CN107556201B - Process for preparing m-aminophenol - Google Patents

Abstract

The invention relates to a process method for preparing m-aminophenol,the method belongs to the technical field of chemical material preparation, solves the technical problem of limitation when phenyl acetate is used as a preparation raw material, and has the advantages of simple operation, high product yield, easy control of reaction and the like. The solution is as follows: preparing m-phenyl carboxy acetate after preparing m-toluyl acetate, preparing m-aminophenol from the prepared m-phenyl carboxy acetate: a. get C₉H₈O₄Adding the reagent into an ethyl acetate solution, fully stirring until the reagent is completely dissolved, dropwise adding thionyl chloride into the system under the condition of ice-water bath, preserving the heat for 1 plus or minus 0.5 hour, heating to 60 ℃, and refluxing; b. adding triethylamine and hydroxylamine hydrochloride into the system under the condition of ice-water bath, preserving the temperature for 2 hours, and then heating to room temperature; c. spin-drying the solvent on a rotary evaporator, then adding water and potassium carbonate, and heating to 60-70 ℃ for hydrolysis; d. extracting the solution with ethyl acetate, determining whether the extraction is complete by adopting thin-layer chromatography, and obtaining the finished product of m-aminophenol after the extraction is finished.

Description

Process for preparing m-aminophenol

Technical Field

The invention belongs to the technical field of chemical material preparation, and particularly relates to a process method for preparing m-aminophenol.

Background

M-aminophenol is an important fine chemical raw material and an organic intermediate, and is widely applied in the fields of petrochemical industry, pesticides, medicines, dyes and the like. So far, various processes for synthesizing m-aminophenol have been developed, mainly including nitrobenzene process, resorcinol ammonolysis process, m-nitrophenol electrolysis process, aniline hydroxylation process, m-phenylenediamine hydrochloric acid hydrolysis process and the like, but most of them have the problems of backward process, serious pollution, high cost, low yield and selectivity and high requirement on equipment.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a process method for preparing m-aminophenol.

The invention is realized by the following technical scheme.

A process method for preparing m-aminophenol comprises the following steps in sequence:

i, preparing m-cresol acetate as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₇H₈O+CH₃CClO→C₉H₁₀O₂+HCl↑

B. the preparation steps are as follows:

firstly, taking 21.6g of m-cresol into a 100ml Erlenmeyer flask, and then adding 15ml of dichloromethane into the Erlenmeyer flask to serve as a solvent; secondly, under the condition of ice-water bath at 0-5 ℃, dropwise adding 15.7g of acetyl chloride reagent into the system by using a constant-pressure dropping funnel, and fully reacting for 30-60 minutes; thirdly, continuing to react for 60 minutes at low temperature under the condition of ice-water bath at 0-5 ℃, then starting to heat, controlling the temperature of the system at 60 +/-5 ℃, reacting for 2-3 hours, and introducing tail gas generated by the reaction into a sodium hydroxide aqueous solution for absorption; finally, taking out a solid mixture generated after the reaction in the triangular flask, and removing unreacted solvent dichloromethane in the solid mixture by using a rotary evaporator to prepare m-toluyl acetate for later use;

II, preparing m-carboxyl phenyl acetate serving as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₉H₁₀O₂+2KMnO₄→C₉H₈O₄+2M_nO₂+2KOH

B. the preparation steps are as follows:

a. taking 7.5g of m-toluyl acetate prepared in the previous step I into a 100ml triangular flask, adding 50ml of water, fully stirring, then adding 5ml of glacial acetic acid, and heating the system to 60-80 ℃;

b. weighing 243g of potassium permanganate, slowly adding a small amount of potassium permanganate into a m-toluyl acetate system for multiple times, and keeping the system temperature at 50-80 ℃ for reacting for 8-10 hours after the potassium permanganate is completely added; after the purple color in the system is completely faded, heating the system to 90-110 ℃, reacting for 2-3 hours, determining the pH value of the system solution to be 8 +/-0.2 after the reaction is finished, filtering the generated solution while the solution is hot, and repeatedly washing a filter cake used in the filtering process for 3 times by using hot water after the filtration for the next use;

c. regulating the pH of the filtrate prepared in the step b to be less than or equal to 1 by hydrochloric acid, keeping the solution to have no precipitate or trace precipitate, extracting by using ethyl acetate, and removing an extracting agent in the mixture by using a rotary evaporator after extraction to prepare a m-carboxyl phenyl acetate solid product for later use;

III, preparation of m-aminophenol

A. The reaction equation is as follows:

C₉H₈O₄+SOCl₂→C₉H₇ClO₃+SO₂+HCl；

C₉H₇ClO₃+NH₂OH·HCl→C₉H₉NO₄+2HCl；

B. the preparation steps are as follows:

a. get C₉H₈O₄Adding 1.73g of the reagent into 15ml of ethyl acetate solution, fully stirring until the reagent is completely dissolved, dropwise adding 1.78g of thionyl chloride into the system under the condition of ice-water bath at the temperature of 0-5 ℃, preserving heat for 1 +/-0.5 hour, heating to 60 ℃, and refluxing for 6-8 hours;

b. adding 7.1g of triethylamine and 0.96g of hydroxylamine hydrochloride into the system under the condition of ice-water bath at the temperature of 0-5 ℃, preserving the temperature for 2 hours, and then heating to room temperature;

c. spin-drying the solvent on a rotary evaporator, adding 50ml of water and 2.6g of potassium carbonate, and heating to 60-70 ℃ for hydrolysis for 2-3 hours;

d. extracting the solution with ethyl acetate for 3-4 times, determining whether the extraction is complete by adopting thin-layer chromatography, developing the color in an iodine cylinder, and obtaining the finished product of m-aminophenol after the extraction is completed.

Compared with the prior art, the invention has the following beneficial effects.

The process method for preparing m-aminophenol provided by the invention has the advantages of mild reaction conditions, easily available raw materials, simple operation, high product yield, easy control of reaction and the like, and is beneficial to industrial production.

Detailed Description

The present invention will be described in detail with reference to the following examples: in this embodiment, the technical solution of the present invention is used as a precondition for implementation, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

Example one

The process method for preparing m-aminophenol in the embodiment is sequentially carried out according to the following steps:

i, preparing m-cresol acetate as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₇H₈O+CH₃CClO→C₉H₁₀O₂+HCl↑

B. the preparation steps are as follows:

firstly, taking 21.6g of m-cresol into a 100ml Erlenmeyer flask, and then adding 15ml of dichloromethane into the Erlenmeyer flask to serve as a solvent; secondly, under the condition of ice-water bath at the temperature of 1 ℃, 15.7g of acetyl chloride reagent is dripped into the system by a constant pressure dropping funnel, and the reaction is carried out for 30 minutes; thirdly, continuing to react for 60 minutes at a low temperature under the condition of ice-water bath at the temperature of 1 ℃, then starting to heat, controlling the temperature of the system at 55 ℃, reacting for 2 hours, and introducing tail gas generated by the reaction into a sodium hydroxide aqueous solution for absorption; finally, taking out a solid mixture generated after the reaction in the triangular flask, and removing unreacted solvent dichloromethane in the solid mixture by using a rotary evaporator to prepare m-toluyl acetate for later use;

II, preparing m-carboxyl phenyl acetate serving as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₉H₁₀O₂+2KMnO₄→C₉H₈O₄+2MnO₂+2KOH

B. the preparation steps are as follows:

a. taking 7.5g of m-toluyl acetate prepared in the previous step I into a 100ml triangular flask, adding 50ml of water, fully stirring, then adding 5ml of glacial acetic acid, and heating the system to 60 ℃;

b. 243g of potassium permanganate is weighed and slowly added into a m-toluyl acetate system for a plurality of times in a small amount, and after the potassium permanganate is completely added, the temperature of the system is kept at 50 ℃ for reaction for 8 hours; heating the system to 90 ℃ after purple color in the system is completely faded, reacting for 2 hours, measuring the pH value of the system solution to be 7.8 after the reaction is finished, filtering the generated solution while the solution is hot, and repeatedly washing filter cakes used in the filtering process for 3 times by using hot water after filtering for the next use;

c. regulating the pH of the filtrate prepared in the step b to be less than or equal to 1 by hydrochloric acid, keeping the solution to have no precipitate or trace precipitate, extracting by using ethyl acetate, and removing an extracting agent in the mixture by using a rotary evaporator after extraction to prepare a m-carboxyl phenyl acetate solid product for later use;

