A green method for preparing nitroamide compounds

Abstract

This invention relates to the field of N-(2,4-dinitrophenyl)-4-nitrobenzamide preparation technology, specifically to a green method for preparing nitramide compounds. The method involves adding a catalyst and dispersant to a reactor and mixing them uniformly. Then, a first and a second stream of materials are simultaneously added dropwise to the reactor for reaction. The temperature within the system is controlled during the dropwise addition. After the dropwise addition is complete, the temperature is increased to continue the reaction. After the reaction is completed, N-(2,4-dinitrophenyl)-4-nitrobenzamide is obtained through post-treatment. The first stream is a dispersion containing 4-nitro-N-phenylbenzamide, and the second stream is a nitrating agent consisting of a uniform mixture of N₂O₅ and nitric acid. This preparation method features high product conversion rate, a mild reaction process, safe and controllable production process, effectively reduces the amount of residual intermediates, and minimizes pollution.

Description

Technical Field

[0001] This invention relates to a green method for preparing nitroamide compounds, belonging to the technical field of N-(2,4-dinitrophenyl)-4-nitrobenzamide preparation. Background Technology

[0002] Nitroamides are important organic intermediates. Because they contain both amide and nitro groups in their structure, these groups can be transformed into various functional groups. As a result, these structures are widely found in a wide variety of natural products, drugs or pesticides. In particular, they can be used as intermediates for various functional materials, pharmaceutical synthesis, and multiple organic chemical reactions.

[0003] Currently, the nitration industry generally employs the traditional mixed acid nitration method, primarily using batch / semi-batch reactors. This method is widely used for the nitration of benzene compounds, phenols, amines, and other compounds, covering pharmaceutical intermediates, pesticides, dyes, and energetic materials. While the technology is mature, it suffers from significant drawbacks: high risks of runaway reactions and explosions, material combustion and autocatalytic decomposition, human error, and equipment aging and malfunctions; excessive mixed acid leads to difficulty in waste acid recovery, nitrogen oxide emissions during the reaction / post-treatment process, high energy consumption for waste acid concentration, and susceptibility to secondary pollution; and there is the issue of regional selective nitration of aromatics. Therefore, green, safe, and efficient nitration technologies are crucial for reducing safety risks and solving the problems associated with the nitration of aromatic compounds.

[0004] Among existing related technologies, patent application CN1098402A provides a non-halogenated method for preparing p-nitroaromatic amides by contacting amides and nitrobenzene, avoiding the expensive removal of halides from wastewater and solving the corrosion problem caused by halides. Patent application FR2502151A1 reports the preparation of N-(2,4-dinitrophenyl)-4-nitrobenzamide using 2,4-dinitroaniline and p-nitrobenzamide; however, from an industrial perspective, the raw material 2,4-dinitroaniline is expensive, resulting in high investment costs. Patent application CN108863832A reports a synthetic method for preparing N-aryl amide compounds, in which amides, copper catalysts, and alkalis are dissolved in an organic solvent, and a halogenated aromatic hydrocarbon is added. This method mainly uses light instead of heating, resulting in high economic costs and a simple process; however, this method is not easy to implement as an industrial synthetic route. Patent JP7660145B2 discloses a method for synthesizing N-(2,4-dinitrophenyl)-4-nitrobenzamide from 2,4-dinitroaniline and 4-nitrobenzyl chloride using a solid acid catalyst. This method aims to solve many problems caused by the conventional use of soluble catalysts.

[0005] The patent application with publication number US4109093A reports a method for synthesizing N-(2,4-dinitrophenyl)-4-nitrobenzamide: N-(2,4-dinitrophenyl)-4-nitrobenzamide is prepared by slow dropwise addition. This patent application does not specify the remaining status of the intermediate N-4-nitro-(4-nitrophenyl)benzamide, the key control conditions, or whether meta-byproduct N-(3,4-dinitrophenyl)-4-nitrobenzamide is generated. Since the raw material is a solid, sulfuric acid with a concentration of less than 100% will damage the stability of the amide bond in the raw material. A large amount of fuming sulfuric acid is required as a solvent to dissolve the raw material before the reaction can proceed, which greatly increases the amount of sulfuric acid used. The amount of waste acid generated after the reaction is large, and the concentration cost is very high. This method greatly limits its industrial development and application value. Summary of the Invention

[0006] This invention addresses the shortcomings of existing technologies by providing a green method for preparing nitroamide compounds. This method achieves high conversion rates in the preparation of N-(2,4-dinitrophenyl)-4-nitrobenzamide, with a mild reaction process, safe and controllable production process, and effectively reduces the residual amount of intermediate N-4-nitro-(4-nitrophenyl)benzamide. It also reduces the pollution caused by large amounts of waste sulfuric acid, strong equipment corrosion, and low reaction efficiency caused by traditional processes.

