CN115057844A - A kind of preparation method of chlorantraniliprole - Google Patents

Abstract

The invention discloses a preparation method of chlorantraniliprole. The method uses 3-bromo-1-(pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (I) as a raw material , 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide shown in (II) is obtained by simultaneous oxidation with acyl bromination reagent, 3- Bromine-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide (II) and 2-amino-5-chloro-N,3-dimethylbenzamide (III) reaction to obtain high-content chlorantraniliprole (IV), the method is simple and safe to operate, has little damage to equipment, high yield, avoids the production of specific impurities (VI), and is suitable for industrialized production.

Description

A kind of preparation method of chlorantraniliprole

technical field

The invention relates to the field of pesticides and insecticides, in particular to a preparation method of chlorantraniliprole.

Background technique

Chlorantranili-pole is a new type of efficient, highly active and safe insecticide, the chemical name is 3-bromo-N-{4-chloro-2-methyl-6-[(methyl) Amino)carbonyl]phenyl}-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxamide, it can effectively control almost all lepidopteran pests and some other pests, and its efficient The larvicidal activity and persistence of efficacy provide outstanding crop protection.

The synthesis of the chlorantraniliprole reported in the patent at present adopts thionyl chloride as the oxidative acyl chloride reagent, and the production process of impurity (VI) is shown in the following reaction:

This reaction produces intermediate (V) in which bromine atoms are replaced by chlorine atoms, which is further converted into impurity (VI), which is an impurity that needs to be strictly controlled in the chlorantraniliprole product. In order to suppress the generation of impurity (VI), patent CN110028489A discloses a method for preparing chlorantraniliprole by a decompression method, the method rapidly removes the hydrogen chloride generated in the reaction by decompression method, and reduces the amount of bromine atoms substituted by chlorine atoms. Probability, when the reaction is at the scale of 100 grams, the content of impurity (VI) can be controlled within 0.3wt% to 0.4wt%, if this scheme is not adopted, the content of impurity (VI) is within 7.1wt% to 13.3wt% between. However, it was found in the experiment that this method has the following problems: 1. Since the reaction generates a large amount of hydrogen chloride and sulfur dioxide, it will seriously corrode the vacuum pump and other equipment that provides negative pressure; The content of impurity (VI) will still seriously exceed the standard (more than 1.5wt%, product requirements are less than 0.3wt%); 3. The negative pressure reaction system is prone to bumping, and there is a safety risk of punching materials.

Based on the above problems, it is urgent to develop a synthetic method with better selectivity, safety and economy, which can produce chlorantraniliprole with the content of impurity (VI) meeting the product requirements under normal pressure.

SUMMARY OF THE INVENTION

的含量。The object of the present invention is to provide a kind of preparation method of chlorantraniliprole, thereby reducing impurities in the final product

content.

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

The invention provides a preparation method of chlorantraniliprole: under normal pressure, 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5 -formic acid reacts with acyl bromination reagent to give 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide, the 3-bromo-1-(3-chloro- 2-Pyridyl)-1H-pyrazole-5-formyl bromide is reacted with 2-amino-5-chloro-N,3-dimethylbenzamide to obtain the chlorantraniliprole.

Preferably, the acyl bromide reagent is one or more of sulfoxide dibromide, phosphorus tribromide or phosphorus pentabromide,

的同时，保证了所述3-溴-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酰溴的反应收率和纯度。Further preferably, the acyl bromination reagent is sulfoxide dibromide, which avoids generating

At the same time, the reaction yield and purity of the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide are guaranteed.

Preferably, the molar ratio of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid to the acyl bromination reagent is 1 : 2 to 5.

Preferably, the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid is reacted with the acid bromination reagent in the presence of a solvent , the temperature of the reaction is controlled to be between 0°C and the boiling point of the solvent.

Preferably, the time for controlling the reaction of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid with the acid bromination reagent is 1 to 10 hours.

Under the synergistic effect of the above reaction parameters, the preparation yield of the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide is improved.

Further preferably, the temperature of the reaction of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the acid bromination reagent is controlled is a temperature between 30°C and the boiling point of the solvent.