III, preparation of m-aminophenol

A. The reaction equation is as follows:

C₉H₈O₄+SOCl₂→C₉H₇ClO₃+SO₂+HCl；

C₉H₇ClO₃+NH₂OH·HCl→C₉H₉NO₄+2HCl；

B. the preparation steps are as follows:

a. get C₉H₈O₄Adding 1.73g of reagent into 15ml of ethyl acetate solution, fully stirring until the reagent is completely dissolved, dropwise adding 1.78g of thionyl chloride into the system under the condition of ice-water bath at the temperature of 1 ℃, preserving heat for 0.5 hour, heating to 60 ℃, and refluxing for 6 hours;

b. adding 7.1g of triethylamine and 0.96g of hydroxylamine hydrochloride into the system under the condition of ice-water bath at the temperature of 1 ℃, preserving the temperature for 2 hours, and then heating to room temperature;

c. spin-drying the solvent on a rotary evaporator, adding 50ml of water and 2.6g of potassium carbonate, and heating to 60 ℃ for hydrolysis for 2 hours;

d. extracting the solution with ethyl acetate for 3 times, determining whether the extraction is complete by thin-layer chromatography, developing color in iodine tank, and extracting to obtain m-aminophenol.

Example two

A process method for preparing m-aminophenol comprises the following steps in sequence:

i, preparing m-cresol acetate as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₇H₈O+CH₃CClO→C₉H₁₀O₂+HCl↑

B. the preparation steps are as follows:

firstly, taking 21.6g of m-cresol into a 100ml Erlenmeyer flask, and then adding 15ml of dichloromethane into the Erlenmeyer flask to serve as a solvent; secondly, under the condition of ice-water bath at 3 ℃, 15.7g of acetyl chloride reagent is dripped into the system by a constant-pressure dropping funnel, and the reaction is carried out for 45 minutes; thirdly, continuing to react for 60 minutes at low temperature under the condition of ice-water bath at 3 ℃, then starting to heat up, controlling the temperature of the system at 60 ℃, reacting for 2.5 hours, and introducing tail gas generated by the reaction into a sodium hydroxide aqueous solution for absorption; finally, taking out a solid mixture generated after the reaction in the triangular flask, and removing unreacted solvent dichloromethane in the solid mixture by using a rotary evaporator to prepare m-toluyl acetate for later use;

II, preparing m-carboxyl phenyl acetate serving as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₉H₁₀O₂+2KMnO₄→C₉H₈O₄+2MnO₂+2KOH

B. the preparation steps are as follows:

a. taking 7.5g of m-toluyl acetate prepared in the previous step I into a 100ml triangular flask, adding 50ml of water, fully stirring, then adding 5ml of glacial acetic acid, and heating the system to 70 ℃;

b. 243g of potassium permanganate is weighed and slowly added into a m-toluyl acetate system for a plurality of times in a small amount, and after the potassium permanganate is completely added, the temperature of the system is kept at 70 ℃ for reaction for 9 hours; heating the system to 100 ℃ after purple color in the system is completely faded, reacting for 2.5 hours, measuring the pH value of the system solution to be 8 after the reaction is finished, filtering the generated solution while the solution is hot, and repeatedly washing filter cakes used in the filtering process for 3 times by using hot water after filtering for the next use;

c. regulating the pH of the filtrate prepared in the step b to be less than or equal to 1 by hydrochloric acid, keeping the solution to have no precipitate or trace precipitate, extracting by using ethyl acetate, and removing an extracting agent in the mixture by using a rotary evaporator after extraction to prepare a m-carboxyl phenyl acetate solid product for later use;

III, preparation of m-aminophenol

A. The reaction equation is as follows:

C₉H₈O₄+SOCl₂→C₉H₇ClO₃+SO₂+HCl；

C₉H₇ClO₃+NH₂OH·HCl→C₉H₉NO₄+2HCl；

B. the preparation steps are as follows:

a. get C₉H₈O₄Adding 1.73g of reagent into 15ml of ethyl acetate solution, fully stirring until the reagent is completely dissolved, dropwise adding 1.78g of thionyl chloride into the system under the condition of 3 ℃ ice-water bath, preserving heat for 1 hour, heating to 60 ℃, and refluxing for 6-8 hours;

b. adding 7.1g of triethylamine and 0.96g of hydroxylamine hydrochloride into the system under the condition of ice-water bath at the temperature of 3 ℃, preserving the temperature for 2 hours, and then heating to room temperature;

c. spin-drying the solvent on a rotary evaporator, adding 50ml of water and 2.6g of potassium carbonate, and heating to 65 ℃ for hydrolysis for 2.5 hours;

d. extracting the solution with ethyl acetate for 3 times, determining whether the extraction is complete by thin-layer chromatography, developing color in iodine tank, and extracting to obtain m-aminophenol.

EXAMPLE III

A process method for preparing m-aminophenol comprises the following steps in sequence:

i, preparing m-cresol acetate as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₇H₈O+CH₃CClO→C₉H₁₀O₂+HCl↑

B. the preparation steps are as follows:

firstly, taking 21.6g of m-cresol into a 100ml Erlenmeyer flask, and then adding 15ml of dichloromethane into the Erlenmeyer flask to serve as a solvent; secondly, under the condition of ice-water bath at 5 ℃, 15.7g of acetyl chloride reagent is dripped into the system by a constant pressure dropping funnel, and the reaction is carried out for 60 minutes; thirdly, continuing to react for 60 minutes at low temperature under the condition of ice water bath at 5 ℃, then starting to heat up, controlling the system temperature at 65 ℃, reacting for 3 hours, and introducing tail gas generated by the reaction into a sodium hydroxide aqueous solution for absorption; finally, taking out a solid mixture generated after the reaction in the triangular flask, and removing unreacted solvent dichloromethane in the solid mixture by using a rotary evaporator to prepare m-toluyl acetate for later use;

II, preparing m-carboxyl phenyl acetate serving as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₉H₁₀O₂+2KMnO₄→C₉H₈O₄+2MnO₂+2KOH

B. the preparation steps are as follows:

a. taking 7.5g of m-toluyl acetate prepared in the previous step I into a 100ml triangular flask, adding 50ml of water, fully stirring, then adding 5ml of glacial acetic acid, and heating the system to 80 ℃;

b. 243g of potassium permanganate is weighed and slowly added into a m-toluyl acetate system for a plurality of times in a small amount, and after the potassium permanganate is completely added, the temperature of the system is kept at 80 ℃ for reaction for 10 hours; after the purple color in the system is completely faded, heating the system to 110 ℃, reacting for 3 hours, measuring the pH value of the system solution to be 8.2 after the reaction is finished, filtering the generated solution while the solution is hot, and repeatedly washing a filter cake used in the filtering process for 3 times by using hot water after filtering for the next use;

c. regulating the pH of the filtrate prepared in the step b to be less than or equal to 1 by hydrochloric acid, keeping the solution to have no precipitate or trace precipitate, extracting by using ethyl acetate, and removing an extracting agent in the mixture by using a rotary evaporator after extraction to prepare a m-carboxyl phenyl acetate solid product for later use;

III, preparation of m-aminophenol

A. The reaction equation is as follows:

C₉H₈O₄+SOCl₂→C₉H₇ClO₃+SO₂+HCl；

C₉H₇ClO₃+NH₂OH·HCl→C₉H₉NO₄+2HCl；

B. the preparation steps are as follows:

a. get C₉H₈O₄Adding 1.73g of reagent into 15ml of ethyl acetate solution, fully stirring until the reagent is completely dissolved, dropwise adding 1.78g of thionyl chloride into the system under the condition of ice-water bath at 5 ℃, preserving heat for 1.5 hours, heating to 60 ℃, and refluxing for 8 hours;

b. adding 7.1g of triethylamine and 0.96g of hydroxylamine hydrochloride into the system under the condition of ice-water bath at the temperature of 5 ℃, preserving the temperature for 2 hours, and then heating to room temperature;

c. spin-drying the solvent on a rotary evaporator, adding 50ml of water and 2.6g of potassium carbonate, and heating to 70 ℃ for hydrolysis for 3 hours;

d. extracting the solution with ethyl acetate for 4 times, determining whether the extraction is complete by thin-layer chromatography, developing color in iodine tank, and extracting to obtain m-aminophenol.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (1)