[0007] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A green method for preparing nitroamide compounds, wherein the preparation method of nitroamide compounds is as follows: After adding the catalyst and dispersant to the reactor and mixing them evenly, the first and second streams of materials are simultaneously added dropwise to the reactor to carry out the reaction. The temperature in the system is controlled during the dropwise addition process. After the dropwise addition is completed, the temperature is raised to continue the reaction. After the reaction is completed, N-(2,4-dinitrophenyl)-4-nitrobenzamide is obtained through post-processing. The first stream of material is a dispersion containing 4-nitro-N-phenylbenzamide, and the second stream of material is a nitrifying agent in which N2O5 and nitric acid are mixed evenly.

[0008] Furthermore, the dispersant is selected from at least one of acetonitrile, dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, nitromethane, glacial acetic acid, and acetic anhydride.

[0009] Preferably, the dispersant is 1,2-dichloroethane.

[0010] Further, the catalyst is selected from at least one of PEG1000-DAIL(HNO3)2, PEG1000-DAIL(HSO4)2, [Et3N(CH2)4SO3H]HSO4, [Et3N(CH2)4SO3H]NO3, [(CH2)4SO3HMim]HSO4, [Et3NH]NO3, [Et3NH]HSO4, [HMim]NO3, [HMim]HSO4, and [(CH2)4SO3HPy]HSO4.

[0011] Preferably, the catalyst is [(CH2)4SO3HMim]HSO4.

[0012] Further, the molar ratio of 4-nitro-N-phenylbenzamide to N2O5 is 1:(2.0-2.30), the mass ratio of nitric acid to dispersant in the system is 1:(1.0-4.0), and the mass ratio of N2O5 to nitric acid is 1:(1.0-5.0).

[0013] Furthermore, the molar ratio of the 4-nitro-N-phenylbenzamide to the catalyst is 1:(0.05~0.35).

[0014] Furthermore, when the first and second streams of material are simultaneously added dropwise to the reactor for reaction, the temperature within the system is controlled at 0-5℃ during the dropwise addition process.

[0015] Furthermore, after the first and second streams of material are added, the temperature is raised to 5-30℃ and the reaction is carried out for 1-4 hours.

[0016] Further, the post-processing operation is as follows: after the reaction is completed, an appropriate amount of ice water is added to the system to quench the reaction, the catalyst is cooled and separated and recovered, the dispersant is recovered by vacuum distillation to obtain the crude product, the crude product is washed with an 8% sodium bicarbonate aqueous solution until alkaline, then washed with pure water until neutral, and the solid-liquid separation and drying are performed to obtain the target product.

[0017] The beneficial effects of this invention are: The green method for preparing nitroamide compounds described in this invention is safe, reliable, and suitable for industrial production. By using a feeding method that involves adding two streams of materials simultaneously, the real-time nitration amount of raw materials in the reactor can be effectively controlled. This avoids the violent reactions caused by local over-abundance of raw materials in the traditional method of "adding raw materials first and then adding nitrifying agents," significantly reducing the risk of nitration reaction, improving process safety and operational reliability, and making it more suitable for large-scale industrial production.

[0018] The green method for preparing nitroamide compounds described in this invention utilizes the synergistic effect of N2O5-nitric acid as a nitrifying agent and a mild reaction process, effectively solving the safety risks associated with the rapid reaction rate and uncontrollable reaction of existing sulfuric acid-nitric acid nitrifying agents. Furthermore, the overall reaction process is greener and more environmentally friendly.

[0019] More specifically, the green method for preparing nitroamide compounds described in this invention uses 1,2-dichloroethane as a dispersant, replacing 98% sulfuric acid in traditional methods. This completely eliminates the adverse effects of low raw material purity, numerous byproducts, and low product yield caused by the instability of raw materials, which negatively impact subsequent reactions such as hydrogenation. It also avoids the environmental pollution and resource waste caused by large amounts of waste acid, fundamentally solving the environmental problems associated with traditional nitration technologies. The dispersant is recyclable and has superior overall performance.

