阅读说明：本技术 一种催化对硝基氯苯氨解制备对硝基苯胺的方法 (Method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene ) 是由 周春松 于 2021-09-22 设计创作，主要内容包括：本发明公开了一种催化对硝基氯苯氨解制备对硝基苯胺的方法,包括以下步骤：制备多孔氧化锌；将聚苯乙烯颗粒、多孔氧化锌和氯苯与二甲亚砜的混合溶剂搅拌混合处理,制得纺丝液,静电纺丝处理后制得掺杂多孔氧化锌的多孔聚苯乙烯纤维；将掺杂多孔氧化锌的多孔聚苯乙烯纤维置于四氢呋喃中溶胀,然后过滤,溶胀后的材料和聚乙二醇、四丁基氯化铵、氢氧化钠溶液混合搅拌,升温反应,制得催化剂；将上述制得的催化剂和对硝基苯胺和液氨混合加入到高压反应釜内,升温反应,反应结束后趁热过滤,得到的液体进行冷却结晶,之后过滤,过滤得到的固体干燥后,制得对硝基苯胺。该方法将相转移催化剂固载化,改善了催化剂的稳定性,便于回收。(The invention discloses a method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene, which comprises the following steps: preparing porous zinc oxide; stirring and mixing polystyrene particles, porous zinc oxide, chlorobenzene and a mixed solvent of dimethyl sulfoxide to prepare a spinning solution, and performing electrostatic spinning to prepare porous polystyrene fibers doped with porous zinc oxide; placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran for swelling, then filtering, mixing and stirring the swollen material with polyethylene glycol, tetrabutylammonium chloride and sodium hydroxide solution, and heating for reaction to obtain a catalyst; mixing the prepared catalyst, p-nitroaniline and liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating for reaction, filtering while the mixture is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to prepare the p-nitroaniline. The method can immobilize the phase transfer catalyst, improve the stability of the catalyst and facilitate the recovery.)

1. A method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene is characterized by comprising the following steps:

(1) dissolving zinc acetate in ethanol to prepare a zinc acetate solution, then slowly adding the ethanol solution of oxalic acid and dodecyl trimethyl ammonium bromide, stirring, mixing and reacting, drying the prepared colloidal solution, and then calcining to prepare porous zinc oxide;

(2) stirring and mixing polystyrene particles, porous zinc oxide, chlorobenzene and a mixed solvent of dimethyl sulfoxide to prepare a spinning solution, and performing electrostatic spinning to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran for swelling, then filtering, mixing and stirring the swollen material with polyethylene glycol 400, tetrabutylammonium chloride and sodium hydroxide solution, heating for reaction, cooling to room temperature after the reaction is finished, filtering, washing the obtained precipitate, drying, then performing Soxhlet extraction by using tetrahydrofuran as an extractant, and drying to obtain a catalyst;

(4) mixing the prepared catalyst, p-nitroaniline and liquid ammonia, adding into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 8-9 h, filtering while the reaction is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

2. The method for preparing p-nitroaniline by catalytic ammonolysis of p-nitrochlorobenzene according to claim 1, wherein in step (1), the concentration of the zinc acetate solution is 0.1mmol/ml, the concentration of the oxalic acid in the ethanol solution is 6.25 wt%, and the volume ratio of the two is 5: (1.5-2); the addition amount of the dodecyl trimethyl ammonium bromide is 3-5 wt% of the mass of the zinc acetate.

3. The method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene according to claim 1, wherein in the step (1), the temperature of the stirring and mixing reaction is 60 ℃, and the reaction time is 2-3 h; the drying temperature is 80-90 ℃ and the drying time is 20-24 h.

4. The method for preparing p-nitroaniline by catalytic ammonolysis of p-nitrochlorobenzene according to claim 1, wherein in step (1), the calcination temperature is 480-520 ℃, the calcination time is 1.5-2.5 h, and the calcination atmosphere is air.

