step S3 is 55±1°C.
[0019] Furthermore, the temperature of the fractionation is kept warm by evacuating the jacket.
[0020] Furthermore, the fractionated tail gas is recovered by liquid nitrogen cooling and then discharged through a drying tower.
[0021] Furthermore, the catalyst is potassium carbonate or sodium carbonate.
[0022] Compared with the prior art, the present invention has the following beneficial effects:
[0023] 1. The raw material acetone is treated to remove water before use, which can effectively avoid diluting the concentration of heavy water when it comes into contact with heavy water, thereby reducing the deuteration degree of the product;
[0024] 2. The present invention uses the reflux condenser jacket to evacuate for heat preservation, effectively saving equipment costs;
[0025] 3. Based on potassium carbonate as a catalyst, the reagent raw material acetone and heavy water undergo multiple hydrogen-deuterium exchange reactions and are separated in a fractionator to obtain the product. This method has the advantages of good operability and stability, high deuterium utilization rate, and simple product separation. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only represent some embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.
[0027] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.
[0029] Example 1
[0030] This embodiment discloses a method for preparing deuterated acetone by an exchange reaction, such as Figure 1 As shown, the following steps are included:
[0031] Step 1: Install the cleaned and dried equipment, add acetone to 2 / 3 of the total volume of the distillation flask, turn on the cooling water of the distillation condenser and the cooling water of the top condenser, and start heating the tower kettle.
[0032] Step 2: Evacuate the jacket of the reflux condenser for 15-20 minutes to achieve thermal insulation.
[0033] Step 3: Adjust the temperature and control the distillation rate to 40-50 drops per minute. Collect the fraction between 55±0.5℃, which is the acetone after dehydration.
[0034] Step 4: Add the acetone after dehydration into the tower according to the ratio of acetone to deuterium oxide = 1:1.1 (volume ratio) and potassium carbonate to 0.5% of the deuterium oxide amount, and cool and reflux for 4 hours.
[0035] Step 5: Adjust the cooling water of the top condenser to maintain a reflux ratio of 1:1.
[0036] Step 6: Open the cooling water of the fractionation condenser to condense the evaporated deuterated acetone as completely as possible into the collection bottle. The tail gas is recovered by liquid nitrogen cooling hydrazine and then discharged through the drying tower.
[0037] Step 7: Turn on the vacuum pump for 15-20 minutes to evacuate the jacket of the reflux condenser to keep it warm for fractionation.
[0038] Step 8: Control the distillation temperature at 55±1°C and collect the middle fraction.
[0039] Step 9: Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, and repeat step 4.
[0040] Step 10: When the estimated dilute deuterium oxide concentration reaches 99.65 atomic % D, perform a dilute deuterium oxide analysis. When the dilute deuterium oxide concentration reaches 99.70 atomic % D, perform fractional distillation. Collect the intermediate fraction as the product. The yield is 91%, the deuterium substitution rate is >99.8%, and the purity is >99%.
[0041] Example 2
[0042] Step 1: Install the cleaned and dried equipment, add acetone to 2 / 3 of the total volume of the distillation flask, turn on the cooling water of the distillation condenser and the cooling water of the top condenser, and start heating the tower kettle.
[0043] Step 2: Evacuate the jacket of the reflux condenser for 15-20 minutes to achieve thermal insulation.
[0044] Step 3: Adjust the temperature and control the distillation rate to 40-50 drops per minute. Collect the fraction between 55±0.5℃, which is the acetone after dehydration.
[0045] Step 4: Add the acetone after dehydration into the tower according to the ratio of acetone to deuterium oxide = 1:1.3 (volume ratio) and potassium carbonate to 0.8% of the deuterium oxide amount, and cool and reflux for 3 hours.
[0046] Step 5: Adjust the cooling water of the top condenser to maintain a reflux ratio of 1:1.
[0047] Step 6: Open the cooling water of the fractionation condenser to condense the evaporated deuterated acetone as completely as possible into the collection bottle. The tail gas is recovered by liquid nitrogen cooling hydrazine and then discharged through the drying tower.
[0048] Step 7: Turn on the vacuum pump for 15-20 minutes to evacuate the jacket of the reflux condenser to keep it warm for fractionation.
[0049] Step 8: Control the distillation temperature at 55±1°C and collect the middle fraction
[0050] Step 9: Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, and repeat Step 4. The collected middle fraction is deuterated acetone. The yield is 92%, the deuteration rate is >99.8%, and the purity is >99%.
