阅读说明：本技术 一种大茴香腈的生产方法 (Production method of anisyl nitrile ) 是由 牛国峰 刘淑慧 李梅香 刘博� 于 2020-12-24 设计创作，主要内容包括：本发明属于化工技术领域,尤其涉及一种大茴香腈的生产方法,包括如下步骤：1)对羟基苯甲酸与氨基甲酸酯在催化剂作用下,进行酰胺化反应,生成对羟基苯甲酰胺；2)对羟基苯甲酰胺在碳酸二甲酯中,在催化剂作用下,合成对甲氧基苯甲酰胺；3)对甲氧基苯甲酰胺在碳酸二甲酯中,在脱水剂存在下,在80～90℃下脱水3～6小时,得到大茴香腈。通过该生产方法得到的大茴香腈产品纯度高达99.4％～99.8％,大茴香腈产品的收率高达98.0％～99.2％,以对羟基苯甲酸计,反应总收率高达95.7％～98.1％,收率高,生产过程中不使用剧毒物,也无废水产生,使用溶剂安全环保易回收,原料价格低,可以实现大规模生产。(The invention belongs to the technical field of chemical industry, and particularly relates to a production method of anisyl nitrile, which comprises the following steps: 1) carrying out amidation reaction on p-hydroxybenzoic acid and carbamate under the action of a catalyst to generate p-hydroxybenzamide; 2) synthesizing p-methoxybenzamide from p-hydroxybenzamide in dimethyl carbonate under the action of a catalyst; 3) dehydrating p-methoxybenzamide in dimethyl carbonate at 80-90 ℃ for 3-6 hours in the presence of a dehydrating agent to obtain the anisyl nitrile. The purity of the anisidine product obtained by the production method is as high as 99.4-99.8%, the yield of the anisidine product is as high as 98.0-99.2%, the total reaction yield is as high as 95.7-98.1% in terms of p-hydroxybenzoic acid, the yield is high, no virulent substances are used in the production process, no waste water is generated, the used solvent is safe, environment-friendly and easy to recover, the raw material price is low, and large-scale production can be realized.)

1. The production method of the anisic nitrile is characterized by comprising the following steps:

1) carrying out amidation reaction on p-hydroxybenzoic acid and carbamate under the action of a catalyst to generate p-hydroxybenzamide;

2) synthesizing p-methoxybenzamide from p-hydroxybenzamide in dimethyl carbonate under the action of a catalyst;

3) dehydrating p-methoxybenzamide in dimethyl carbonate at 80-90 ℃ for 3-6 hours in the presence of a dehydrating agent to obtain the anisyl nitrile.

2. The method for producing anisidine of claim 1 wherein in step 1), the urethane is an alkyl carbamate.

3. The method for producing anisidine of claim 2 wherein in the step 1), the urethane is any one of methyl urethane, ethyl urethane, propyl urethane, isopropyl urethane, n-butyl urethane, octyl urethane, and isooctyl urethane.

4. The method for producing anisidine of claim 3 wherein in step 1), the urethane is methyl carbamate and the mass ratio of p-hydroxybenzoic acid to methyl carbamate is 1:0.54 to 0.8.

5. The method for producing the anisidine of claim 1 wherein in step 1), the catalyst is triethylene diamine, and the mass ratio of the p-hydroxybenzoic acid to the catalyst is 1: 0.01-0.05.

The method for producing anisidine of claim 1 wherein in step 1), the reaction temperature is 175 to 185 ℃ and the reaction time is 3 to 5 hours.

6. The method for producing anisidine of claim 1 wherein in step 2), the mass ratio of p-hydroxybenzamide to dimethyl carbonate is 1:2.8 to 5.0.

7. The method for producing the anisidine of claim 1 wherein in the step 2), the catalyst is triethylene diamine or 4-dimethylaminopyridine, and the mass ratio of the p-hydroxybenzamide to the catalyst is 1: 0.01-0.03.

8. The method for producing anisyl nitrile of claim 1, wherein in the step 2), the reaction temperature is 130 to 140 ℃ and the reaction time is 6 to 9 hours.

9. The method for producing anisidine of claim 1 wherein the mass ratio of p-methoxybenzamide to dimethyl carbonate in step 3) is 1:2.8 to 3.5.

10. The method for producing anisidine of claim 1 wherein in step 3), the dehydrating agent is thionyl chloride, and the mass ratio of p-methoxybenzamide to the dehydrating agent is 1:1.05 to 1.30.

Technical Field

The invention belongs to the technical field of chemical industry, and particularly relates to a production method of anisyl nitrile.