5. The method for preparing p-nitroaniline by catalytic ammonolysis of p-nitrochlorobenzene according to claim 1, wherein in the step (2), the volume ratio of chlorobenzene to dimethyl sulfoxide is 3: 7, the mass concentration of the polystyrene particles in the spinning solution is 25-35 wt%, and the mass concentration of the porous zinc oxide is 5-8 wt%.

6. The method for preparing p-nitroaniline by catalytic ammonolysis of p-nitrochlorobenzene according to claim 1, wherein in the step (2), the temperature of the stirring and mixing treatment is 50 ℃ and the time is 10-15 h.

7. The method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene according to claim 1, wherein in the step (2), the electrostatic spinning conditions are as follows: collecting by using a rotary collector, wherein the distance between the rotary collector and the needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV.

8. The method for preparing p-nitroaniline by catalytic ammonolysis of p-nitrochlorobenzene according to claim 1, wherein in the step (3), the swelling time is 20-24 h.

9. The method for preparing p-nitroaniline by catalytic ammonolysis of p-nitrochlorobenzene according to claim 1, wherein in step (3), the concentration of the sodium hydroxide solution is 30 wt%, and the dosage ratio of the porous zinc oxide-doped porous polystyrene fiber, the polyethylene glycol 400, the tetrabutylammonium chloride and the sodium hydroxide solution is 5 g: (18-22) g: (1-2) g: 100 ml.

10. The method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene according to claim 1, wherein in the step (3) and in the step (4), the mass ratio of the catalyst to the p-nitroaniline to the liquid ammonia is 30: (31-33): 60.

Technical Field

The invention relates to the field of organic synthesis, in particular to a method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene.

Background

Para-nitroaniline is an important organic chemical raw material, can be used as an intermediate of an anti-aging agent, a dye, a pesticide and a veterinary drug, is mainly used for preparing para-phenylenediamine for synthesizing aramid fiber, and the para-phenylenediamine is a novel high-tech synthetic fiber, so that the demand on para-nitroaniline is kept to be rapidly increased along with the production of an aramid fiber project in the coming years. The existing method for preparing p-nitroaniline mainly takes p-nitrochlorobenzene and ammonia water as raw materials, and the product is prepared under the catalysis of a phase transfer catalyst. The phase transfer catalyst can dissolve or extract inorganic ions and organic ions into the organic phase in the form of ion pairs, thereby accelerating reactions that are difficult or impossible to carry out due to phase boundary isolation. Although these studies have made some progress, there are problems such as poor stability of the catalyst, toxicity or inability to recycle it.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the defects in the prior art, the method for preparing the paranitroaniline by catalyzing the ammonolysis of the paranitrochlorobenzene is provided, and the method carries the phase transfer catalyst, improves the stability of the catalyst and is convenient to recycle.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a method for preparing p-nitroaniline by catalyzing aminolysis of p-nitrochlorobenzene comprises the following steps:

(1) dissolving zinc acetate in ethanol to prepare a zinc acetate solution, then slowly adding the ethanol solution of oxalic acid and dodecyl trimethyl ammonium bromide, stirring, mixing and reacting, drying the prepared colloidal solution, and then calcining to prepare porous zinc oxide;

(2) stirring and mixing polystyrene particles, porous zinc oxide, chlorobenzene and a mixed solvent of dimethyl sulfoxide to prepare a spinning solution, and performing electrostatic spinning to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran for swelling, then filtering, mixing and stirring the swollen material with polyethylene glycol 400, tetrabutylammonium chloride and sodium hydroxide solution, heating for reaction, cooling to room temperature after the reaction is finished, filtering, washing the obtained precipitate, drying, then performing Soxhlet extraction by using tetrahydrofuran as an extractant, and drying to obtain a catalyst;

(4) mixing the prepared catalyst, p-nitroaniline and liquid ammonia, adding into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 8-9 h, filtering while the reaction is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

Preferably, in the step (1), the concentration of the zinc acetate solution is 0.1mmol/ml, the concentration of the oxalic acid ethanol solution is 6.25 wt%, and the volume ratio of the two is 5: (1.5-2); the addition amount of the dodecyl trimethyl ammonium bromide is 3-5 wt% of the mass of the zinc acetate.