[0051] Comparative Example 1
[0052] Step 1: Install the cleaned and dried equipment, add acetone to 2 / 3 of the total volume of the distillation flask, turn on the cooling water of the distillation condenser and the cooling water of the top condenser, and start heating the tower kettle.
[0053] Step 2: Evacuate the jacket of the reflux condenser for 15-20 minutes to achieve thermal insulation.
[0054] Step 3: Adjust the cooling water volume of the overhead condenser and the voltage of the electric heating jacket to control the distillation rate at 40-50 drops per minute. Collect the fraction between 55±0.5°C, which is the acetone after dehydration.
[0055] Step 4: Add the dehydrated acetone to the reactor at a volume ratio of acetone to deuterium oxide of 1:1.8 and potassium carbonate to 0.5% of the deuterium oxide content, and cool and reflux for 4 hours.
[0056] Step 5: Adjust the cooling water of the top condenser to maintain a reflux ratio of 1:1.
[0057] Step 6: Open the cooling water of the fractionation condenser to condense the evaporated deuterated acetone as completely as possible into the collection bottle. The tail gas is recovered by liquid nitrogen cooling hydrazine and then discharged through the drying tower.
[0058] Step 7: Turn on the vacuum pump for 15-20 minutes to evacuate the jacket of the reflux condenser to keep it warm for fractionation.
[0059] Step 8: Control the distillation temperature at 55±1°C and collect the middle fraction.
[0060] Step 9: Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, and repeat Step 4. The collected middle fraction is deuterated acetone. The yield is 80%, the deuteration rate is >99.8%, and the purity is >99%.
[0061] Comparative Example 2
[0062] Step 1: Install the cleaned and dried equipment, add acetone to 2 / 3 of the total volume of the distillation flask, turn on the cooling water of the distillation condenser and the cooling water of the top condenser, and start heating the tower kettle.
[0063] Step 2: Evacuate the jacket of the reflux condenser for 15-20 minutes to achieve thermal insulation.
[0064] Step 3: Adjust the cooling water volume of the overhead condenser and the voltage of the electric heating jacket to control the distillation rate at 40-50 drops per minute. Collect the fraction between 55±0.5°C, which is the acetone after dehydration.
[0065] Step 4: Add the dehydrated acetone to the reactor at a volume ratio of acetone to deuterium oxide of 1:0.5 and potassium carbonate to 0.5% of the deuterium oxide content, and cool and reflux for 4 hours.
[0066] Step 5: Adjust the cooling water of the top condenser to maintain a reflux ratio of 1:1.
[0067] Step 6: Open the cooling water of the fractionation condenser to condense the evaporated deuterated acetone as completely as possible into the collection bottle. The tail gas is recovered by liquid nitrogen cooling hydrazine and then discharged through the drying tower.
[0068] Step 7: Turn on the vacuum pump for 15-20 minutes to evacuate the jacket of the reflux condenser to keep it warm for fractionation.
[0069] Step 8: Control the distillation temperature at 55±1°C and collect the middle fraction.
[0070] Step 9: Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, and repeat Step 4. The collected middle fraction is deuterated acetone. The yield is 85%, the deuteration rate is <99.5%, and the purity is >99%.
[0071] Comparative Example 3
[0072] Step 1: Add acetone to deuterium oxide at a ratio of 1:1.1 (volume ratio) and potassium carbonate at 0.5% of the amount of deuterium oxide into the reactor, and cool and reflux for 4 hours.
[0073] Step 2: Adjust the cooling water of the top condenser to maintain a reflux ratio of 1:1.
[0074] Step 3: Open the cooling water of the fractionation condenser to condense the evaporated deuterated acetone as completely as possible into the collection bottle. The tail gas is recovered by liquid nitrogen cooling hydrazine and then discharged through the drying tower.
[0075] Step 4: Turn on the vacuum pump for 15-20 minutes to evacuate the jacket of the reflux condenser to keep it warm for fractionation.
[0076] Step 5: Control the distillation temperature at 55±1°C and collect the middle fraction.
[0077] Step 6: Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, and repeat Step 1. The collected middle fraction is deuterated acetone. The yield is 88%, the deuteration rate is <99.5%, and the purity is <98%.