Further preferably, the time of controlling the reaction of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the acyl bromination reagent 2 to 5 hours.

More preferably, control the reaction of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the acyl bromination reagent The time is 2 to 3 hours.

Further preferably, the reaction solvent of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the acyl bromination reagent is acetonitrile , one or more of toluene, chlorobenzene, dichloroethane and xylene.

Further preferably, the mass ratio of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid to the solvent is 1:1 ~10.

Further preferably, the mass ratio of described 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and described solvent is 1: 2 to 5.

By controlling the reaction temperature, the molar ratio of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid to the acid bromide reagent , the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the solvent's mass ratio, reaction times, solvent selection, The reaction of the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide has better selectivity, and the 3-bromo-1- Reaction yield of (3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide.

Preferably, the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-dimethyl The benzamide is reacted in the presence of a solvent, and the temperature of the reaction is controlled to be a temperature between 0°C and the boiling point of the solvent.

Preferably, the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-dimethyl bromide are controlled The reaction time of the benzamide is 0.5 to 10 hours.

Under the synergistic effect of the above reaction parameters, the preparation yield of the chlorantraniliprole is improved.

Further preferably, control the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-di The temperature of the reaction of the methylbenzamide is between 50°C and the boiling point of the solvent.

Further preferably, control the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-di The reaction time of toluamide is 1 to 2 hours.

More preferably, control the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3- The reaction time of dimethylbenzamide is 1 to 1.5 hours.

Further preferably, the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-dimethyl The reaction solvent of the benzamide is one or more of acetonitrile, toluene, chlorobenzene, dichloroethane, xylene, and cyclohexane.

Further preferably, the mass ratio of the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide to the solvent is 1:1-5.

Wherein, the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-dimethyl The 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide can also be put into the solvent to prepare 3 -Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide solution, then the 2-amino-5-chloro-N,3-dimethylbenzamide Throw it into the solvent to obtain 2-amino-5-chloro-N,3-dimethylbenzamide solution, 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5 -Formyl bromide solution and 2-amino-5-chloro-N,3-dimethylbenzamide solution are mixed and reacted.

More preferably, when preparing the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide solution, the 3-bromo-1-(3-chloro -2-pyridyl)-1H-pyrazole-5-formyl bromide and the solvent have a mass ratio of 1:1-2.

By controlling the reaction temperature, the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-di The molar ratio of feed intake of methyl benzamide, the feed intake mass ratio of described 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and described solvent, the reaction time , solvent selection, further improve the reaction yield of the chlorantraniliprole.

Wherein, the reaction solvent of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the acid bromination reagent is the same as the Reaction of 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide with the 2-amino-5-chloro-N,3-dimethylbenzamide The solvent may be the same or different. Preferably, the reaction solvent of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the acyl bromination reagent is the same as the The combination of the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3-dimethylbenzamide The reaction solvent is the same.

The preparation method of described chlorantraniliprole is as follows:

The 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the solvent were added to the reactor, and the Acyl bromide reagent, continue the incubation reaction after the dropwise addition. After the reaction, the solvent was evaporated to dryness by distillation under reduced pressure to obtain the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide. Dissolve the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide in a solvent to obtain 3-bromo-1-(3-chloro-2-pyridyl )-1H-pyrazole-5-formyl bromide solution.

The 2-amino-5-chloro-N,3-dimethylbenzamide and the solvent were added to the reactor, and the 3-bromo-1-(3-chloro-2-pyridine was added dropwise at the reaction temperature base)-1H-pyrazole-5-formyl bromide solution, continue the incubation reaction after the dropwise addition. After the reaction is completed, the chlorantraniliprole is obtained through cooling, filtration, rinsing and drying;

Wherein, the molar ratio of controlling the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid to the acyl bromination reagent is 1 : 2 to 10, control the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3- The molar ratio of dimethylbenzamide is 1:0.8～1.2.