1. A process method for preparing m-aminophenol is characterized by comprising the following steps in sequence:

i, preparing m-cresol acetate as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₇H₈O+CH₃CClO→C₉H₁₀O₂+HCl↑

B. the preparation steps are as follows:

firstly, taking 21.6g of m-cresol into a 100ml Erlenmeyer flask, and then adding 15ml of dichloromethane into the Erlenmeyer flask to serve as a solvent; secondly, under the condition of ice-water bath at 0-5 ℃, dropwise adding 15.7g of acetyl chloride reagent into the system by using a constant-pressure dropping funnel, and fully reacting for 30-60 minutes; thirdly, continuing to react for 60 minutes at low temperature under the condition of ice-water bath at 0-5 ℃, then starting to heat, controlling the temperature of the system at 60 +/-5 ℃, reacting for 2-3 hours, and introducing tail gas generated by the reaction into a sodium hydroxide aqueous solution for absorption; finally, taking out a solid mixture generated after the reaction in the triangular flask, and removing unreacted solvent dichloromethane in the solid mixture by using a rotary evaporator to prepare m-toluyl acetate for later use;

II, preparing m-carboxyl phenyl acetate serving as a m-aminophenol reaction raw material:

A. the reaction equation is as follows:

C₉H₁₀O₂+2KMnO₄→C₉H₈O₄+2MnO₂+2KOH

B. the preparation steps are as follows:

a. taking 7.5g of m-toluyl acetate prepared in the previous step I into a 100ml triangular flask, adding 50ml of water, fully stirring, then adding 5ml of glacial acetic acid, and heating the system to 60-80 ℃;

b. weighing 243g of potassium permanganate, slowly adding a small amount of potassium permanganate into a m-toluyl acetate system for multiple times, and keeping the system temperature at 50-80 ℃ for reacting for 8-10 hours after the potassium permanganate is completely added; after the purple color in the system is completely faded, heating the system to 90-110 ℃, reacting for 2-3 hours, determining the pH value of the system solution to be 8 +/-0.2 after the reaction is finished, filtering the generated solution while the solution is hot, and repeatedly washing a filter cake used in the filtering process for 3 times by using hot water after the filtration for the next use;

c. regulating the pH of the filtrate prepared in the step b to be less than or equal to 1 by hydrochloric acid, keeping the solution to have no precipitate or trace precipitate, extracting by using ethyl acetate, and removing an extracting agent in the mixture by using a rotary evaporator after extraction to prepare a m-carboxyl phenyl acetate solid product for later use;

III, preparation of m-aminophenol

A. The reaction equation is as follows:

C₉H₈O₄+SOCl₂→C₉H₇ClO₃+SO₂+HCl；

C₉H₇ClO₃+NH₂OH·HCl→C₉H₉NO₄+2HCl；

B. the preparation steps are as follows:

a. get C₉H₈O₄Adding 1.73g of the reagent into 15ml of ethyl acetate solution, fully stirring until the reagent is completely dissolved, dropwise adding 1.78g of thionyl chloride into the system under the condition of ice-water bath at the temperature of 0-5 ℃, preserving heat for 1 +/-0.5 hour, heating to 60 ℃, and refluxing for 6-8 hours;

b. adding 7.1g of triethylamine and 0.96g of hydroxylamine hydrochloride into the system under the condition of ice-water bath at the temperature of 0-5 ℃, preserving the temperature for 2 hours, and then heating to room temperature;

c. spin-drying the solvent on a rotary evaporator, adding 50ml of water and 2.6g of potassium carbonate, and heating to 60-70 ℃ for hydrolysis for 2-3 hours;

d. extracting the solution with ethyl acetate for 3-4 times, determining whether the extraction is complete by adopting thin-layer chromatography, developing the color in an iodine cylinder, and obtaining the finished product of m-aminophenol after the extraction is completed.