Preferably, in the step (1), the temperature of the stirring and mixing reaction is 60 ℃, and the reaction time is 2-3 h; the drying temperature is 80-90 ℃ and the drying time is 20-24 h.

Preferably, in the step (1), the calcination temperature is 480-520 ℃, the calcination time is 1.5-2.5 h, and the atmosphere during calcination is air.

Preferably, in the step (2), the volume ratio of chlorobenzene to dimethyl sulfoxide is 3: 7, the mass concentration of the polystyrene particles in the spinning solution is 25-35 wt%, and the mass concentration of the porous zinc oxide is 5-8 wt%.

Preferably, in the step (2), the temperature of the stirring and mixing treatment is 50 ℃ and the time is 10-15 h.

Preferably, in the step (2), the electrostatic spinning conditions are as follows: collecting by using a rotary collector, wherein the distance between the rotary collector and the needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV.

Preferably, in the step (3), the swelling time is 20-24 h; the concentration of the sodium hydroxide solution is 30 wt%, and the dosage ratio of the porous polystyrene fiber doped with the porous zinc oxide, the polyethylene glycol 400, the tetrabutylammonium chloride and the sodium hydroxide solution is 5 g: (18-22) g: (1-2) g: 100 ml.

Preferably, in the step (4), the mass ratio of the catalyst, the paranitroaniline and the liquid ammonia is 30: (31-33): 60.

due to the adoption of the technical scheme, the invention has the beneficial effects that:

according to the invention, dodecyl trimethyl ammonium bromide is used as a pore-forming agent to prepare porous zinc oxide, the particle size of the prepared porous zinc oxide is 30-40 nm, the average pore size is 3-5 nm, the porous zinc oxide and polystyrene particles are added into an organic solvent for electrostatic spinning, the proportion of chlorobenzene and dimethyl sulfoxide is effectively controlled, during spinning, the chlorobenzene is used as a solvent, and the dimethyl sulfoxide is used as a non-solvent, during spinning, the solvent is evaporated, but the non-solvent causes phase separation, the solvent is evaporated in a large amount to increase the proportion of the dimethyl sulfoxide, and the solvent is evaporated to condense water to form water, so that the dimethyl sulfoxide is dissolved, the phase separation is accelerated, and larger pores are generated on the surface of a fiber. The porous zinc oxide doped polystyrene fiber prepared by the invention has the diameter of 5-7 mu m, the average pore size of 50-80 nm, good mechanical property and tensile strength of up to 3.5 MPa.

The invention uses self-made porous zinc oxide doped porous polystyrene fiber/polyethylene glycol as a carrier, and loads tetrabutylammonium bromide to prepare the three-phase transfer catalyst, which has good stability and high catalytic activity, can be separated from the product by simple filtration, and can be repeatedly used.

Detailed Description

The invention is further illustrated by the following examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Example 1

(1) Dissolving zinc acetate in ethanol to prepare 500ml of zinc acetate solution with the concentration of 0.1mmol/ml, slowly adding 200ml of ethanol solution of 6.25 wt% oxalic acid and 0.54g of dodecyl trimethyl ammonium bromide, stirring and mixing at 60 ℃, reacting for 2 hours, drying the prepared colloidal solution at 80 ℃ for 20 hours, and then placing the colloidal solution in a muffle furnace in air atmosphere, calcining at 480 ℃ for 1.5 hours, thus preparing porous zinc oxide;

(2) stirring and mixing 30g of polystyrene particles, 8g of porous zinc oxide, 30ml of chlorobenzene and 70ml of dimethyl sulfoxide at 50 ℃ for 10 hours to prepare spinning solution, carrying out electrostatic spinning on the spinning solution, collecting the spinning solution by using a rotary collector during spinning, wherein the distance between the rotary collector and a needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV; drying the fibers after electrostatic spinning treatment to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran to swell for 20 hours, then filtering, mixing and stirring 5g of swollen macroporous polystyrene material, 18g of polyethylene glycol 400, 1g of tetrabutylammonium chloride and 100ml of 30 wt% sodium hydroxide solution, heating to 70 ℃ to react for 3 hours, cooling to room temperature after the reaction is finished, filtering, washing the obtained precipitate, drying, then performing Soxhlet extraction by using tetrahydrofuran as an extracting agent, and drying to obtain a catalyst;