Compared with the prior art, the present invention has the following advantages:

的生成，使氯虫苯甲酰胺的产品品质更高。同时，该工艺无需减压操作，减少了设备腐蚀、消除了冲料风险，使氯虫苯甲酰胺的制备过程更加安全、环保，适合大规模工业化生产。The preparation method of chlorantraniliprole provided by the invention avoids impurities

The formation of chlorantraniliprole makes the product quality of chlorantraniliprole higher. At the same time, the process does not require decompression operation, reduces equipment corrosion, eliminates the risk of material flushing, and makes the preparation process of chlorantraniliprole more safe and environmentally friendly, and is suitable for large-scale industrial production.

Detailed ways

The present invention will be further described below in conjunction with the examples. However, the present invention is not limited to the following examples. The implementation conditions adopted in the examples can be further adjusted according to different requirements of specific use, and the unremarked implementation conditions are the conventional conditions in the industry. The technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.

的含量得到控制。该反应只需在常压下进行，无需对设备进行减压操作，减少了设备的腐蚀、消除了冲料的风险，使氯虫苯甲酰胺的制备过程更加安全、环保。Under normal pressure, 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid was reacted with an acid bromide reagent to obtain 3-bromo-1 -(3-Chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide, followed by 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-methan Acyl bromide reacts with 2-amino-5-chloro-N,3-dimethylbenzamide to give chlorantraniliprole. Through the above reaction design, the impurities in the final product are

content is controlled. The reaction only needs to be carried out under normal pressure, and no decompression operation of the equipment is required, the corrosion of the equipment is reduced, the risk of material flushing is eliminated, and the preparation process of chlorantraniliprole is safer and more environmentally friendly.

Describe the scheme of the present invention in detail below in conjunction with embodiment:

Example 1

In a 1000 mL reaction flask, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (94.2 g, 97%, 0.3 mol) , 282.6 g of acetonitrile. Sulfoxide dibromide (249.4 g, 1.2 mol) was slowly added dropwise at 30° C. After the dropwise addition, the reaction was continued for 2 hours, and the acetonitrile solvent was evaporated to dryness by distillation under reduced pressure to obtain a reddish-brown oily 3-bromo-1-( 3-Chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide 115 g. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide was dissolved in 120 g of acetonitrile and used directly in the next reaction.

未检出，氯虫苯甲酰胺的定量含量为96.5％，上述两步的收率为83.6％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 1000 mL reaction flask, 2-amino-5-chloro-N,3-dimethylbenzamide (60.0 g, 96%, 0.29 mol) and 180 g of acetonitrile were added, and the temperature was raised to reflux. The acetonitrile solution of the above-mentioned 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide was slowly added dropwise to the reaction flask, and the reaction was continued for 1 hour after the dropwise addition. Then, it was cooled to room temperature, filtered, rinsed and dried to obtain 125.7 g of off-white solid chlorantraniliprole. impurities

Not detected, the quantitative content of chlorantraniliprole was 96.5%, and the yield of the above two steps was 83.6% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydrogen -1H-pyrazole-5-carboxylic acid).

Example 2

In a 1000 mL reaction flask, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (79.3 g, 96%, 0.25 mol) , 237.9 g of toluene. Slowly add sulfoxide dibromide (259.8 g, 1.25 mol) dropwise at 50°C, continue the reaction for 2 hours after the dropwise addition, and evaporate the toluene solvent by vacuum distillation to obtain a reddish-brown oily 3-bromo-1-( 3-Chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide 97 g. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide was dissolved in 100 g of toluene and used directly in the next reaction.

未检出，氯虫苯甲酰胺的定量含量为96.0％，上述两步的收率为85.0％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 1000 mL reaction flask, 2-amino-5-chloro-N,3-dimethylbenzamide (55.9 g, 96%, 0.27 mol) and 112 g of toluene were added, and the temperature was raised to reflux. The toluene solution of the above-mentioned 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide was slowly added dropwise to the reaction flask, and the reaction was continued for 1 hour after the dropwise addition was completed. Then cooled to room temperature, filtered, rinsed, and dried to obtain 106.9 g of off-white solid chlorantraniliprole, impurity

Not detected, the quantitative content of chlorantraniliprole was 96.0%, and the yield of the above two steps was 85.0% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydrogen -1H-pyrazole-5-carboxylic acid).

