CN103896906A - New synthetic method of pesticide fludioxonil intermediate - Google Patents

Abstract

The invention discloses a new synthetic method of a pesticide fludioxonil intermediate. The method comprises the steps of firstly preparing bromoacetonitrile triphenyl phosphate white solid; then preparing 4-formyl-2,2-difluoro-1,3-benzodioxole; finally dissolving 4-formyl-2,2-difluoro-1,3-benzodioxole and bromoacetonitrile triphenyl phosphate into dichloromethane at room temperature, dropping a small amount of a 10% sodium hydroxide solution, and reacting to obtain (E)-3-(2,2-difluoro-1,3-benzodioxolame-4-yl) acrylonitrile. By adopting the method disclosed by the invention, the technical problems that an original synthetic method is more in steps, long in period, relatively highly-toxic in raw materials, serious in three-waste pollution and high in cost are solved.

Description

A kind of novel synthesis of agricultural chemicals fludioxonil intermediate

Technical field

The present invention relates to a kind of chemical synthesis process, be specifically related to a kind of novel synthesis of agricultural chemicals fludioxonil intermediate.

Background technology

The commodity of fludioxonil are by name suitable when happy, are a kind of novel, efficient, safe sterilant, are one of seed treatment agents of current global sales maximum.Because its consumption is few, the lasting period is long, is chosen as by EPA the product that is free from risk, and has extremely wide market outlook.Fludioxonil is a kind of wide-spectrum bactericide of interior absorption, can be used as blade face bactericidal agent for preventing and treating and avenges rotten sickle and embrace bacterium, wheat net raw meat black rot etc., especially gray mold is had to special efficacy.Coughing up mattress nitrile uses mainly as the seed treatment agent of cereals and non-cereals crop.

At present the route of synthetic (E)-3-(2,2-bis-fluoro-1,3-benzo dioxolane-4-yl) vinyl cyanide is as follows:

A.2,2-bis-is fluoro-1, and 3-benzo two is disliked under luxuriant low temperature and n-Butyl Lithium reaction obtains compound a;

B. compound a obtains compound b through aminating reaction;

C. compound b forms diazenium compound c under the condition of Sodium Nitrite and hydrochloric acid;

D. compound c obtains compound d with acrylonitrile reactor under the existence of cuprous chloride;

E. the hydrogenchloride that compound d removes a part obtains fludioxonil intermediate (E)-3-(2,2-bis-fluoro-1,3-benzo dioxolane-4-yl) vinyl cyanide;

This process flow steps is many, and the cycle is long, uses the raw material that toxicity is larger, and three-waste pollution is serious, and cost is high, and comprehensive benefit is poor.Therefore develop the technique that low-cost and easy-to operational danger is little extremely important.

Summary of the invention

For overcoming deficiency of the prior art, the invention provides a kind of novel synthesis of agricultural chemicals fludioxonil intermediate.

For realizing above-mentioned technical purpose, reach above-mentioned technique effect, the present invention is achieved through the following technical solutions:

The novel synthesis of agricultural chemicals fludioxonil intermediate, comprises the following steps:

Step 1) in the toluene solution of bromoacetonitrile, add triphenyl phosphorus, back flow reaction, after 4 hours, is filtered and is obtained bromoacetonitrile triphenyl microcosmic salt white solid;

Step 2) under low temperature, at 2,2-bis-fluoro-1,3-benzo two is disliked the cyclohexane solution that slowly drips n-Butyl Lithium in luxuriant tetrahydrofuran solution, reacts after 1 hour, more slowly drips N, dinethylformamide, then reacts 30 minutes, is more slowly warming up to room temperature, after 30 minutes, with the hydrochloric acid soln cancellation reaction of 2mol/L, ethyl acetate extraction, organic layer is washed with saturated common salt, and anhydrous sodium sulfate drying obtains 4-aldehyde radical-2 after evaporating solvent, 2-bis-is fluoro-1, and 3-benzo two is disliked luxuriant;

Step 3) lower 4-aldehyde radical-2 of room temperature, 2-bis-fluoro-1,3-benzo two is disliked luxuriant and bromoacetonitrile triphenyl microcosmic salt and is dissolved in methylene dichloride, then splash into a small amount of 10% sodium hydroxide solution, after reaction, obtain (E)-3-(2,2-bis-is fluoro-1,3-benzo dioxolane-4-yl) vinyl cyanide;

Described step (1), (2), (3) synthetic reaction formula are:

Beneficial effect of the present invention:

The present invention is with bromoacetonitrile and 2,2-bis-fluoro-1,3-benzo two is disliked luxuriant for starting raw material, and the product purity of step (1) and step (2) is enough high, does not need to process intermediate, step is simple, it is convenient to process, and the reaction of step (3) is common Wittig reaction, simple to operate, productive rate is higher, has reduced cost; Reduce middle this toxicity of vinyl cyanide and the larger raw material of damage ratio used, shortened the production cycle.