(4) and mixing 30g of the prepared catalyst, 31g of p-nitroaniline and 60g of liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 8 hours, filtering while the reaction is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

Example 2

(1) Dissolving zinc acetate in ethanol to prepare 500ml of zinc acetate solution with the concentration of 0.1mmol/ml, slowly adding 200ml of ethanol solution of 6.25 wt% oxalic acid and 0.54g of dodecyl trimethyl ammonium bromide, stirring and mixing at 60 ℃, reacting for 3 hours, drying the prepared colloidal solution at 80 ℃ for 24 hours, and then placing the colloidal solution in a muffle furnace in air atmosphere and calcining at 520 ℃ for 1.5 hours to prepare porous zinc oxide;

(2) stirring and mixing 30g of polystyrene particles, 8g of porous zinc oxide, 30ml of chlorobenzene and 70ml of dimethyl sulfoxide at 50 ℃ for 15h to prepare spinning solution, carrying out electrostatic spinning on the spinning solution, collecting the spinning solution by using a rotary collector during spinning, wherein the distance between the rotary collector and a needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV; drying the fibers after electrostatic spinning treatment to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran to swell for 20 hours, then filtering, mixing and stirring 5g of swollen macroporous polystyrene material, 22g of polyethylene glycol 400, 1g of tetrabutylammonium chloride and 100ml of 30 wt% sodium hydroxide solution, heating to 70 ℃ to react for 5 hours, cooling to room temperature after the reaction is finished, filtering, washing and drying the obtained precipitate, then performing Soxhlet extraction by using tetrahydrofuran as an extracting agent, and drying to obtain a catalyst;

(4) and mixing 30g of the prepared catalyst, 31.5g of p-nitroaniline and 60g of liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 9 hours, filtering while the mixture is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

Example 3

(1) Dissolving zinc acetate in ethanol to prepare 500ml of zinc acetate solution with the concentration of 0.1mmol/ml, slowly adding 200ml of ethanol solution of 6.25 wt% oxalic acid and 0.54g of dodecyl trimethyl ammonium bromide, stirring and mixing at 60 ℃, reacting for 2.5 hours, drying the prepared colloidal solution at 80 ℃ for 21 hours, and then placing the colloidal solution in a muffle furnace in air atmosphere and calcining at 500 ℃ for 2 hours to prepare porous zinc oxide;

(2) stirring and mixing 30g of polystyrene particles, 8g of porous zinc oxide, 30ml of chlorobenzene and 70ml of dimethyl sulfoxide at 50 ℃ for 11h to prepare spinning solution, carrying out electrostatic spinning on the spinning solution, collecting the spinning solution by using a rotary collector during spinning, wherein the distance between the rotary collector and a needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV; drying the fibers after electrostatic spinning treatment to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran to swell for 24 hours, then filtering, mixing and stirring 5g of swollen macroporous polystyrene material, 20g of polyethylene glycol 400, 1.5g of tetrabutylammonium chloride and 100ml of 30 wt% sodium hydroxide solution, heating to 70 ℃ to react for 4 hours, cooling to room temperature after the reaction is finished, filtering, washing the obtained precipitate, drying, then performing Soxhlet extraction by using tetrahydrofuran as an extracting agent, and drying to obtain a catalyst;

(4) and mixing 30g of the prepared catalyst, 31.5g of p-nitroaniline and 60g of liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 8 hours, filtering while the mixture is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

Example 4

(1) Dissolving zinc acetate in ethanol to prepare 500ml of zinc acetate solution with the concentration of 0.1mmol/ml, slowly adding 200ml of ethanol solution of 6.25 wt% oxalic acid and 0.54g of dodecyl trimethyl ammonium bromide, stirring and mixing at 60 ℃, reacting for 2 hours, drying the prepared colloidal solution at 90 ℃ for 23 hours, and then placing the colloidal solution in a muffle furnace in an air atmosphere and calcining at 500 ℃ for 2 hours to prepare porous zinc oxide;