Example 3

In a 1000 mL reaction flask, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (64.1 g, 95%, 0.20 mol) , 320 g of 1,2-dichloroethane. Sulfoxide dibromide (103.9 g, 0.5 mol) was slowly added dropwise at 40° C. After the dropwise addition, the reaction was continued for 2 hours, and the 1,2-dichloroethane solvent was evaporated to dryness by distillation under reduced pressure to obtain a reddish-brown oil. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide 80 g. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide was dissolved in 100 g of 1,2-dichloroethane and used directly in the next reaction.

未检出，氯虫苯甲酰胺的定量含量为96.7％，上述两步的收率为84.5％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 1000 mL reaction flask, add 2-amino-5-chloro-N,3-dimethylbenzamide (51.8 g, 96%, 0.25 mol) and 120 g 1,2-dichloroethane, and the temperature was raised to backflow. Slowly add the above-mentioned 1,2-dichloroethane solution of 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide dropwise to the reaction flask, and the dropwise addition is completed. Then the reaction was continued for 1 hour. Then, it was cooled to room temperature, filtered, rinsed and dried to obtain 84.4 g of off-white solid chlorantraniliprole, impurity

Not detected, the quantitative content of chlorantraniliprole was 96.7%, and the yield of the above two steps was 84.5% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydrogen -1H-pyrazole-5-carboxylic acid).

Example 4

In a 500 mL reaction flask, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (50 g, 97%, 0.16 mol) , 150 g of acetonitrile. Phosphorus tribromide (129.9 g, 0.48 mol) was slowly added dropwise at 50° C. After the dropwise addition, the reaction was continued for 2 hours, and the acetonitrile solvent was evaporated to dryness by distillation under reduced pressure to obtain a reddish-brown oily 3-bromo-1-( 3-Chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide 52 g. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide was dissolved in 100 g of acetonitrile and used directly in the next reaction.

未检出，氯虫苯甲酰胺的定量含量为93.1％，上述两步的收率为61％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 500 mL reaction flask, 2-amino-5-chloro-N,3-dimethylbenzamide (33.1 g, 96%, 0.16 mol) and 100 g of acetonitrile were added, and the temperature was raised to reflux. The acetonitrile solution of the above-mentioned 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide was slowly added dropwise to the reaction flask, and the reaction was continued for 1 hour after the dropwise addition. Then, it was cooled to room temperature, filtered, rinsed and dried to obtain 50.6 g of off-white solid chlorantraniliprole. impurities

Not detected, the quantitative content of chlorantraniliprole was 93.1%, and the yield of the above two steps was 61% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydrogen -1H-pyrazole-5-carboxylic acid).

Example 5

In a 500 mL reaction flask, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (50 g, 97%, 0.16 mol) , 150 g of 1,2-dichloroethane. Phosphorus pentabromide (137.7 g, 0.32 mol) was slowly added dropwise at 50° C. After the dropwise addition, the reaction was continued for 2 hours, and the 1,2-dichloroethane solvent was evaporated to dryness by distillation under reduced pressure to obtain a reddish-brown oil. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide 55 g. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide was dissolved in 110 g of 1,2-dichloroethane and used directly in the next reaction.

未检出，氯虫苯甲酰胺的定量含量为94.3％，上述两步的收率为66％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 500-mL reaction flask, add 2-amino-5-chloro-N,3-dimethylbenzamide (33.1 g, 96%, 0.16 mol) and 100 g 1,2-dichloroethane, and the temperature was raised to backflow. The acetonitrile solution of the above-mentioned 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide was slowly added dropwise to the reaction flask, and the reaction was continued for 1 hour after the dropwise addition. Then, it was cooled to room temperature, filtered, rinsed and dried to obtain 54.1 g of off-white solid chlorantraniliprole. impurities

Not detected, the quantitative content of chlorantraniliprole was 94.3%, and the yield of the above two steps was 66% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydrogen -1H-pyrazole-5-carboxylic acid).