[0020] More specifically, the green preparation method for nitroamide compounds described in this invention uses an ionic liquid catalyst (e.g., methylimidazolium sulfonic acid catalyst [(CH2)4SO3HMim]HSO4), which effectively reduces the residual amounts of the raw material 4-nitro-N-phenylbenzamide and the intermediate N-4-nitro-(4-nitrophenyl)benzamide. The purity and yield of the product N-(2,4-dinitrophenyl)-4-nitrobenzamide are effectively improved, ensuring high product purification and laying a solid foundation for the subsequent hydrogenation process. Furthermore, the catalyst is green, efficient, and environmentally friendly. Attached Figure Description

[0021] Figure 1 The liquid phase spectrum of experimental product number 22 in Example 5; Figure 2 The liquid phase spectrum of experimental product number 24 in Example 6; Figure 3 The liquid phase spectrum of experimental product number 25 in Example 6; Figure 4 The liquid phase spectrum of the experimental product in Comparative Example 3 is shown. Detailed Implementation

[0022] The specific embodiments of the present invention will be described in detail below. The present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein.

[0023] 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 invention pertains. The terminology used is for describing particular embodiments only and is not intended to limit the invention.

[0024] A green method for preparing nitroamide compounds, wherein the preparation method of nitroamide compounds is as follows: 1) Add the catalyst and a small amount of dispersant into the reactor and mix them evenly; 2) Preparation of the first material: Add 4-nitro-N-phenylbenzoamide and dispersant to a dry storage tank, stir and mix thoroughly to obtain a dispersion containing 4-nitro-N-phenylbenzoamide; 3) Preparation of the second material: N2O5 and nitric acid are mixed evenly in proportion at 0-5℃ in a mixing tank to obtain N2O5-nitric acid nitrifying agent; 4) Synchronous dripping reaction: Under stirring, first keep the reactor at 0-5℃, and slowly drip the first and second streams of material into the reactor at the same time, controlling the dripping rate of the two streams to match. The total dripping time is 1-2 hours, and the reaction temperature during the process should not exceed 5℃. After the dripping is completed, raise the reaction temperature to 5-30℃ and continue the reaction for 1-4 hours.

[0025] 5) After the reaction was completed, N-(2,4-dinitrophenyl)-4-nitrobenzamide was obtained by post-treatment.

[0026] The reaction equation is as follows: .

[0027] In step 4), the simultaneous dripping of the first and second streams of material can effectively control the real-time nitration amount of raw materials in the reactor, reduce the accumulation of nitration reaction materials, improve process safety and reliability, and promptly resolve the risk of explosion caused by the reaction temperature runaway and uncontrollable temperature due to the accumulation of raw materials in the reactor to a certain extent before the reaction.

[0028] Specifically, in step 1), the amount of dispersant used to disperse the catalyst should be sufficient to ensure that the agitator can stir normally; there are no restrictions or requirements on the amount used.

[0029] Specifically, the dispersant is selected from at least one of acetonitrile, dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, nitromethane, glacial acetic acid, and acetic anhydride.

[0030] Preferably, the dispersant is 1,2-dichloroethane.

[0031] Specifically, the catalyst is selected from at least one of PEG1000-DAIL(HNO3)2, PEG1000-DAIL(HSO4)2, [Et3N(CH2)4SO3H]HSO4, [Et3N(CH2)4SO3H]NO3, [(CH2)4SO3HMim]HSO4, [Et3NH]NO3, [Et3NH]HSO4, [HMim]NO3, [HMim]HSO4, and [(CH2)4SO3HPy]HSO4.

[0032] Preferably, the catalyst is [(CH2)4SO3HMim]HSO4.

[0033] Specifically, the molar ratio of 4-nitro-N-phenylbenzamide to N2O5 is 1:(2.0-2.30), the mass ratio of nitric acid to dispersant in the system is 1:(1.0-4.0), and the mass ratio of N2O5 to nitric acid is 1:(1.0-5.0). The nitric acid used in this embodiment is fuming nitric acid with a mass concentration of 98%.

[0034] Preferably, the mass ratio of nitric acid to dispersant in the system is 1:(2.0-2.5).