(2) stirring and mixing 30g of polystyrene particles, 8g of porous zinc oxide, 30ml of chlorobenzene and 70ml of dimethyl sulfoxide at 50 ℃ for 13h to prepare spinning solution, carrying out electrostatic spinning on the spinning solution, collecting the spinning solution by using a rotary collector during spinning, wherein the distance between the rotary collector and a needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV; drying the fibers after electrostatic spinning treatment to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran to swell for 24 hours, then filtering, mixing and stirring 5g of swollen macroporous polystyrene material, 20g of polyethylene glycol 400, 2g of tetrabutylammonium chloride and 100ml of 30 wt% sodium hydroxide solution, heating to 70 ℃ to react for 4 hours, cooling to room temperature after the reaction is finished, filtering, washing and drying the obtained precipitate, then performing Soxhlet extraction by using tetrahydrofuran as an extracting agent, and drying to obtain a catalyst;

(4) and mixing 30g of the prepared catalyst, 31.5g of p-nitroaniline and 60g of liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 9 hours, filtering while the mixture is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

Example 5

(1) Dissolving zinc acetate in ethanol to prepare 500ml of zinc acetate solution with the concentration of 0.1mmol/ml, slowly adding 200ml of ethanol solution of 6.25 wt% oxalic acid and 0.54g of dodecyl trimethyl ammonium bromide, stirring and mixing at 60 ℃, reacting for 3 hours, drying the prepared colloidal solution at 90 ℃ for 24 hours, and then placing the colloidal solution in a muffle furnace in an air atmosphere and calcining at 500 ℃ for 2.5 hours to prepare porous zinc oxide;

(2) stirring and mixing 30g of polystyrene particles, 8g of porous zinc oxide, 30ml of chlorobenzene and 70ml of dimethyl sulfoxide at 50 ℃ for 15h to prepare spinning solution, carrying out electrostatic spinning on the spinning solution, collecting the spinning solution by using a rotary collector during spinning, wherein the distance between the rotary collector and a needle point is 15cm, the feeding speed during electrostatic spinning is 0.5ml/h, and the spinning voltage is 10 KV; drying the fibers after electrostatic spinning treatment to prepare porous polystyrene fibers doped with porous zinc oxide;

(3) placing porous polystyrene fiber doped with porous zinc oxide in tetrahydrofuran to swell for 24 hours, then filtering, mixing and stirring 5g of swollen macroporous polystyrene material, 20g of polyethylene glycol 400, 2g of tetrabutylammonium chloride and 100ml of 30 wt% sodium hydroxide solution, heating to 70 ℃ to react for 5 hours, cooling to room temperature after the reaction is finished, filtering, washing and drying the obtained precipitate, then performing Soxhlet extraction by using tetrahydrofuran as an extracting agent, and drying to obtain a catalyst;

(4) and mixing 30g of the prepared catalyst, 31.5g of p-nitroaniline and 60g of liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 8 hours, filtering while the mixture is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

Comparative example

Mixing 2.22g of tetrabutylammonium chloride, 31.5g of p-nitroaniline and 60g of liquid ammonia, adding the mixture into a high-pressure reaction kettle, heating to 170 ℃ for reaction for 8 hours, filtering while the mixture is hot after the reaction is finished, cooling and crystallizing the obtained liquid, filtering, and drying the filtered solid to obtain the p-nitroaniline.

The yields and purities of p-nitroanilines obtained in the above examples and comparative examples are shown in Table 1.

TABLE 1

	Yield and content of	Purity%
			Example 1	98.9	99.9
Example 2	99.2	99.9
			Example 3	98.9	99.9
Example 4	99.0	99.9
			Example 5	99.2	99.9
Comparative example	97.3	99.9

From the test results, the prepared catalyst has higher catalytic activity after the phase transfer catalyst is immobilized, and the yield of the product is effectively improved.

Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.