Above-mentioned explanation is only the general introduction of technical solution of the present invention, in order to better understand technique means of the present invention, and can be implemented according to the content of specification sheets, below is described in detail as follows with preferred embodiment of the present invention.The specific embodiment of the present invention is provided in detail by following examples.

Embodiment

Below in conjunction with embodiment, describe the present invention in detail.

The novel synthesis of agricultural chemicals fludioxonil intermediate, comprises the following steps:

Step 1) in the toluene solution of bromoacetonitrile, add triphenyl phosphorus, back flow reaction, after 4 hours, is filtered and is obtained bromoacetonitrile triphenyl microcosmic salt white solid;

Step 2) under low temperature, at 2,2-bis-fluoro-1,3-benzo two is disliked the cyclohexane solution that slowly drips n-Butyl Lithium in luxuriant tetrahydrofuran solution, reacts after 1 hour, more slowly drips N, dinethylformamide, then reacts 30 minutes, is more slowly warming up to room temperature, after 30 minutes, with the hydrochloric acid soln cancellation reaction of 2mol/L, ethyl acetate extraction, organic layer is washed with saturated common salt, and anhydrous sodium sulfate drying obtains 4-aldehyde radical-2 after evaporating solvent, 2-bis-is fluoro-1, and 3-benzo two is disliked luxuriant;

Step 3) lower 4-aldehyde radical-2 of room temperature, 2-bis-fluoro-1,3-benzo two is disliked luxuriant and bromoacetonitrile triphenyl microcosmic salt and is dissolved in methylene dichloride, then splash into a small amount of 10% sodium hydroxide solution, after reaction, obtain (E)-3-(2,2-bis-is fluoro-1,3-benzo dioxolane-4-yl) vinyl cyanide;

Described step (1), (2), (3) synthetic reaction formula are:

Embodiment 1:

Step 1) 10 grams of bromoacetonitriles are joined in the toluene of 300 milliliters, then add 21.8 grams of triphenyl phosphorus, back flow reaction, after 4 hours, is filtered white precipitate and is obtained 30.5 grams of bromoacetonitrile triphenyl microcosmic salts;

Step 2) 15.8 gram 2, 2-bis-fluoro-1, 3-benzo two is disliked in the tetrahydrofuran (THF) that the luxuriant 200ml of joining is dry, under nitrogen protection, be cooled to-75 ℃, then slowly splash into the cyclohexane solution that contains 6.4 grams of n-Butyl Lithiums, react after 1 hour, slowly drip again 7.31 grams of N, dinethylformamide, drip off rear reaction 30 minutes, slowly be warming up to again room temperature, after 30 minutes, with the hydrochloric acid soln cancellation reaction of 2mol/L, ethyl acetate extraction, the washing of organic layer saturated common salt, anhydrous sodium sulfate drying, boil off solvent and obtain 16.5 grams of 4-aldehyde radical-2, 2-bis-fluoro-1, 3-benzo two is disliked luxuriant,

Step 3) under room temperature 10 grams of 4-aldehyde radical-2,2-bis-fluoro-1,3-benzo two is disliked luxuriant and 20.5 grams of bromoacetonitrile triphenyl microcosmic salts and is dissolved in 500ml methylene dichloride, then splashes into the sodium hydroxide solution of 2 milliliter 10%, and room temperature reaction spends the night, then use 200 milliliters of washings, organic phase anhydrous sodium sulfate drying, precipitation obtains (E)-3-(2,2-bis-fluoro-1 of 6.5 grams after purifying, 3-benzo dioxolane-4-yl) vinyl cyanide product, purity 98.12%.

The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (1)

1. the novel synthesis of agricultural chemicals fludioxonil intermediate, is characterized in that, comprises the following steps:

Step 1) in the toluene solution of bromoacetonitrile, add triphenyl phosphorus, back flow reaction, after 4 hours, is filtered and is obtained bromoacetonitrile triphenyl microcosmic salt white solid;

Step 2) under low temperature, at 2,2-bis-fluoro-1,3-benzo two is disliked the cyclohexane solution that slowly drips n-Butyl Lithium in luxuriant tetrahydrofuran solution, reacts after 1 hour, more slowly drips N, dinethylformamide, then reacts 30 minutes, is more slowly warming up to room temperature, after 30 minutes, with the hydrochloric acid soln cancellation reaction of 2mol/L, ethyl acetate extraction, organic layer is washed with saturated common salt, and anhydrous sodium sulfate drying obtains 4-aldehyde radical-2 after evaporating solvent, 2-bis-is fluoro-1, and 3-benzo two is disliked luxuriant;

Step 3) lower 4-aldehyde radical-2 of room temperature, 2-bis-fluoro-1,3-benzo two is disliked luxuriant and bromoacetonitrile triphenyl microcosmic salt and is dissolved in methylene dichloride, then splash into a small amount of 10% sodium hydroxide solution, after reaction, obtain (E)-3-(2,2-bis-is fluoro-1,3-benzo dioxolane-4-yl) vinyl cyanide;

Described step (1), (2), (3) synthetic reaction formula are: