CN116178182A - Preparation method of 2-methyl-4-methoxy diphenylamine - Google Patents
Preparation method of 2-methyl-4-methoxy diphenylamine Download PDFInfo
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Abstract
The invention provides a preparation method of 2-methyl-4-methoxy diphenylamine, and relates to the field of organic synthesis. The preparation method comprises the following steps: adding acetanilide, an acid binding agent, a copper catalyst, toluene and 4-bromomethyl ether into a reaction vessel, heating and carrying out condensation reaction to obtain a first mixed product; sequentially adding strong alkali and a hydrolytic agent into the condensation product in the first mixture, and controlling the temperature to be not higher than 200 ℃ for reflux reaction to obtain a second mixed product; and sequentially carrying out negative pressure distillation, extraction, concentration, crystallization, washing and drying on the second mixed product to obtain the 2-methyl-4-methoxy diphenylamine. Wherein, the hydrolytic agent in the step (2) adopts a mixture of water and alcohol, and the water is: the mass ratio of the alcohol is 1: 0.5-2; the mass content of the condensed product in the first mixed product is more than or equal to 80 percent, the mass content of the 4-bromomethyl ether is less than or equal to 2 percent, and the mass content of the acetanilide is less than or equal to 15 percent.
Description
Technical Field
The invention relates to the technical field of organic synthesis and chemical raw material preparation, in particular to a preparation method of 2-methyl-4-methoxy diphenylamine.
Background
2-methyl-4-methoxyl diphenylamine (DPA for short) is mainly used as an important intermediate of pressure-sensitive dyes, medicines, rubbers and pesticides.
The traditional process for preparing 2-methyl-4-methoxy diphenylamine uses m-cresol as a starting material, and obtains 2-methyl-4-methoxy bromobenzene through dimethyl sulfate etherification and bromine bromination, then the 2-methyl-4-methoxy bromobenzene is condensed with acetanilide, and then the 2-methyl-4-methoxy diphenylamine is obtained through hydrolysis under the strong alkaline condition. The process has long route, complex reaction, low yield and more three wastes; methyl sulfate is used for m-cresol etherification, and is a highly toxic chemical; bromine is consumed in a large amount, and this increases the cost due to the high price of bromine. These factors limit the application of conventional processes.
The synthesis technology of 2-methyl-4-methoxy diphenylamine reported in the current literature mainly comprises the following steps: 2-methyl-4-methoxy aniline and halogenated benzoic acid are added with an acid binding agent to generate condensation reaction in toluene to prepare a target product, and the reaction process system is subjected to negative pressure water removal. And then carrying out acid washing and three times of water washing to obtain a target product, and decarboxylating to obtain the product 2-methyl-4-methoxy diphenylamine. The salt generated by the reaction with the acid binding agent is insoluble in toluene, so that a large amount of solids, even caking, can be generated in a system by adding all the acid binding agents at one time, seriously affects the smooth performance of experiments, and causes incomplete raw material conversion, low product yield, and the recovery of unreacted raw materials is time-consuming and labor-consuming, excessive alkali and salt in the product need to be washed for many times, and the production cost is high; the reaction needs high vacuum distillation and water separation, so the process has high energy consumption; and due to the negative pressure, the boiling point of the material is reduced, the reflux temperature of the system is lower, and the reaction is slower. Therefore, the preparation process is difficult to industrially popularize at present.
Disclosure of Invention
The inventors found that: 4-bromine m-methyl ether (also called 4-bromine-m-methyl anisole) and acetanilide are subjected to condensation reaction in the presence of an acid binding agent and a copper catalyst, then the condensation product is subjected to hydrolysis reflux reaction under alkaline condition, and finally the 2-methyl-4-methoxy diphenylamine product can be obtained through extraction, solvent recovery, refining and crystallization. However, in the process, a large amount of aniline is generated by the hydrolysis of the acetanilide in the hydrolysis process, part of aniline can be separated out through phase separation, and part of aniline still remains in the product, so that the content is high, and the stability of the product in the storage process is poor. The inventor finds through a plurality of experiments that the water is used as a hydrolysis agent in the hydrolysis reaction process, and the water is modified to be a mixture of water and alcohol as the hydrolysis agent, so that the solubility of solid-liquid two phases can be increased, the hydrolysis rate of condensation products and acetanilide is improved, the more thorough hydrolysis of the acetanilide in the hydrolysis reaction stage is ensured, and the production of aniline by continuous hydrolysis of the acetanilide in the subsequent reaction process is avoided.