[0035] Preferably, the mass ratio of N2O5 to nitric acid is 1:(2.0-2.5).

[0036] Specifically, the molar ratio of 4-nitro-N-phenylbenzamide to the catalyst is 1:(0.05~0.35).

[0037] Preferably, the molar ratio of 4-nitro-N-phenylbenzamide to the catalyst is 1:(0.05~0.10).

[0038] Specifically, when the first and second streams of material are simultaneously added dropwise to the reactor for reaction, the temperature within the system is controlled at 0-5℃ during the dropwise addition process.

[0039] Specifically, after the first and second streams of material are added, the temperature is raised to 5-30°C and the reaction is carried out for 1-4 hours.

[0040] Preferably, after the first and second streams of material are added, the temperature is raised to 15-20°C and the reaction is carried out for 1-2 hours.

[0041] Specifically, the post-processing operation is as follows: after the reaction is completed, an appropriate amount of ice water is added to the system to quench the reaction, the catalyst is cooled and separated and recovered, the dispersant is recovered by vacuum distillation to obtain the crude product, the crude product is washed with an 8% sodium bicarbonate aqueous solution until alkaline, then washed with pure water until neutral, and the target product is obtained by solid-liquid separation and drying.

[0042] Example 1 A green method for preparing nitroamide compounds, wherein the preparation method of nitroamide compounds is as follows: The dry 500mL four-necked glass reactor was cooled to 0℃. 2.15g of [(CH2)4SO3HMim]HSO4 catalyst and 10g of 1,2-dichloroethane were added to the reactor and stirred until homogeneous. Two mixtures were prepared simultaneously: the first mixture consisted of 24.21 g of 4-nitro-N-phenylbenzoylaniline and 97 g of 1,2-dichloroethane added to a dry mixing tank and stirred to obtain a uniform dispersion; the second mixture consisted of 21.64 g of N₂O₅ and five mixed solutions prepared with 35.62 g, 42.74 g, 53.43 g, 71.23 g, and 106.85 g of 98% fuming nitric acid (representing experiments 1-5). The mixing method involved first adding nitric acid to a mixing tank at 0°C, then slowly adding N₂O₅ while stirring, ensuring the mixing temperature did not exceed 5°C. A total of five sets of experiments were conducted.

[0043] At 0℃, two materials were simultaneously and slowly added dropwise into the reactor, with the total adding time controlled at 1.5 hours. During the adding process, the reaction temperature was kept stable at 0-5℃. After the addition was completed, the reaction was continued at 30℃ for 2 hours. After the reaction was completed, the reaction solution was post-processed to finally obtain a yellow solid powder. The composition of the product was analyzed by liquid phase, and the results are as follows.

[0044] Table 1 Experimental results of Example 1

[0045] Analysis, taking into account the raw materials used, and using the experimental conditions of Experiment No. 3, namely the molar ratio of dinitrogen pentoxide to nitric acid of 1:4.2, generally indicates that more nitric acid is not necessarily better in nitrifying agents; it is sufficient to ensure a significant improvement in the conversion effect of raw materials.

[0046] Example 2 The experimental procedure and reaction conditions were the same as in Example 1, except that the amount of N2O5 was changed. The reaction results are as follows.

[0047] Table 2 Experimental results of Example 2

[0048] Analysis showed that increasing the amount of N2O5 in the nitrifying agent did not have a significant impact on the reaction, and its effect on the reaction was not significant. Therefore, reaction parameters were further optimized using experiment number 6, i.e., the mass ratio of dinitrogen pentoxide to nitric acid of 1:4.14.

[0049] Example 3 The experimental procedure and reaction conditions were as described in Example 1. During the process, the amount of nitric acid was kept constant, and only the amount of dispersant was adjusted. The reaction results are as follows.

[0050] Table 3 Experimental results of Example 3

[0051] Analysis revealed that, with a fixed amount of nitric acid, the reaction effects of experiments 10-14 did not reach those of experiment 6. This indicates that as the amount of dispersant gradually increases, it dilutes the effective concentration of the nitrifying agent, thereby reducing the concentration of nitryl cations and decreasing the reactivity.

[0052] Example 4 The experimental procedure and reaction conditions are as in Example 1. The amount of catalyst was adjusted during the process, and the reaction at a certain temperature is as follows.

