A method and apparatus for preparing n-(trifluoromethanesulfonyl)trifluoroacetamide

Abstract

The application belongs to the technical field of N-(trifluoromethylsulfonyl) trifluoroacetamide preparation, and particularly relates to a method and device for preparing N-(trifluoromethylsulfonyl) trifluoroacetamide. The application generates N-(trifluoromethylsulfonyl) trifluoroacetamide by reacting trifluoroacetamide with trifluoromethylsulfonyl fluoride, mixes raw materials into acetonitrile solvent, introduces trifluoromethylsulfonyl fluoride for reaction, performs solid-liquid separation and drying. The molar ratio of raw materials, reaction temperature, pressure and drying conditions are controlled. The device is sequentially connected with each component to form a closed loop, the reaction kettle is provided with a frame type stirrer and a circulating water jacket, the single-cone dryer is provided with a screw stirrer and a heat conduction oil jacket, and acetonitrile solvent can be recycled, so that the method is adapted to realize efficient production.

Description

Technical Field

[0001] This application belongs to the field of N-(trifluoromethanesulfonyl)trifluoroacetamide preparation technology, specifically relating to a method and apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide. Background Technology

[0002] N-(trifluoromethanesulfonyl)trifluoroacetamide plays a key role in many fields such as electrolyte use, organic synthesis, catalysis, medicinal chemistry and materials science due to its unique chemical properties, and its production and application have become a research hotspot.

[0003] Methods for preparing N-(trifluoromethanesulfonyl)trifluoroacetamides are known as follows.

[0004] A method for preparing a thiotrifluoroacetamide compound is disclosed in invention patent CN109796387B, comprising the following steps: using (E)-N,1-diphenylimine as a substrate, adding an equivalent amount of elemental sulfur and 1.5 equivalents of 1,1,1-trifluorotrichloroethane to the substrate, and adding a catalyst, ligand, additive, base, and distilled water in a reaction solvent, stirring for 4 hours at 120°C and atmospheric pressure; after the reaction is completed, the reaction solution is filtered to obtain a filtrate; the filtrate is concentrated and the solvent is removed using a rotary evaporator to obtain a residue, which is then subjected to silica gel column chromatography and eluted with an eluent, and the eluent is collected according to the actual gradient; the eluents containing the product are combined, the combined eluent is concentrated to remove the solvent, and finally dried under vacuum to obtain the target product. However, this reaction requires a high temperature of 120°C for 4 hours. This high temperature condition not only increases energy consumption but also places higher demands on the material, sealing, and heat transfer control of the reaction vessel in industrial production, bringing potential safety risks. Furthermore, the subsequent processing steps after the reaction are complex and extremely unsuitable for large-scale industrial production.

[0005] Patent CN110041235B discloses an N-phenyl-N-p-toluenesulfonyltrifluoroacetamide and its applications. Using N-phenyl-N-p-toluenesulfonyltrifluoroacetamide as a trifluoroacetylation reagent, it reacts with arylboronic acid derivatives in an anhydrous organic solvent under the action of a metal catalyst, ligands, and a base, efficiently and selectively converting them into trifluoroacetophenone compounds. The synthetic method for trifluoroacetophenone compounds described in this application involves fewer reaction steps, uses stable, easily stored, inexpensive, and readily available NTFTS as the trifluoroacetyl source, is environmentally friendly, has mild reaction conditions, and is easy to operate. However, the reaction is relatively complex and difficult to scale up for industrial production.

[0006] In summary, there is an urgent need to develop a method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide that is efficient, economical, easy to operate, environmentally friendly, and easy to scale up industrially, in order to meet its growing application needs in various high-tech fields. Summary of the Invention

[0007] Regarding the preparation of N-(trifluoromethanesulfonic acid)trifluoroacetamide, this application proposes a method and apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide that is efficient, economical, easy to operate, environmentally friendly, and easy to scale up industrially.