The invention provides a preparation method of 2-methyl-4-methoxy diphenylamine, which comprises the following steps:
(1) Adding acetanilide, an acid binding agent, a copper catalyst, toluene and 4-bromomethyl ether into a reaction vessel, heating and carrying out condensation reaction to obtain a first mixed product.
(2) And (3) dissolving the condensation product in the first mixed product in toluene, then carrying out negative pressure heating, then sequentially adding strong alkali and dropwise adding a hydrolysis agent, and carrying out reflux reaction at the temperature of not higher than 200 ℃ to obtain a second mixed product.
(3) And sequentially carrying out negative pressure distillation, extraction, concentration, crystallization, washing and drying on the second mixed product to obtain the 2-methyl-4-methoxy diphenylamine.
Wherein the hydrolytic agent in the step (2) adopts a mixture of water and alcohol; water: the mass ratio of the alcohol is 1: 0.5-2.
The mass content of the condensation product in the first mixed product is more than or equal to 80 percent, the mass content of the 4-bromomethyl ether is less than or equal to 2 percent, and the mass content of the acetanilide is less than or equal to 15 percent.
Compared with the prior art, the invention has the beneficial effects that at least one of the following is included:
(1) Compared with the prior art, the preparation method of the 2-methyl-4-methoxy diphenylamine has the advantages that in the hydrolysis reaction process, water is used as a hydrolysis agent, and the mixture of water and alcohol is used as the hydrolysis agent, so that the solubility of solid-liquid two phases can be increased, the hydrolysis rate of condensation products and acetanilide is improved, the more thorough hydrolysis of acetanilide in the hydrolysis reaction stage is ensured, and the yield of products is further improved.
(2) Compared with the prior art, the preparation method of the 2-methyl-4-methoxy diphenylamine is matched with the hydrolysis reaction step through the negative pressure distillation step, so that the aniline content is further reduced, and the product quality is improved.
(3) In the invention, a small amount of sodium sulfite is added as a reducing agent in the refining process, so that the product color change caused by oxidation of residual trace aniline is avoided. The residual quantity of the color-changing group substances in the product can be controlled below 0.0005%, the shelf life of the product is prolonged from 1 month to more than 1-2 years.
(4) The mass content of the 2-methyl-4-methoxy diphenylamine prepared by the method is not less than 99%, and the mass content of the aniline is not more than 0.0005%.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and do not constitute a limitation on the invention. In the drawings:
FIG. 1 shows a reaction scheme of 2-methyl-4-methoxydiphenylamine of the present invention;
FIG. 2 shows a process flow diagram of a process for the preparation of 2-methyl-4-methoxydiphenylamine of the present invention.
Detailed Description
In order to more clearly illustrate the general inventive concept, a detailed description is given below by way of example with reference to the accompanying drawings.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those described herein, and therefore the scope of the present invention is not limited to the specific embodiments disclosed below. In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
In one exemplary embodiment of the present invention, a method for preparing 2-methyl-4-methoxydiphenylamine includes the steps of:
adding acetanilide, an acid binding agent, a copper catalyst, toluene and 4-bromomethyl ether into a reaction vessel, heating and carrying out condensation reaction to obtain a first mixed product. The acid binding agent may be one of sodium carbonate or sodium hydroxide. The copper catalyst can be at least one of copper, cuprous chloride and cupric chloride. If the acid binding agent is sodium hydroxide, the acetanilide comprises the following components: the molar ratio of the 4-bromomethyl ether can be 1.05-1.15:1.2-1.5:0.01-0.05:1. If the acid binding agent is sodium carbonate, the acetanilide comprises the following components: the molar ratio of the 4-bromomethyl ether can be 1.05-1.15:0.6-0.75:0.01-0.05:1.