Background

The anisic nitrile is commonly known as p-methoxy benzonitrile, is an important novel spice, has soft and lasting fragrance and small irritation to skin, is mainly used as an organic synthetic intermediate, is an excellent raw material for blending lily of the valley, violet and lavender fragrance, and is particularly suitable for blending various essences for daily use, soap and cigarettes. At present, the production method of the anisic nitrile mainly comprises the following three methods: (1) the p-hydroxybenzoic acid method: p-hydroxybenzoic acid and dimethyl sulfate react under alkaline condition to prepare p-methoxybenzoic acid, and then react with urea and sulfamic acid to obtain the anisyl nitrile, the dimethyl sulfate is extremely toxic, and a large amount of solid waste is generated in the production process and is difficult to treat. (2) P-methoxybenzamide method: the p-methoxybenzamide is used as a raw material, and is dehydrated through the dehydration of a dehydrating agent to prepare the anisyl nitrile, and the p-methoxybenzamide is expensive and is not suitable for large-scale production. (3) P-methoxybenzaldehyde method: p-methoxybenzaldehyde is used as a raw material, and reacts with hydroxylamine hydrochloride to generate anisaldehyde oxime, and then the anisaldehyde oxime is generated after catalytic dehydration by acetic anhydride.

In addition, the anisidine product prepared by the three production methods has low purity and low yield, and is difficult to realize large-scale production. Therefore, how to overcome the above technical problems and disadvantages is a problem to be solved.

Disclosure of Invention

The aim of the invention is to overcome the defects of the prior art and provide a method for producing the anisidine, the anisidine product obtained by the method has high purity and high yield, no virulent substances are used in the production process, no wastewater is generated, the used solvent is safe, environment-friendly and easy to recover, the price of the raw material is low, and the large-scale production can be realized.

The purpose of the invention is realized as follows: a method for producing the anisic nitrile comprises the following steps:

1) carrying out amidation reaction on p-hydroxybenzoic acid and carbamate under the action of a catalyst to generate p-hydroxybenzamide;

2) synthesizing p-methoxybenzamide from p-hydroxybenzamide in dimethyl carbonate under the action of a catalyst;

3) dehydrating p-methoxybenzamide in dimethyl carbonate at 80-90 ℃ for 3-6 hours in the presence of a dehydrating agent to obtain the anisyl nitrile.

In step 1), the urethane is an alkyl carbamate, preferably any one of methyl carbamate, ethyl carbamate, propyl carbamate, isopropyl carbamate, n-butyl carbamate, octyl carbamate, and isooctyl carbamate, and more preferably methyl carbamate.

Further, in the step 1), the mass ratio of the p-hydroxybenzoic acid to the methyl carbamate is 1: 0.54-0.8.

Further, in the step 1), the catalyst is triethylene Diamine (DABCO).

Further, in the step 1), the mass ratio of the p-hydroxybenzoic acid to the catalyst is 1: 0.01-0.05.

Further, in the step 1), the reaction temperature is 175-185 ℃, and the reaction time is 3-5 hours.

Further, in the step 2), the mass ratio of the p-hydroxy benzamide to the dimethyl carbonate is 1: 2.8-5.0.

Further, in the step 2), the catalyst is triethylene Diamine (DABCO) or 4-Dimethylaminopyridine (DMAP). Further, in the step 2), the mass ratio of the p-hydroxybenzamide to the catalyst is 1: 0.01-0.03.

Further, in the step 2), the reaction temperature is 130-140 ℃, and the reaction time is 6-9 hours.

Further, in the step 3), the mass ratio of the p-methoxybenzamide to the dimethyl carbonate is 1: 2.8-3.5.

Further, in the step 3), the dehydrating agent is thionyl chloride.

Further, in the step 3), the mass ratio of the p-methoxybenzamide to the dehydrating agent is 1: 1.05-1.30.

The reaction equation in the production process is as follows:

reaction equation 1

Wherein, R is alkyl, such as methyl, ethyl, propyl, isopropyl, butyl, octyl, isooctyl and the like, preferably methyl;

reaction equation 1-1

Note: the reaction equation 1-1 is a preferred formula of the reaction equation 1;

reaction equation 2

Reaction equation 3

Compared with the prior art, the invention has the beneficial effects that:

1. the invention generates the anisidine by three steps of reaction, the first step is as follows: taking p-hydroxybenzoic acid with low price as a raw material, and reacting the p-hydroxybenzoic acid with carbamate to generate p-hydroxybenzamide under the action of a catalyst triethylene Diamine (DABCO); the second step is that: p-hydroxybenzamide is taken as a raw material and reacts with dimethyl carbonate (DMC) to generate p-methoxybenzamide under the action of a catalyst triethylene Diamine (DABCO) or 4-dimethylamino pyridine (DMAP); the third step: p-methoxybenzamide is used as a raw material, and is subjected to the action of a dehydrating agent thionyl chloride in an organic solvent dimethyl carbonate to generate the anisyl nitrile.