[0008] On one hand, this application provides a method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, comprising the following steps: Step S1. In the solvent acetonitrile, trifluoroacetamide and potassium fluoride are mixed to form a reaction mixture; Step S2. Trifluoromethanesulfonyl fluoride is introduced into the reaction mixture to react and generate a reaction product containing N-(trifluoromethanesulfonyl)trifluoroacetamide; The reaction formula is: CF3SO2F+CF3CON(CH3)2→CF3CON(SO2CF3)CH3+HF Step S3. Perform solid-liquid separation on the reaction product to obtain a liquid phase containing N-(trifluoromethanesulfonyl)trifluoroacetamide; and dry the liquid phase to obtain the target product N-(trifluoromethanesulfonyl)trifluoroacetamide.

[0009] Preferably, the molar ratio of trifluoromethanesulfonyl fluoride to trifluoroacetamide is 1:(0.9-1.0).

[0010] Preferably, the molar ratio of potassium fluoride to trifluoroacetamide is (1.2-1.8):1.

[0011] Preferably, in step S1, the molar ratio of solvent acetonitrile to trifluoroacetamide is (5-7):1.

[0012] Preferably, the reaction temperature in step S2 is -10°C to 40°C, and the reaction pressure is atmospheric pressure to 0.2 MPa.

[0013] Preferably, the drying process in step S3 involves a temperature ≤160℃, a pressure ≤-0.09MPa, and a time of 12 hours.

[0014] On the other hand, this application provides an apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, the apparatus comprising: a trifluoromethanesulfonyl fluoride buffer tank, a reaction vessel, a scraped centrifuge, a solution buffer tank, a single cone dryer, a condenser, a solvent buffer tank, a metering tank, a trifluoroacetamide feeder, and a potassium fluoride feeder; The trifluoromethanesulfonyl fluoride buffer tank is connected to the reaction vessel and is used to supply trifluoromethanesulfonyl fluoride to the reaction vessel; Both the trifluoroacetamide feeder and the potassium fluoride feeder are connected to the reactor and are used to add trifluoroacetamide and potassium fluoride to the reactor. The bottom of the reactor is connected to a scraped centrifuge, which is used to transport the reaction materials to the scraped centrifuge for solid-liquid separation. The scraper centrifuge is connected to a solution buffer tank, and the separated liquid phase material enters the solution buffer tank. The solution buffer tank is connected to the single cone dryer and is used to transport liquid phase materials to the single cone dryer; One end of the condenser is connected to a single cone dryer, and the other end is connected to a solvent buffer tank for condensing and recovering acetonitrile solvent; The metering vessel is connected at one end to a solvent buffer tank and at the other end to a reaction vessel, and is used to measure the amount of solvent added to the reaction vessel.

[0015] Preferably, the reactor is equipped with a frame-type agitator inside and a jacket outside, with circulating water flowing through the jacket for cooling during the reaction process; the single-cone dryer is equipped with a ribbon agitator inside and a jacket outside, with heat transfer oil flowing through the jacket for providing a heat source during the drying process; and a shut-off valve two is installed at the bottom of the reactor for controlling the conveying of the reaction material to the scraper centrifuge.

[0016] Preferably, the trifluoromethanesulfonyl fluoride buffer tank, reaction vessel, and single-cone dryer are made of 316L stainless steel.

[0017] This application has several beneficial effects, as follows: This application demonstrates that the direct reaction of trifluoroacetamide with trifluoromethanesulfonyl fluoride to produce N-(trifluoromethanesulfonyl)trifluoroacetamide fundamentally simplifies the production process, shortens the reaction cycle, and provides support for the industrial-scale production of this product. The reaction itself exhibits extremely high product selectivity; the reaction between trifluoroacetamide and trifluoromethanesulfonyl fluoride is highly targeted, significantly reducing side reactions and improving reaction selectivity and feedstock conversion rate.

[0018] Adding potassium fluoride during the reaction process not only efficiently absorbs the hydrogen fluoride generated in the reaction, effectively eliminating the inhibitory effect of hydrogen fluoride on the reaction and promoting the reaction to proceed completely in the forward direction, thus improving the raw material conversion rate, but also prevents hydrogen fluoride from corroding the equipment. It forms a synergistic protection with the 316L stainless steel material used in the trifluoromethanesulfonyl fluoride buffer tank, reaction vessel, and single cone dryer in the unit, further extending the service life of the equipment and reducing equipment maintenance costs and the risk of downtime due to failure.

[0019] Choosing acetonitrile as a solvent not only enables efficient separation of products and impurities, but also allows for recycling through a recovery system consisting of a condenser and a solvent buffer tank, significantly reducing solvent consumption and raw material costs. Furthermore, the good compatibility of acetonitrile with the reaction system improves the uniformity of material mixing and promotes a complete reaction. At the same time, its volatility makes it suitable for the vacuum drying process of a single-cone dryer, allowing for rapid removal at lower temperatures, reducing solvent residue in the product, and improving the purity of the target product.

[0020] The unit is tightly connected to various valves via pipelines to form a closed-loop industrial production process. Combined with a trifluoroacetamide feeder, it achieves closed-loop transport of solid raw materials, effectively preventing leakage of fluorine-containing materials and reducing material loss during transport, further optimizing raw material utilization. The integrated automated control components, including flow meters, regulating valves, shut-off valves, and metering tanks, not only simplify operation and facilitate monitoring and maintenance, but also control the feeding ratio of each raw material, reaction temperature, pressure, and solvent recovery flow rate, ensuring consistency of process parameters across production batches and providing a reliable guarantee for large-scale continuous production.

[0021] The reactor employs a frame-type stirring structure, enabling thorough contact and mixing of gas, liquid, and solid phases. This avoids the formation of byproducts due to incomplete local reactions, thereby improving reaction efficiency and product selectivity. The entire process, from raw material feeding, reaction control, solid-liquid separation to drying, purification, and solvent recovery, forms a closed loop, eliminating the need for additional complex separation equipment. Furthermore, solvent recycling and closed-loop production reduce emissions of organic wastewater and exhaust gases. Attached Figure Description

[0022] Appendix Figure 1 This is a schematic diagram of the apparatus used to prepare N-(trifluoromethanesulfonyl)trifluoroacetamide according to this application.

[0023] Explanation of reference numerals in the attached diagram: 1. Trifluoromethanesulfonyl fluoride buffer tank; 2. Reactor; 3. Scraped centrifuge; 4. Solution buffer tank; 5. Single cone dryer; 6. Condenser; 7. Solvent buffer tank; 8. Metering tank; 9. Trifluoroacetamide feeder; 10. Flow meter; 11. Control valve; 12. Shut-off valve one; 13. Shut-off valve two; 14. Shut-off valve three; 15. Shut-off valve four; 16. Shut-off valve five; 17. Shut-off valve six; 18. Shut-off valve seven; 19. Shut-off valve eight; 20. Shut-off valve nine; 21. Shut-off valve ten; 22. Potassium fluoride feeder. Detailed Implementation

[0024] To further illustrate the technical means and effects adopted by this application in order to achieve the intended purpose of the invention, the following detailed description of the specific implementation methods, structures, features and effects of this application is provided in conjunction with the accompanying drawings and preferred embodiments.