The mass content of the condensed product in the obtained first mixed product is more than or equal to 80 percent, the mass content of the 4-bromomethyl ether is less than or equal to 2 percent, and the mass content of the acetanilide is less than or equal to 15 percent; and (3) dissolving the condensation product in the first mixed product in toluene, and then carrying out negative pressure heating to 140-175 ℃ for distillation, wherein the purpose of the negative pressure heating is to facilitate complete distillation of the toluene solvent, and if the temperature is lower than 140 ℃, the toluene distillation is incomplete, and if the temperature is higher than 175 ℃, the material is distilled out, so that the product yield is affected. Then adding strong alkali and dropwise adding a hydrolysis agent in sequence, and carrying out reflux reaction at the temperature of not higher than 200 ℃ to obtain a second mixed product. If the temperature is higher than 200 ℃, side reactions are increased, and the product yield is affected. In particular, the strong base may be sodium hydroxide or potassium hydroxide. The hydrolytic agent is a mixture of water and alcohol, and the alcohol is one or two of methanol, ethanol or propanol; the water: the mass ratio of the alcohol is 1: 0.5-2; preferably, the water: the mass ratio of the alcohol is 1: 0.8-1.5; more preferably, the water: the mass ratio of the alcohol is 1:1 to 1.3. The mass ratio of the strong alkali to the hydrolytic agent to the condensation product is 0.3-0.5: 0.05-0.1:1.
In addition, the mass content of 2-methyl-4-methoxydiphenylamine in the obtained second mixed product is not less than 90%, the mass content of the condensed product is not more than 1%, the mass content of acetanilide is not more than 0.05%, and the mass content of aniline is not more than 4%. Preferably, the mass content of 2-methyl-4-methoxyl diphenylamine in the second mixed product is not less than 92%, the mass content of the condensed product is not more than 0.5%, and the mass content of aniline is not more than 3%.
And sequentially carrying out negative pressure distillation, extraction, concentration, crystallization, washing and drying on the second mixed product to obtain the 2-methyl-4-methoxy diphenylamine. Wherein the mass content of the 2-methyl-4-methoxy diphenylamine is not less than 99%, and the mass content of the aniline is not more than 0.0005%. In order to further improve the stability of the 2-methyl-4-methoxy diphenylamine product, a small amount of sodium sulfite can be added into the concentrated material, and the mass ratio of the sodium sulfite to the 4-bromom-methyl ether is as follows: 4-bromomethyl ether=1:50-200.
The preparation method of the 2-methyl-4-methoxy diphenylamine comprises the following specific steps:
1. and (3) a condensation reaction stage.
Sequentially adding acetanilide, an acid binding agent, a copper catalyst, toluene and 4-bromomethyl ether into a reaction vessel, heating to perform condensation reaction, sampling and analyzing after 15 hours of reaction, if the mass content of the condensation product in the sample is more than or equal to 80%, the mass content of the 4-bromomethyl ether is less than or equal to 2%, and the mass content of the acetanilide is less than or equal to 15%, performing reaction qualification, filtering to obtain the condensation product, slowly adding toluene and water, completely dissolving the condensation product in the toluene and the water to perform washing layering, separating out a water phase, filtering out copper catalyst solids from an oil phase, and preparing for hydrolysis reaction.
2. And (3) a hydrolysis reaction stage.
Slowly heating to 140-175 ℃ under the negative pressure condition, evaporating toluene in an oil phase, regulating the system to normal pressure, adding sodium hydroxide into a reaction container, and slowly dropwise adding a hydrolysis agent into the reaction container, wherein water in the hydrolysis agent is as follows: and (3) carrying out reflux reaction at the temperature of not more than 200 ℃ with the mass ratio of alcohol being 1:0.5-2, separating aniline by an oil-water separator, reacting for 6-10 hours, and then sampling and analyzing until the mass content of DPA in the reactant is more than or equal to 90%, the mass content of condensation product is less than or equal to 1%, and finishing the hydrolysis reaction.
The reaction principle of 2-methyl-4-methoxydiphenylamine is shown in reference to FIG. 1.
3. Refining stage
In order to further reduce the aniline content in the product, the hydrolyzed product is distilled and purged, the negative pressure distillation is carried out at 170-200 ℃, the aniline is distilled out as far as possible, no obvious fraction is distilled out, nitrogen is introduced into the reaction vessel for flat pressure, the system is purged, replaced and sampled and analyzed, the aniline mass content in the product after the negative pressure distillation is less than or equal to 0.1%, and the acetanilide mass content is less than or equal to 0.01%. Preferably, the aniline mass content in the product after the negative pressure distillation is less than or equal to 0.09%, and the acetanilide mass content is less than or equal to 0.006%.