[0053] Table 4 Experimental results of Example 4

[0054] Analysis revealed that increasing the catalyst dosage under certain conditions significantly improved the conversion rate of raw materials and intermediates, resulting in a marked reduction in the amount of raw materials remaining. However, with the increase in catalyst dosage, the overall reaction effect remained essentially the same. Considering the economic cost of the catalyst, the parameters of experiment number 15 were selected for further optimization, with a molar ratio of 4-nitro-N-phenylbenzamide to catalyst of 1:0.10.

[0055] Example 5 The experimental procedure is as described in Example 1. Further optimization of the reaction temperature was performed on Experiment No. 15. The reaction time of 2 hours is as follows.

[0056] Table 5 Experimental results of Example 5

[0057] Analysis revealed that optimizing the reaction temperature in five reaction groups resulted in better reaction performance of the raw materials as the temperature gradually increased. When the reaction temperature reached 20℃, the reaction performance was essentially the same, and the reaction process became more stable. This indicates that as the reaction temperature increases, the catalyst and raw materials come into full contact, improving the reaction efficiency and rate. It is speculated that as the reaction temperature gradually increases above 20℃, nitrogen pentoxide gradually decomposes, leading to a decrease in the conversion rate of the raw materials.

[0058] The liquid phase spectrum of product No. 22 is shown below. Figure 1 As shown in Table 6 below, the specific data is as follows.

[0059] Table 6. Liquid Chromatography Data of Experimental Product No. 22

[0060] Example 6 Repeat the experimental conditions of Experiment No. 22, only changing the type of dispersant, specifically acetonitrile, glacial acetic acid, dichloromethane, and carbon tetrachloride (the amount of dispersant added is 107g). The experimental operation steps are as in Example 1. The reaction time is the same at 20°C for 2 hours as follows.

[0061] Table 7 Experimental results of Example 6

[0062] Based on the above experiments, it can be seen that in the solvent selection process, dichloromethane has the same reaction effect as 1,2-dichloroethane. Acetonitrile is too polar, causing the amide bonds of the raw materials to break and hydrolyze into p-nitrobenzoic acid and another unknown impurity. Tetrachloroethylene is less polar than dichloromethane and 1,2-dichloroethane, so its reaction effect is not as good. In the glacial acetic acid dispersant system, the reaction effect is very poor, suggesting that it has adverse effects on the catalyst and the trace amounts of water present. Overall, in this reaction, the polarity of the dispersant should not be too strong or too weak; a moderately weakly polar aprotic solvent is best.

[0063] The liquid phase spectra of experimental products 24 and 25 are as follows: Figure 2 , Figure 3 As shown, the specific data are in Tables 8 and 9 below.

[0064] Table 8. Liquid Chromatography Data of Experimental Product No. 24

[0065] Table 9. Liquid Chromatography Data of Experimental Product No. 25

[0066] Example 7 The experimental conditions of Experiment No. 22 were repeated, except that the catalyst was changed (the amount of catalyst added was 4.30g). The experimental operation steps were the same as in Example 1, and the reaction was carried out at a certain temperature for the same time of 2h. The specific reaction conditions are as follows.

[0067] Table 10 Experimental results of Example 7

[0068] The data table shows that the different ionic liquids all exhibit some catalytic effect on the raw material 4-nitro-N-phenylbenzamide. Overall, the type of acidic ionic liquid does not have the greatest impact on the catalytic effect. The key purpose of using ionic liquids is to promote the efficient decomposition of the nitrating agent, thereby significantly increasing the unit concentration of nitryl cations.

[0069] Comparative Example 1 The experimental procedure and reaction conditions were as in Example 1. The reaction temperature was 20°C, and the nitrating agent was only N2O5. No nitric acid was added. The reaction was as follows.

[0070] Table 11 Experimental results of Comparative Example 1

[0071] The results above show that the reaction effect of the material deteriorates in the absence of nitric acid. The amount of nitrate cations generated by N₂O₅ in the dispersant is limited, and it still exists primarily as N₂O₅ molecules. Nitric acid acts as a catalyst in the entire system, enhancing the ability of N₂O₅ to generate nitrate cations and promoting a more complete reaction. Without the synergistic effect of nitric acid, the nitrification activity of pure dinitrogen pentoxide as a nitrifying agent is unstable, easily leading to intense local reactions, and its purity is significantly lower than that of the N₂O₅-nitric acid composite nitrifying agent system.