2. The purity of the intermediate p-hydroxybenzamide generated in the first step of the reaction is up to 99.2-99.6%, the yield is up to 97.1-98.7%, the purity of the intermediate p-methoxybenzamide generated in the second step of the reaction is up to 98.8-99.5%, the yield is up to 98.5-99.0%, the purity of the anisyl nitrile product generated in the third step of the reaction is up to 99.4-99.8%, the yield is up to 98.0-99.2%, and the total reaction yield is up to 95.7-98.1% calculated by p-hydroxybenzoic acid; it is thus understood that the intermediate products and the final products are of high purity and yield.

3. The method does not use violent poison in the production process, does not generate waste water, uses a solvent, is safe, environment-friendly and easy to recover, has low raw material price, and can realize large-scale production.

Drawings

FIG. 1 is a liquid phase diagram of p-hydroxybenzamide obtained in example 1.

FIG. 2 is a liquid phase diagram of p-methoxybenzamide obtained in example 1.

FIG. 3 is a liquid phase diagram of the anisidine obtained in example 1.

Detailed Description

The present invention will be further described with reference to the following examples.

Example 1

A method for producing the anisic nitrile comprises the following steps:

1) adding 141.0g of p-hydroxybenzoic acid, 76.1g of methyl carbamate and 2.0g of triethylene diamine into a 500ml reactor, slowly heating to 130 ℃, keeping the temperature for 30 minutes, then slowly heating to 170 ℃, reacting for 5 hours at the temperature, starting to detect the content of the p-hydroxybenzoic acid after the temperature reaches 170 ℃, and when the content of the p-hydroxybenzoic acid is lower than 0.1%, determining that the reaction is complete, and at the temperature, completing the reaction for 5 hours, wherein the product is p-hydroxybenzamide; the liquid phase shows a content of more than or equal to 99 percent. After the reaction is finished, carrying out reduced pressure distillation to recover methyl carbamate and triethylene diamine to obtain 137.0g of white parahydroxyben-zamide powder, wherein the melting point is 161 ℃, the purity is 99.6 percent (shown in figure 1) through liquid phase detection, and the yield is 97.5 percent;

2) putting 69.0g of p-hydroxybenzamide, 200.0g of dimethyl carbonate (DMC) and 1.0g of triethylene Diamine (DABCO) into a 500ml high-pressure reactor, heating to 130 ℃ (the pressure is 0.5Mpa), reacting for 9 hours at the temperature, reducing the temperature after the liquid phase monitoring reaction is completed, returning to normal pressure, recovering dimethyl carbonate and a catalyst by reduced pressure distillation to obtain 75.3g of white solid p-methoxybenzamide, the melting point is 166 ℃, the purity is 99.5% by liquid phase detection (as shown in figure 2), and the yield is 98.5%;

3) 75.3g of p-methoxybenzamide and 200ml of dimethyl carbonate are added into a 500ml reactor, the temperature is raised to 85 ℃, 79.1g of thionyl chloride is dripped within 1 hour, the reaction is carried out at 85 ℃ for 4 hours after the dripping is finished, after the reaction is finished, the dimethyl carbonate and the thionyl chloride are recovered by reduced pressure distillation, 65.8g of white solid anisyl nitrile is obtained, the melting point is 58 ℃, the purity is 99.7 percent (shown in figure 3) through liquid phase detection, and the yield is 98.9 percent.

The total yield was 95.8% based on p-hydroxybenzoic acid.