And then sequentially extracting and concentrating the product subjected to negative pressure distillation, adding sodium sulfite into the concentrated product, wherein the mass ratio of the sodium sulfite to the 4-bromomethyl ether is 1:50-200, pumping negative pressure to-0.1 MPa, heating to 210 ℃ to distill out a front fraction, replacing a receiving bottle, continuously slowly heating to 240-260 ℃ under the pressure of-0.1 MPa, and continuously distilling until no fraction is distilled out.
Heating the distilled material to more than 80 ℃ to dissolve, adding methanol, preserving heat at 60-70 ℃ for 30min, slowly cooling for crystallization, filtering out the solid material when the temperature is reduced to 5-10 ℃, then soaking and washing the material with methanol at about 0 ℃, and drying the soaked and washed material in a vacuum oven for 2h to obtain 2-methyl-4-methoxyl diphenylamine, wherein the mass content of the 2-methyl-4-methoxyl diphenylamine is not less than 99%, and the mass content of the aniline is not more than 0.0005%. Referring to FIG. 2, FIG. 2 shows a process flow diagram of the process for preparing 2-methyl-4-methoxydiphenylamine of the present invention.
Example 1
1. Condensation reaction stage
143.75g of acetanilide, 70g of sodium carbonate, 3.875g of cuprous chloride, 200g of 4-bromom-methyl ether and 30g of toluene are sequentially added into a 1000ml four-neck flask, the temperature is raised for condensation reaction, sampling analysis is carried out after the reaction is carried out for 15 hours, the analysis result refers to the process 1 in the table 1, about 320g of condensation product is obtained through filtration, toluene and water are slowly added, all the condensation product is dissolved in the toluene and the water for washing and layering, the water phase is separated, and the oil phase is prepared for hydrolysis reaction after the cuprous chloride solid is filtered out.
2. Hydrolysis reaction stage
Slowly heating to 140-175 ℃ under the negative pressure condition to evaporate toluene in an oil phase, regulating the system to normal pressure, adding 137.5g of sodium hydroxide into a reaction container, slowly dropwise adding 20g of a hydrolysis agent into the reaction container, wherein the alcohol is methanol, and the water in the hydrolysis agent is as follows: the mass ratio of methanol is 1:0.8, the dropping speed is controlled, the dropping is completed within 1-2 hours, the temperature is kept at not more than 190 ℃ in the dropping process, reflux reaction is carried out, aniline is separated out through an oil-water separator, sampling analysis is carried out after the reaction is carried out for 8 hours, the analysis result is shown in the procedure 2 in the table 1, and the hydrolysis reaction is finished.
3. Refining stage
And (3) carrying out distillation and purging on the hydrolyzed product, carrying out negative pressure distillation at 180 ℃, introducing nitrogen into the reaction vessel for flat pressure after no obvious fraction is distilled out, carrying out purging, replacement and sampling analysis on the system, and the analysis results are shown in a working procedure 3 in the table 1.
And then sequentially extracting and concentrating the product subjected to negative pressure distillation, adding 2g of sodium sulfite into about 220g of concentrated product, pumping negative pressure to-0.1 MPa, heating to 210 ℃ to distill out a front fraction, replacing a receiving bottle, and continuously slowly heating to 240 ℃ under the pressure of-0.1 MPa to distill out no fraction.
Heating the distilled material to 90 ℃ to dissolve, adding 650g of methanol, preserving heat at 65 ℃ for 30min, slowly cooling to crystallize, filtering out the solid material when the temperature is reduced to 5-10 ℃, then soaking and washing the material with methanol at about 0 ℃, and drying the soaked and washed material in a vacuum oven for 2h to obtain 2-methyl-4-methoxydiphenylamine, wherein the purity of the product is shown in a procedure 4 in a reference table 1.
Three batches of 2-methyl-4-methoxydiphenylamine were prepared separately by the preparation method of example 1, as shown in Table 1.
TABLE 1
Example 2
The main difference on the basis of example 1 is that the mass content of condensation product in the first mixed product obtained is not less than 85%. Water in the hydrolyzer: the mass ratio of the ethanol is 1:1.5.
TABLE 2
As can be seen by referring to tables 1 and 2, the mass content of acetanilide in the 2-methyl-4-methoxydiphenylamine prepared by the preparation method of the invention is not higher than 0.0005%, the mass content of aniline is not higher than 0.0005%, the mass content of DPA is not lower than 99%, and the DPA yield is not lower than 85%.
Comparative example 1
On the basis of example 1, in the hydrolysis reaction stage, water in the hydrolysis agent: the mass ratio of methanol is 1:0.2. The two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 1 are shown in Table 3.