[0078] Comparative Example 4
[0079] Step 1: Install the cleaned and dried equipment, add acetone to 2 / 3 of the total volume of the distillation flask, turn on the cooling water of the distillation condenser and the cooling water of the top condenser, and start heating the tower kettle.
[0080] Step 2: Evacuate the jacket of the reflux condenser for 15-20 minutes to achieve thermal insulation.
[0081] Step 3: Adjust the temperature and control the distillation rate to 40-50 drops per minute. Collect the fraction between 55±0.5℃, which is the acetone after dehydration.
[0082] Step 4: Add the acetone after dehydration into the kettle according to the ratio of acetone to deuterium oxide = 1:1.1 (volume ratio), and cool and reflux for 4 hours.
[0083] Step 5: Adjust the cooling water of the top condenser to maintain a reflux ratio of 1:1.
[0084] Step 6: Open the cooling water of the fractionation condenser to condense the evaporated deuterated acetone as completely as possible into the collection bottle. The tail gas is recovered by liquid nitrogen cooling hydrazine and then discharged through the drying tower.
[0085] Step 7: Turn on the vacuum pump for 15-20 minutes to evacuate the jacket of the reflux condenser to keep it warm for fractionation.
[0086] Step 8: Control the distillation temperature at 55±1°C and collect the middle fraction.
[0087] Step 9: Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, and repeat step 4.
[0088] Step 10: When the dilute deuterium oxide concentration reaches an estimated 99.65 atomic % D, a dilute deuterium oxide analysis should be performed. When the dilute deuterium oxide concentration reaches 99.70 atomic % D, fractional distillation is performed. The intermediate fraction is the product. The yield is 60%, the deuterium substitution rate is <99.5%, and the purity is >99%.
[0089] It can be seen from Examples 1-2 and Comparative Examples 1-2 that the optimal volume ratio is acetone: deuterium oxide = 1:1-1.5. A large deuterium oxide input ratio affects the yield, while a low deuterium oxide input ratio affects the deuterium substitution rate.
[0090] In Comparative Example 3, the deuterated acetone deuteration rate was less than 99.5% and the purity was less than 98% due to the lack of acetone water removal step, which was significantly lower than the effect achieved by the technical solution of the present invention.
[0091] In Comparative Example 4, since no catalyst was added, the yield of deuterated acetone was 60%, and the deuteration rate was <99.5%, which was significantly lower than the effect that could be achieved by the technical solution of the present invention.
[0092] The above are the implementation methods listed in this embodiment, but this embodiment is not limited to the above optional implementation methods. Those skilled in the art can arbitrarily combine the above methods to obtain other various implementation methods. Anyone can derive other various forms of implementation methods based on the inspiration of this embodiment. The above specific implementation methods should not be understood as limiting the scope of protection of this embodiment. The scope of protection of this embodiment shall be based on the definition in the claims, and the description can be used to interpret the claims.
Claims
1. A method for preparing deuterated acetone by an exchange reaction, characterized in that: The following steps are involved: S1. Acetone dehydration; S2. After removing water, acetone and heavy water, deuterium oxide, and catalyst are added and cooled and refluxed; S3. Perform fractionation and collect the middle fraction; S4. Based on the collected middle fraction, calculate the weight of heavy water and deuterium oxide to be added again, cool and reflux again, and then perform fractional distillation to collect the middle fraction.
2. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: The specific steps of removing water from acetone in step S1 are: adding acetone to the reactor, opening cooling water for the top condenser, heating the reactor, and insulating and keeping it warm after the reactor reaches the boiling point.
3. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: After removing water, acetone was collected by fractional distillation.
4. The method for preparing deuterated acetone by an exchange reaction according to claim 3, wherein: After removing water, acetone was collected at a rate of 40-50 drops per minute and the fraction between 55±0.5℃ was collected.
5. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: In step S2, the materials are added according to a volume ratio of acetone to deuterium oxide of 1:0.9-1.5, and the catalyst is 0.5-1% of the weight of deuterium oxide.
6. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: The cooling and reflux time in step S2 is 4 to 5 hours.
7. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: The reflux ratio in the cooling reflux in step S2 is 1:
1.
8. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: The fractionation temperature in step S3 is 55±1°C.
9. The method for preparing deuterated acetone by an exchange reaction according to claim 1, wherein: The temperature of the fractionation is kept warm by evacuating the jacket.
10. The method for preparing deuterated acetone by exchange reaction according to claim 1, wherein: The catalyst is potassium carbonate or sodium carbonate.