[0072] Comparative Example 2 The experimental procedures and reaction conditions were as described in Example 1. The reaction temperature was 20°C, and no catalyst was added to the entire reaction system. The reaction conditions are as follows: Table 12 Experimental results of Comparative Example 2

[0073] The results above show that without a catalyst, the overall activity of the reaction is not high, especially since the intermediate cannot be quickly converted into the product, and the remaining amount is relatively large. This indicates that the catalyst plays an important role in the reaction system, ensuring the efficient progress of the reaction, especially promoting the conversion of the intermediate into the target product.

[0074] Comparative Example 3 The experimental procedure and reaction conditions were the same as in Example 1, with a reaction temperature of 20°C. The only difference was that the dispersant was replaced with fuming sulfuric acid (98% by mass). The reaction was as follows: Table 13 Experimental results of Comparative Example 3

[0075] The results above show that using 1,2-dichloroethane as a dispersant in the preparation of N-(2,4-dinitrophenyl)-4-nitrobenzamide makes the reaction process green, safe, and efficient. At the same time, it effectively reduces the amount of the intermediate N-4-nitro-(4-nitrophenyl)benzamide, ensures the stability of the amide bond in the raw material, and reduces the pollution caused by large amounts of waste sulfuric acid and low reaction efficiency caused by traditional processes.

[0076] The liquid phase spectrum of the experimental product in Comparative Example 3 is shown below. Figure 4 As shown in Table 14 below, the specific data is as follows.

[0077] Table 14 Liquid Chromatography Data of Comparative Example 3 Experimental Products

[0078] In summary, with the assistance of a catalyst, the nitration of 4-nitro-N-phenylbenzamide in a nitration system using N2O5-nitric acid as the nitrifying agent exhibits outstanding reaction performance. The raw material is well protected, resulting in high product purity and positively promoting hydrogenation and subsequent purification processes. Furthermore, both the dispersant and catalyst can be recycled and reused, eliminating the generation of large amounts of wastewater, making it an environmentally friendly green nitration process.

[0079] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A green method for preparing nitroamide compounds, characterized in that, The preparation method of nitroamide compounds is as follows: After adding the catalyst and dispersant to the reactor and mixing them evenly, the first and second streams of materials are simultaneously added dropwise to the reactor to carry out the reaction. The temperature in the system is controlled during the dropwise addition process. After the dropwise addition is completed, the temperature is raised to continue the reaction. After the reaction is completed, N-(2,4-dinitrophenyl)-4-nitrobenzamide is obtained through post-processing. The first stream of material is a dispersion containing 4-nitro-N-phenylbenzamide, and the second stream of material is a nitrifying agent in which N2O5 and nitric acid are mixed evenly.

2. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, The dispersant is selected from at least one of acetonitrile, dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, nitromethane, glacial acetic acid, and acetic anhydride.

3. The method for green preparation of nitroamide compounds according to claim 2, characterized in that, The dispersant is 1,2-dichloroethane.

4. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, The catalyst is selected from at least one of PEG1000-DAIL(HNO3)2, PEG1000-DAIL(HSO4)2, [Et3N(CH2)4SO3H]HSO4, [Et3N(CH2)4SO3H]NO3, [(CH2)4SO3HMim]HSO4, [Et3NH]NO3, [Et3NH]HSO4, [HMim]NO3, [HMim]HSO4, and [(CH2)4SO3HPy]HSO4.

5. The method for green preparation of nitroamide compounds according to claim 4, characterized in that, The catalyst is [(CH2)4SO3HMim]HSO4.

6. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, The molar ratio of 4-nitro-N-phenylbenzamide to N2O5 is 1:(2.0-2.30).

7. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, The mass ratio of nitric acid to dispersant in the system is 1:(1.0-4.0), and the mass ratio of N2O5 to nitric acid is 1:(1.0-5.0).

8. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, The molar ratio of 4-nitro-N-phenylbenzamide to the catalyst is 1:(0.05~0.35).

9. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, When the first and second streams of material are simultaneously added dropwise to the reactor for reaction, the temperature within the system is controlled to be 0-5℃ during the dropwise addition process.

10. The method for green preparation of nitroamide compounds according to claim 1, characterized in that, After the first and second streams of material are added, the temperature is raised to 5-30℃ and the reaction is carried out for 1-4 hours.

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