TABLE 3 Table 3
Comparative example 2
On the basis of example 1, the difference is that in the hydrolysis reaction stage, water in the hydrolysis agent: the mass ratio of methanol is 1:0.4. Two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 2 are shown in Table 4.
TABLE 4 Table 4
Referring to tables 3 and 4, it can be seen that the main difference between comparative example 1 and comparative example 2 and example 1 is that the hydrolysis rate of the condensation product and acetanilide is reduced when the amount of methanol in the hydrolysis agent is low in comparative example 1 and comparative example 2. The condensation product content in the hydrolysis reaction stage is excessive, and the acetanilide content is excessive. For example, the mass content of the condensation product in the hydrolysis reaction step in comparative example 1 and comparative example 2 exceeds 5% and the mass content of acetanilide exceeds 0.5%. The yield of the final 2-methyl-4-methoxy diphenylamine product is lower than 80 percent.
Comparative example 3
On the basis of example 1, the difference is that in the hydrolysis reaction stage, water in the hydrolysis agent: the mass ratio of methanol is 1:2.5. Two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 3 are shown in Table 5.
TABLE 5
Referring to Table 5, the main difference in comparative example 3 is that when the content of methanol in the hydrolyzing agent is too large, the hydrolysis rate of the condensation product and acetanilide in the hydrolysis reaction stage is lowered. For example, the mass content of the condensation product in the hydrolysis reaction stage in comparative example 3 exceeds 8% and the mass content of acetanilide exceeds 1%. The yield of the final 2-methyl-4-methoxy diphenylamine product is lower than 80 percent.
Comparative example 4
The difference on the basis of example 1 is that the hydrolysis stage was carried out with the hydrolysis agent being water, the mass of water being 20g, and no alcohol being added, the two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 4 are shown in Table 6.
TABLE 6
Comparative example 5
The main difference on the basis of example 1 is that the mass content of the condensation product in the first mixed product obtained is < 80%, the mass content of 4-bromomethyl ether is > 2% and the mass content of acetanilide is > 15%. Two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 5 are shown in Table 7.
TABLE 7
As shown in Table 7, it can be seen that the main difference is that the mass content of the condensed product in the first mixed product in comparative example 5 is < 80%, the mass content of 4-bromomethyl ether is > 2%, the mass content of acetanilide is > 15%, and the product yield is slightly lowered as compared with example 1.
Comparative example 6
The main difference on the basis of example 1 is that no distillation purge is performed after the hydrolysis reaction is completed. The parameters relating to the two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 6 are shown in Table 8.
TABLE 8
Referring to Table 8, it can be seen that the main difference is that the hydrolysis reaction of comparative example 6 was completed without performing the distillation purge step. The yield of the product was less affected than in example 1, but the quality of the product was affected. For example, the product obtained in comparative example 6 had a content of aniline by mass exceeding 0.005%.
Comparative example 7
On the basis of example 1, the difference is that 2g of sodium sulfite was not added to the concentrated mass. The parameters relating to the two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 7 are shown in Table 9.
TABLE 9
Referring to Table 9, it can be seen that the main difference is that 2g of sodium sulfite was not added to the concentrated material in comparative example 7. The yield of the product was less affected than in example 1, but the quality of the product was affected. For example, the product obtained in comparative example 7 had a content of aniline by mass exceeding 0.005%.
Comparative example 8
On the basis of example 1, the difference is that 5g of sodium sulfite was added to the concentrated mass. Sodium sulfite: the mass ratio of the 4-bromomethyl ether is 1:40. The parameters relating to the two batches of 2-methyl-4-methoxydiphenylamine prepared separately in comparative example 8 are shown in Table 10.
Table 10
Referring to table 10, it can be seen that when the content of sodium sulfite added is too large, the quality of the product is not greatly affected and the purity of the product is slightly lowered as compared with example 1.
The foregoing is merely exemplary of the present invention and is not intended to limit the present invention. Various modifications and variations of the present invention will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are to be included in the scope of the claims of the present invention.