Example 6

In a 10L reactor, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (942 g, 97%, 3 mol), 4710 grams of 1,2-dichloroethane. Sulfoxide dibromide (1870.8 g, 9 moles) was slowly added dropwise at 40° C. After the dropwise addition, the reaction was continued for 2 hours, and the 1,2-dichloroethane solvent was evaporated to dryness by distillation under reduced pressure to obtain a reddish-brown oil. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide 1106 g. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl bromide was dissolved in 1200 g of 1,2-dichloroethane and used directly in the next reaction.

未检出，氯虫苯甲酰胺的定量含量为96.3％，上述两步的收率为84.0％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 10-liter reaction kettle, add 2-amino-5-chloro-N,3-dimethylbenzamide (620 g, 96%, 3 moles) and 1800 g 1,2-dichloroethane, and heat up to backflow. Slowly add the above-mentioned 1,2-dichloroethane solution of 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide dropwise to the reaction flask, and the dropwise addition is completed. Then the reaction was continued for 1 hour. Then cooled to room temperature, filtered, rinsed, and dried to obtain 1264.3 g of off-white solid chlorantraniliprole, impurity

Not detected, the quantitative content of chlorantraniliprole was 96.3%, and the yield of the above two steps was 84.0% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydrogen -1H-pyrazole-5-carboxylic acid).

Comparative Example 1

In a 10L pilot-scale reactor, add 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid (942 g, 97%, 3 mol ), 2830 g of acetonitrile. Under the reaction pressure of -0.05Mpa and 30°C, thionyl chloride (1428 g, 12 moles) was slowly added dropwise, and the temperature was raised to 50°C for 2 hours after the addition was completed (the system boiled violently during the heating process). The acetonitrile solvent was evaporated to dryness by distillation under reduced pressure to obtain 1000 g of 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl chloride as a reddish brown oil. 3-Bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carbonyl chloride was dissolved in 1200 g of acetonitrile and used directly in the next reaction.

的含量为1.5wt％，氯虫苯甲酰胺的定量含量为96.1％，上述两步的收率为82.5％(以3-溴-1-(3-氯-2-吡啶基)-4，5-二氢-1H-吡唑-5-甲酸计)。In a 10L reactor, add 2-amino-5-chloro-N,3-dimethylbenzamide (600 g, 96%, 2.9 moles) and 1800 g acetonitrile, the reaction pressure is -0.04Mpa, and the temperature is raised to reflux . The acetonitrile solution of the above-mentioned 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl chloride was slowly added dropwise to the reactor, and the reaction was incubated for 1 hour after the addition was completed, and cooled to After filtering, rinsing and drying at room temperature, 1244 g of off-white solid chlorantraniliprole was obtained. impurities

The content of chlorantraniliprole is 1.5wt%, the quantitative content of chlorantraniliprole is 96.1%, and the yield of the above two steps is 82.5% (with 3-bromo-1-(3-chloro-2-pyridyl)-4,5 -dihydro-1H-pyrazole-5-carboxylic acid).

的含量。其中，如对比例1所示，即使采用了传统反应配合减压的制备方法，当反应规模放大时，最终产物中杂质

的含量仍然得不到有效控制。但如各实施例所示，采用本发明所设计的反应，即使大规模生产氯虫苯甲酰胺，最终产物中杂质

的含量仍然符合要求，利于工业生产。并且，相对于对比例1中的方法，本发明所采用的方法更加安全。另外，采用本发明所设计的反应，不会因为反应原料较传统反应方式发生变化，导致氯虫苯甲酰胺的纯度和收率受到影响，且各实施例表明，本发明中氯虫苯甲酰胺的纯度和收率能够与传统制备方法持平、甚至更好。Comparing each embodiment and comparative example, it can be seen that the reaction designed by the present invention can significantly reduce impurities in the final product

content. Among them, as shown in Comparative Example 1, even if the traditional reaction combined with reduced pressure preparation method is adopted, when the reaction scale is enlarged, impurities in the final product

The content is still not effectively controlled. But as shown in each embodiment, adopt the reaction designed by the present invention, even if chlorantraniliprole is produced on a large scale, impurities in the final product

The content still meets the requirements, which is conducive to industrial production. Moreover, compared with the method in Comparative Example 1, the method adopted in the present invention is safer. In addition, adopt the reaction designed by the present invention, the purity and yield of chlorantraniliprole will not be affected because the reaction raw materials are changed compared with the traditional reaction mode, and each embodiment shows that in the present invention, chlorantraniliprole The purity and yield can be equal to or even better than traditional preparation methods.

The present invention has been described in detail above, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it, and cannot limit the scope of protection of the present invention by this, all according to the spirit of the present invention. Effective changes or modifications should be covered within the protection scope of the present invention.

Claims (10)

1. a preparation method of chlorantraniliprole, is characterized in that, under normal pressure, by 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyridine azole-5-carboxylic acid reacts with an acyl bromination reagent to obtain 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide, the 3-bromo-1-(3 -Chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide reacts with 2-amino-5-chloro-N,3-dimethylbenzamide to obtain the chlorantraniliprole. 2. the preparation method of chlorantraniliprole according to claim 1, is characterized in that, described acyl bromide reagent is one or more in sulfoxide dibromide, phosphorus tribromide or phosphorus pentabromide . 3. the preparation method of chlorantraniliprole according to claim 1, is characterized in that, described 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H- The molar ratio of pyrazole-5-carboxylic acid to the acyl bromination reagent is 1:2-5. 4. the preparation method of chlorantraniliprole according to claim 1, is characterized in that, described 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H- The pyrazole-5-carboxylic acid is reacted with the acyl bromide reagent in the presence of a solvent, and the temperature of the reaction is controlled to be a temperature between 0°C and the boiling point of the solvent; and/or, the time of the reaction is controlled 1 to 10 hours. 5. the preparation method of chlorantraniliprole according to claim 4, is characterized in that, the temperature that controls described reaction is the temperature between 30 ℃ to the boiling point of described solvent; And/or, controls described reaction The time is 2 to 5 hours. 6. the preparation method of chlorantraniliprole according to claim 4, is characterized in that, described solvent is one or more in acetonitrile, toluene, chlorobenzene, ethylene dichloride, xylene; and/ Or, the mass ratio of the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid to the solvent is 1:1～10 . 7. the preparation method of chlorantraniliprole according to claim 1, is characterized in that, described 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromine is reacted with the 2-amino-5-chloro-N,3-dimethylbenzamide in the presence of a solvent, and the temperature of the reaction is controlled to be a temperature between 0°C and the boiling point of the solvent; and /or, the reaction time is controlled to be 0.5 to 10 hours. 8. the preparation method of chlorantraniliprole according to claim 7, is characterized in that, the temperature that controls described reaction is the temperature between 50 ℃ to the boiling point of described solvent; And/or, controls described reaction The time is 1 to 2 hours. 9. the preparation method of chlorantraniliprole according to claim 7, is characterized in that, described solvent is one or more in acetonitrile, toluene, chlorobenzene, ethylene dichloride, xylene, cyclohexane and/or, the mass ratio of the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide to the solvent is 1:1-5. 10. the preparation method of chlorantraniliprole according to any one of claims 1 to 9, is characterized in that, described preparation method is specifically as follows: The 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid and the solvent were added to the reactor, and the The acyl bromide reagent, after the dropwise addition was completed, the incubation reaction was continued, and after the reaction was completed, the solvent was evaporated to dryness under reduced pressure to obtain the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5- formyl bromide; dissolve the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide in a solvent to obtain 3-bromo-1-(3-chloro- 2-pyridyl)-1H-pyrazole-5-formyl bromide solution; The 2-amino-5-chloro-N,3-dimethylbenzamide and the solvent were added to the reactor, and the 3-bromo-1-(3-chloro-2-pyridine was added dropwise at the reaction temperature base)-1H-pyrazole-5-formyl bromide solution, continue the insulation reaction after the dropwise addition, and after the reaction finishes, obtain the chlorantraniliprole through cooling, filtration, rinsing and drying; Wherein, the molar ratio of controlling the 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid to the acyl bromination reagent is 1 : 2 to 10, control the 3-bromo-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-formyl bromide and the 2-amino-5-chloro-N,3- The molar ratio of dimethylbenzamide is 1:0.8～1.2.