Example 2

A method for producing the anisic nitrile comprises the following steps:

1) 139.6g of p-hydroxybenzoic acid, 90.7g of methyl carbamate and 4.2g of triethylene diamine are added into a 500ml reactor, the temperature is slowly increased to 130 ℃, the temperature is kept for 30 minutes, then the temperature is slowly increased to 180 ℃, the reaction is carried out for 4 hours at the temperature, the content of the p-hydroxybenzoic acid is detected after the temperature reaches 180 ℃, when the content of the p-hydroxybenzoic acid is lower than 0.1 percent, the reaction is considered to be complete, at the temperature, the reaction is finished within 4 hours, and the product is p-hydroxybenzamide; the liquid phase shows a content of more than or equal to 99 percent. After the reaction is finished, decompressing and distilling to recover methyl carbamate and triethylene diamine to obtain white parahydroxyben-zamide powder of 137.5g, the melting point is 161 ℃, the purity is 99.5 percent and the yield is 98.7 percent through liquid phase detection;

2) 70.3g of p-hydroxybenzamide, 281.2g of dimethyl carbonate (DMC) and 1.4g of 4-Dimethylaminopyridine (DMAP) are put into a 500ml high-pressure reactor, the temperature is raised to 135 ℃ (the pressure is 0.4Mpa), the reaction is carried out for 7 hours at the temperature, the temperature is reduced after the liquid phase monitoring reaction is completed, the reaction is returned to normal pressure, the dimethyl carbonate and the catalyst are recovered by reduced pressure distillation, 77.2g of white solid p-methoxybenzamide is obtained, the melting point is 165 ℃, the purity is 99.4 percent and the yield is 99.0 percent through liquid phase detection;

3) 77.2g of p-methoxybenzamide and 231ml of dimethyl carbonate are added into a 500ml reactor, the temperature is raised to 80 ℃, 88.8g of thionyl chloride is dripped within 1 hour, the reaction is carried out at 80 ℃ for 6 hours after the dripping is finished, after the reaction is finished, the dimethyl carbonate and the thionyl chloride are recovered by reduced pressure distillation, 67.6g of white solid anisyl nitrile is obtained, the melting point is 58 ℃, the purity is 99.8 percent through liquid phase detection, and the yield is 99.2 percent.

The total yield was 98.1% based on p-hydroxybenzoic acid.

Example 3

A method for producing the anisic nitrile comprises the following steps:

1) 138.2g of p-hydroxybenzoic acid, 110.6g of methyl carbamate and 6.9g of triethylene diamine are added into a 500ml reactor, the temperature is slowly increased to 130 ℃, the temperature is kept for 30 minutes, then the temperature is slowly increased to 190 ℃, the reaction is carried out for 3 hours at the temperature, the content of the p-hydroxybenzoic acid is detected after the temperature reaches 190 ℃, when the content of the p-hydroxybenzoic acid is lower than 0.1 percent, the reaction is considered to be complete, and at the temperature, the reaction is completed within 3 hours, and the product is p-hydroxybenzamide; the liquid phase shows a content of more than or equal to 99 percent. After the reaction is finished, carrying out reduced pressure distillation to recover methyl carbamate and triethylene diamine to obtain 134.3g of white parahydroxybenzamide powder, wherein the melting point is 162 ℃, the purity is 99.2% and the yield is 97.1% by liquid phase detection;

2) 70.6g of p-hydroxybenzamide, 353.0g of dimethyl carbonate (DMC) and 2.1g of triethylene Diamine (DABCO) are put into a 500ml high-pressure reactor, the temperature is raised to 140 ℃ (the pressure is 0.35Mpa), the reaction is carried out for 6 hours at the temperature, the temperature is reduced after the liquid phase monitoring reaction is completed, the reaction is returned to normal pressure, the dimethyl carbonate and the catalyst are recovered by reduced pressure distillation, 77.6g of white solid p-methoxybenzamide is obtained, the melting point is 165 ℃, the purity is 98.8 percent and the yield is 98.5 percent through liquid phase detection;

3) 77.6g of p-methoxybenzamide and 254ml of dimethyl carbonate are added into a 500ml reactor, the temperature is raised to 90 ℃, 100.9g of thionyl chloride is dripped within 1 hour, the reaction is carried out at 90 ℃ for 3 hours after the dripping is finished, after the reaction is finished, the dimethyl carbonate and the thionyl chloride are recovered by reduced pressure distillation, 67.4g of white solid anisyl nitrile is obtained, the melting point is 59 ℃, the purity is 99.4 percent through liquid phase detection, and the yield is 98.0 percent.

The total yield was 95.7% based on p-hydroxybenzoic acid.

The data of the above examples 1 to 3 show that the purity of the anisidine product obtained by the production method is as high as 99.4-99.8%, the yield of the anisidine product is as high as 98.0-99.2%, the total reaction yield is as high as 95.7-98.1% in terms of p-hydroxybenzoic acid, the yield is high, no toxic substances are used in the production process, no wastewater is generated, the solvent is used, the solvent is safe, environment-friendly and easy to recover, the raw material price is low, and the large-scale production can be realized.