Claims (10)
1. A method for preparing 2-methyl-4-methoxy diphenylamine, which is characterized by comprising the following steps:
(1) Adding acetanilide, an acid binding agent, a copper catalyst, toluene and 4-bromomethyl ether into a reaction vessel, heating and carrying out condensation reaction to obtain a first mixed product;
(2) Dissolving condensation products in the first mixed product in toluene, then carrying out negative pressure heating, sequentially adding strong alkali and dropwise adding a hydrolysis agent, and carrying out reflux reaction at the temperature of not higher than 200 ℃ to obtain a second mixed product;
(3) Sequentially carrying out negative pressure distillation, extraction, concentration, crystallization, washing and drying on the second mixed product to obtain 2-methyl-4-methoxy diphenylamine;
wherein, the hydrolytic agent in the step (2) adopts a mixture of water and alcohol, and the water is: the mass ratio of the alcohol is 1: 0.5-2;
the mass content of the condensation product in the first mixed product is more than or equal to 80 percent, the mass content of the 4-bromomethyl ether is less than or equal to 2 percent, and the mass content of the acetanilide is less than or equal to 15 percent.
2. The method of claim 1, wherein the water: the mass ratio of the alcohol is 1:0.8 to 1.5.
3. The preparation method according to claim 1, wherein the mass content of the condensation product in the first mixed product is 85% -90%, the mass content of 4-bromom-methyl ether is less than or equal to 1%, and the mass content of acetanilide is less than or equal to 12%.
4. The method of claim 1, wherein the acid binding agent is sodium carbonate or sodium hydroxide.
5. The method according to claim 1, wherein the step of negative pressure distillation comprises the steps of carrying out negative pressure distillation on the second mixed product at 170-200 ℃, introducing nitrogen into the reaction vessel for flat pressure after no obvious fraction is distilled out, and carrying out purging and replacement on the system.
6. The method of claim 1, wherein the alcohol is one of methanol, ethanol, or propanol.
7. The method of claim 1, wherein the copper catalyst is one or both of copper and cuprous chloride.
8. The method according to claim 1, wherein the crystallization step comprises adding sodium sulfite to the concentrated material, followed by the crystallization step; the mass ratio of the sodium sulfite to the 4-bromomethyl ether is 1:50-200.
9. The method according to claim 1, wherein the mass content of 2-methyl-4-methoxydiphenylamine in the second mixed product is not less than 90%, the mass content of condensed product is not more than 1%, and the mass content of aniline is not more than 4%.
10. The preparation method according to claim 1, wherein the mass content of the prepared 2-methyl-4-methoxydiphenylamine is not less than 99%, and the mass content of the aniline is not more than 0.0005%.
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| JPS60214763A (en) * | 1984-04-06 | 1985-10-28 | Hodogaya Chem Co Ltd | Production of diphenylamine compound |
| US5679856A (en) * | 1995-02-14 | 1997-10-21 | Ciba-Geigy Corporation | Process for preparing diphenylamines |
| US20070073086A1 (en) * | 2005-09-28 | 2007-03-29 | Appleton Papers Inc. | Process for manufacturing diphenylamines |
| CN101786956A (en) * | 2010-02-05 | 2010-07-28 | 山东默锐化学有限公司 | Method for deacylating N-acylated diphenylamine or ring-substituted derivatives thereof |
| CN103086898A (en) * | 2012-07-11 | 2013-05-08 | 山东道可化学有限公司 | Preparation method of diphenylamine or ring-substituted derivative thereof |
| CN104262167A (en) * | 2014-09-30 | 2015-01-07 | 无锡绿色分离应用技术研究所有限公司 | Preparation method of diarylamine ramification |
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2023
- 2023-04-27 CN CN202310464738.2A patent/CN116178182B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60214763A (en) * | 1984-04-06 | 1985-10-28 | Hodogaya Chem Co Ltd | Production of diphenylamine compound |
| US5679856A (en) * | 1995-02-14 | 1997-10-21 | Ciba-Geigy Corporation | Process for preparing diphenylamines |
| US20070073086A1 (en) * | 2005-09-28 | 2007-03-29 | Appleton Papers Inc. | Process for manufacturing diphenylamines |
| CN101786956A (en) * | 2010-02-05 | 2010-07-28 | 山东默锐化学有限公司 | Method for deacylating N-acylated diphenylamine or ring-substituted derivatives thereof |
| CN103086898A (en) * | 2012-07-11 | 2013-05-08 | 山东道可化学有限公司 | Preparation method of diphenylamine or ring-substituted derivative thereof |
| CN104262167A (en) * | 2014-09-30 | 2015-01-07 | 无锡绿色分离应用技术研究所有限公司 | Preparation method of diarylamine ramification |
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