[0025] This embodiment provides an apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, the apparatus comprising: a trifluoromethanesulfonyl fluoride buffer tank 1, a reaction vessel 2, a scraped centrifuge 3, a solution buffer tank 4, a single cone dryer 5, a condenser 6, a solvent buffer tank 7, a metering tank 8, a trifluoroacetamide feeder 9, and a potassium fluoride feeder 22. The trifluoromethanesulfonyl fluoride buffer tank 1 is connected to the reaction vessel 2 and is used to supply trifluoromethanesulfonyl fluoride to the reaction vessel 2; Both the trifluoroacetamide feeder 9 and the potassium fluoride feeder 22 are connected to the reactor 2 and are used to add trifluoroacetamide and potassium fluoride to the reactor 2. A shut-off valve 12 is installed on the pipeline connecting the trifluoroacetamide feeder 9 and the potassium fluoride feeder 22 in parallel to the reactor 2 to control the feeding of trifluoroacetamide and potassium fluoride. The bottom of the reaction vessel 2 is connected to the scraped centrifuge 3, which is used to transport the reaction materials to the scraped centrifuge 3 for solid-liquid separation; the scraped centrifuge 3 is connected to the solution buffer tank 4, and the separated liquid phase material enters the solution buffer tank 4; the bottom of the scraped centrifuge 3 is equipped with a shut-off valve 14, which is used to discharge the potassium fluoride solid waste after solid-liquid separation; a shut-off valve 15 is installed on the pipeline between the scraped centrifuge 3 and the solution buffer tank 4, which is used to control the on / off of the transport of the liquid phase material; The solution buffer tank 4 is connected to the single cone dryer 5 and is used to transport liquid phase material to the single cone dryer 5; a shut-off valve 16 is installed on the pipeline between the solution buffer tank 4 and the single cone dryer 5 to control the on / off supply of liquid phase material to the single cone dryer 5. One end of the condenser 6 is connected to the single cone dryer 5, and the other end is connected to the solvent buffer tank 7, for condensing and recovering acetonitrile solvent; a shut-off valve 7 18 is installed on the pipeline between the single cone dryer 5 and the condenser 6 to control the supply and disconnection of acetonitrile vapor to the condenser 6. One end of the metering tank 8 is connected to the solvent buffer tank 7, and the other end is connected to the reaction vessel 2, and is used to measure the amount of solvent added to the reaction vessel 2; a shut-off valve 20 is installed on the pipeline between the solvent buffer tank 7 and the metering tank 8, which is used to control the supply and disconnection of acetonitrile solvent to the metering tank 8. A shut-off valve 21 is installed on the pipeline between the metering tank 8 and the reaction vessel 2 to control the flow of metered acetonitrile solvent to the reaction vessel 2.

[0026] The reactor 2 is equipped with a frame-type stirrer inside and a jacket outside. The jacket is circulated with water for cooling the reaction process. The single cone dryer 5 is equipped with a spiral agitator inside and a jacket outside. The jacket is circulated with heat transfer oil to provide a heat source for the drying process. The bottom of the single cone dryer 5 is equipped with a shut-off valve 17 to discharge the dried target product N-(trifluoromethanesulfonyl)trifluoroacetamide. The bottom of the reactor 2 is equipped with a shut-off valve 2 (shut-off valve 2 is an automatic ball valve with a slant rod) 13, which is used to control the conveying of the reaction material to the scraper centrifuge 3.

[0027] A flow meter 10 is installed on the pipeline between the trifluoromethanesulfonyl fluoride buffer tank 1 and the reaction vessel 2 to measure the amount of trifluoromethanesulfonyl fluoride delivered. A regulating valve 11 is installed on the circulating water pipeline of the condenser 6 to adjust the circulating water flow rate and control the condensation effect. A regulating valve 19 is installed on the vacuum pipeline of the solvent buffer tank 7 to adjust the system vacuum level. The trifluoromethanesulfonyl fluoride buffer tank 1, the reaction vessel 2, and the single-cone dryer 5 are made of 316L stainless steel.

[0028] Operating principle of the device: I. Raw material preparation and reaction mixture preparation stage Open the shut-off valve 920 between the solvent buffer tank 7 and the metering tank 8, and the acetonitrile solvent in the solvent buffer tank 7 flows into the metering tank 8; then close the shut-off valve 920, open the shut-off valve 1021 between the metering tank 8 and the reactor 2, and the acetonitrile enters the reactor 2. After the feeding is completed, close the shut-off valve 1021.

[0029] Start the trifluoroacetamide feeder 9 and the potassium fluoride feeder 22, open the shut-off valve 12, and the trifluoroacetamide and potassium fluoride solids are conveyed to the reactor 2 in a closed manner through the feeder 9; start the frame agitator inside the reactor 2, and start the circulating water system of the reactor 2 jacket to pre-cool the reactor.

[0030] II. Fluorination Reaction Stage Trifluoromethanesulfonyl fluoride buffer tank 1: Trifluoromethanesulfonyl fluoride gas enters the reaction vessel 2 after passing through flow meter 10.

[0031] During the reaction, the solvent buffer tank 7 is connected to the vacuum system through the shut-off valve 819 to maintain a micro-vacuum in the system and promptly discharge the trace amounts of gas generated by the reaction; the circulating water pipeline regulating valve 11 of the condenser 6 is in standby mode to prepare for subsequent solvent recovery.

[0032] III. Solid-Liquid Separation and Drying Purification Stage After the reaction is completed, open the automatic ball valve shut-off valve 13 at the bottom of the reactor 2, and the reaction product flows into the scraper centrifuge 3; under the action of the scraper centrifuge 3, the solid waste is deposited at the bottom of the centrifuge and discharged through the shut-off valve 14; the separated liquid phase flows into the solution buffer tank 4 through the shut-off valve 15, and the shut-off valve 15 is closed for temporary storage.

[0033] Open the shut-off valve 16 between the solution buffer tank 4 and the single cone dryer 5, allowing the liquid material to flow into the single cone dryer 5; start the ribbon agitator inside the single cone dryer 5 and turn on the jacketed heat transfer oil system to heat the material and cause the acetonitrile solvent to evaporate; open the shut-off valve 18 between the single cone dryer 5 and the condenser 6, allowing the evaporated acetonitrile vapor to enter the condenser 6; adjust the circulating water regulating valve 11 of the condenser 6 to control the circulating water flow rate, causing the acetonitrile vapor to condense into liquid; the condensed acetonitrile flows into the solvent buffer tank 7 through the outlet of the condenser 6, and then close the shut-off valve 18.

[0034] Examples 1-3 are based on the devices provided in the device embodiments, and are as follows: Example 1 This embodiment provides a method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, specifically including the following steps: Step S1. Add 246 kg of acetonitrile solution to the reactor through a metering tank, start stirring, and add 87 kg of potassium fluoride and 113 kg of trifluoroacetamide to the reactor through a feeder. Stir and dissolve for 2 hours.

[0035] Step S2. Turn on the trifluoromethanesulfonyl fluoride flow meter and introduce 142 kg of trifluoromethanesulfonyl fluoride into the reactor. Maintain the reactor temperature from -10 to 0°C by controlling the flow rate of circulating water in the reactor jacket. Maintain the pressure from atmospheric pressure to 0.1 MPa by controlling the flow rate of trifluoromethanesulfonyl fluoride inlet gas. When the pressure inside the reactor no longer decreases, turn off the inlet flow meter.

[0036] Step S3. Transfer the material in the reactor to a scraped centrifuge for separation. Filter the liquid to a single cone dryer, control the drying temperature at 160℃ and the pressure at -0.09MPa. After drying for 12 hours, 233 kg of N-(trifluoromethanesulfonyl)trifluoroacetamide is obtained, with an overall yield of 95.1% and a purity of 99.9%.

[0037] Example 2 This embodiment provides a method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, specifically including the following steps: Step S1. Add 239 kg of acetonitrile solution to the reactor through a metering tank, start stirring, and add 87 kg of potassium fluoride and 85 kg of trifluoroacetamide to the reactor through a feeder. Stir and dissolve for 2 hours.

[0038] Step S2. Turn on the trifluoromethanesulfonyl fluoride flow meter and introduce 127 kg of trifluoromethanesulfonyl fluoride into the reactor. Maintain the reactor temperature at 0~20℃ by controlling the flow rate of circulating water in the reactor jacket, and maintain the pressure at atmospheric pressure to 0.1 MPa by controlling the flow rate of trifluoromethanesulfonyl fluoride inlet gas. When the pressure in the reactor no longer decreases, turn off the inlet flow meter.

[0039] Step S3. Transfer the material in the reactor to a scraped centrifuge for separation. Filter the liquid to a single cone dryer, control the drying temperature at 160℃ and the pressure at -0.09MPa. After drying for 12 hours, 184 kg of N-(trifluoromethanesulfonyl)trifluoroacetamide is obtained, with an overall yield of 95.3% and a purity of 99.9%.

[0040] Example 3 This embodiment provides a method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, specifically including the following steps: Step S1. Add 256 kg of acetonitrile solution to the reactor through a metering tank, start stirring, and add 87 kg of potassium fluoride and 142 kg of trifluoroacetamide to the reactor through a feeder. Stir and dissolve for 2 hours.

[0041] Step S2. Turn on the trifluoromethanesulfonyl fluoride flow meter and introduce 190 kg of trifluoromethanesulfonyl fluoride into the reactor. Maintain the reactor temperature at 20-40°C by controlling the flow rate of circulating water in the reactor jacket. Maintain the pressure at 0.1-0.2 MPa by controlling the flow rate of trifluoromethanesulfonyl fluoride inlet gas. When the pressure in the reactor no longer decreases, turn off the inlet flow meter.

[0042] Step S3. Transfer the material in the reactor to a scraped centrifuge for separation. The filtrate is dried in a single cone dryer at a controlled temperature of 160°C and a pressure of -0.09 MPa for 12 hours to obtain 321 kg of N-(trifluoromethanesulfonyl)trifluoroacetamide, with an overall yield of 95.0% and a purity of 99.9%. The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, characterized in that, Includes the following steps: Step S1. In the solvent acetonitrile, trifluoroacetamide and potassium fluoride are mixed to form a reaction mixture; Step S2. Trifluoromethanesulfonyl fluoride is introduced into the reaction mixture to react and generate a reaction product containing N-(trifluoromethanesulfonyl)trifluoroacetamide; Step S3. Perform solid-liquid separation on the reaction product to obtain a liquid phase containing N-(trifluoromethanesulfonyl)trifluoroacetamide; and dry the liquid phase to obtain the target product N-(trifluoromethanesulfonyl)trifluoroacetamide.

2. The method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 1, characterized in that, The molar ratio of trifluoromethanesulfonyl fluoride to trifluoroacetamide is 1:(0.9-1.0).

3. The method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 1, characterized in that, The molar ratio of potassium fluoride to trifluoroacetamide is (1.2-1.8):

1.

4. The method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 1, characterized in that, In step S1, the molar ratio of solvent acetonitrile to trifluoroacetamide is (5-7):

1.

5. The method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 1, characterized in that, In step S2, the reaction temperature is from -10℃ to 40℃, and the reaction pressure is from atmospheric pressure to 0.2MPa.

6. The method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 1, characterized in that, In step S3, the drying process is carried out at a temperature ≤160℃, a pressure ≤-0.09MPa, and a time of 12 hours.

7. An apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide, used in the method for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to any one of claims 1 to 6, characterized in that, The apparatus includes: a trifluoromethanesulfonyl fluoride buffer tank (1), a reaction vessel (2), a scraped centrifuge (3), a solution buffer tank (4), a single cone dryer (5), a condenser (6), a solvent buffer tank (7), a metering tank (8), a trifluoroacetamide feeder (9), and a potassium fluoride feeder (22). The trifluoromethanesulfonyl fluoride buffer tank (1) is connected to the reaction vessel (2) and is used to supply trifluoromethanesulfonyl fluoride to the reaction vessel (2); The trifluoroacetamide feeder (9) and the potassium fluoride feeder (22) are both connected to the reactor (2) and are used to add trifluoroacetamide and potassium fluoride to the reactor (2); The bottom of the reactor (2) is connected to the scraped centrifuge (3) for conveying the reaction materials to the scraped centrifuge (3) for solid-liquid separation; The scraper centrifuge (3) is connected to the solution buffer tank (4), and the separated liquid phase material enters the solution buffer tank (4). The solution buffer tank (4) is connected to the single cone dryer (5) and is used to transport liquid phase materials to the single cone dryer (5). The condenser (6) is connected at one end to the single cone dryer (5) and at the other end to the solvent buffer tank (7) for condensing and recovering acetonitrile solvent; The metering tank (8) is connected at one end to the solvent buffer tank (7) and at the other end to the reaction vessel (2), and is used to measure the amount of solvent added to the reaction vessel (2).

8. The apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 7, characterized in that, The reactor (2) is equipped with a frame agitator inside and a jacket outside. The jacket is circulated with water for cooling during the reaction process. The single cone dryer (5) is equipped with a ribbon agitator inside and a jacket outside. The jacket is circulated with heat transfer oil for providing a heat source during the drying process. The reactor (2) is equipped with a shut-off valve (13) at the bottom for controlling the conveying of the reaction material to the scraper centrifuge (3).

9. The apparatus for preparing N-(trifluoromethanesulfonyl)trifluoroacetamide according to claim 7, characterized in that, The trifluoromethanesulfonyl fluoride buffer tank (1), reaction vessel (2), and single cone dryer (5) are made of 316L stainless steel.

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