Synthetic method of diethyl methyl-phosphonite and glufosinate-ammonium

Abstract

The invention discloses a synthetic method of diethyl methyl-phosphonite and glufosinate-ammonium. The synthetic method comprises the following steps: carrying out a reaction between diethyl phosphite and chloromethane gas in the presence of an acid binding agent to prepare diethyl methylphosphonite, and filtering after reaction, wherein the generated diethyl methylphosphonite exists in a filtrate; dropwisely adding an organic solvent, in which a reducing agent is dissolved, into the filtrate so as to reduce diethyl methylphosphonite into diethyl methyl-phosphonite, distilling a reaction solution after the reaction so as to obtain diethyl methyl-phosphonite, and preparing glufosinate-ammonium by using diethyl methyl-phosphonite as an intermediate. According to the invention, diethyl phosphite is used as a raw material; reaction raw materials are cheap and easily available; the reaction process is simple and easy to operate and is green and environmentally friendly; atom utilization rate is high; quality of the obtained product is good; yield is high; a new idea is provided for the synthesis of glufosinate-ammonium; preparation cost of glufosinate-ammonium is also reduced; and the synthetic method has wide application value.

Description

technical field

[0001] The invention relates to a synthesis method of diethyl methylphosphonite and glufosinate-ammonium, in particular to a green and environment-friendly synthesis method of diethyl methylphosphonite and glufosinate-ammonium, and belongs to the technical field of herbicides. technical background

[0002] Glufosinate-ammonium (glufosinate-ammonium) was developed and produced by Hearst (now owned by Bayer after several mergers), chemical name 4-[hydroxy (methyl) phosphono]-DL-homoalanine, other name glufosinate-ammonium Ammonium phosphonate, Basta, Buster, etc., are phosphonic acid herbicides, glutamine synthesis inhibitors, non-selective (killing) contact herbicides. It was developed in the 1980s and registered as a herbicide in 1984. Glufosinate-ammonium is a large-tonnage pesticide variety in the world, and it is also the second largest genetically modified crop resistant to herbicides in the world. Low toxicity, relatively safe, easy to degrade in soil,...

Examples

Embodiment 1

[0035] In a 1L autoclave, add 138g of diethyl phosphite and 101g of anhydrous triethylamine, close the autoclave, and use N 2 The air in the kettle was replaced, the temperature was raised to 110°C with stirring, and methyl chloride gas was slowly introduced to maintain the pressure in the kettle at 0.4-0.8 MPa during the reaction. After 4 hours of reaction, the temperature was lowered and the pressure was released, triethylamine hydrochloride was removed by suction filtration, the filtrate was transferred to a 1000 mL four-necked flask, the temperature was cooled to 0 °C with an ice-salt bath, and 200 mL of a THF solution dissolved in 19 g of lithium tetrahydrogen was slowly added dropwise. After the dropwise addition, continue to insulate and stir for 120 min. The temperature was slowly raised for distillation, and 126.1 g of fractions with a boiling point of 120-122°C were collected. The content of diethyl methylphosphonite was detected to be 98.5%, and the yield was 91.3%....

Embodiment 2

[0037] In a 1L autoclave, add 138g of diethyl phosphite and 222g of tri-n-butylamine, close the autoclave, and use N 2 Replace the air in the kettle, stir and raise the temperature to 100°C, and slowly feed in methyl chloride gas to maintain the pressure in the kettle at 0.4-0.8MPa. After reacting for 3 hours, the temperature was lowered and the pressure was released, tributylamine hydrochloride was removed by suction filtration, the filtrate was transferred to a 1000 mL four-neck flask, the temperature was cooled to 5 °C with an ice-salt bath, and 200 mL of a methyl tetrahydrofuran solution dissolved in 19 g of lithium tetrahydrogen was slowly added dropwise. After the dropwise addition, continue to insulate and stir for 90 min. The temperature was slowly raised for distillation, and 120.8 g of fractions with a boiling point of 120-122°C were collected. The content of diethyl methylphosphonite was detected to be 98.8%, and the yield was 87.8%.

Embodiment 3

[0039] In a 1L autoclave, add 138g of diethyl phosphite and 367.5g of triphenylamine, close the autoclave, and use N 2 Replace the air in the kettle, stir and raise the temperature to 120°C, slowly feed in methyl chloride gas to maintain the pressure in the kettle at 0.4-0.8MPa. After reacting for 2 hours, the temperature was lowered and the pressure was released, triphenylamine hydrochloride was removed by suction filtration, the filtrate was transferred to a 1000 mL four-neck flask, the temperature was lowered to 10°C with a cold water bath, and 200 mL of ether solution dissolved in 24 g of sodium hydride was slowly added dropwise. After the dropwise addition, continue to insulate and stir for 60 min. The temperature was slowly raised to distill, and 119.5 g of fractions with a boiling point of 120-122°C were collected. The content of diethyl methylphosphonite was detected to be 98.9%, and the yield was 86.9%.

technical field

[0001] The invention relates to a synthesis method of diethyl methylphosphonite and glufosinate-ammonium, in particular to a green and environment-friendly synthesis method of diethyl methylphosphonite and glufosinate-ammonium, and belongs to the technical field of herbicides. technical background

[0002] Glufosinate-ammonium (glufosinate-ammonium) was developed and produced by Hearst (now owned by Bayer after several mergers), chemical name 4-[hydroxy (methyl) phosphono]-DL-homoalanine, other name glufosinate-ammonium Ammonium phosphonate, Basta, Buster, etc., are phosphonic acid herbicides, glutamine synthesis inhibitors, non-selective (killing) contact herbicides. It was developed in the 1980s and registered as a herbicide in 1984. Glufosinate-ammonium is a large-tonnage pesticide variety in the world, and it is also the second largest genetically modified crop resistant to herbicides in the world. Low toxicity, relatively safe, easy to degrade in soil,...

Examples

Embodiment 1

[0035] In a 1L autoclave, add 138g of diethyl phosphite and 101g of anhydrous triethylamine, close the autoclave, and use N 2 The air in the kettle was replaced, the temperature was raised to 110°C with stirring, and methyl chloride gas was slowly introduced to maintain the pressure in the kettle at 0.4-0.8 MPa during the reaction. After 4 hours of reaction, the temperature was lowered and the pressure was released, triethylamine hydrochloride was removed by suction filtration, the filtrate was transferred to a 1000 mL four-necked flask, the temperature was cooled to 0 °C with an ice-salt bath, and 200 mL of a THF solution dissolved in 19 g of lithium tetrahydrogen was slowly added dropwise. After the dropwise addition, continue to insulate and stir for 120 min. The temperature was slowly raised for distillation, and 126.1 g of fractions with a boiling point of 120-122°C were collected. The content of diethyl methylphosphonite was detected to be 98.5%, and the yield was 91.3%....

Embodiment 2

[0037] In a 1L autoclave, add 138g of diethyl phosphite and 222g of tri-n-butylamine, close the autoclave, and use N 2 Replace the air in the kettle, stir and raise the temperature to 100°C, and slowly feed in methyl chloride gas to maintain the pressure in the kettle at 0.4-0.8MPa. After reacting for 3 hours, the temperature was lowered and the pressure was released, tributylamine hydrochloride was removed by suction filtration, the filtrate was transferred to a 1000 mL four-neck flask, the temperature was cooled to 5 °C with an ice-salt bath, and 200 mL of a methyl tetrahydrofuran solution dissolved in 19 g of lithium tetrahydrogen was slowly added dropwise. After the dropwise addition, continue to insulate and stir for 90 min. The temperature was slowly raised for distillation, and 120.8 g of fractions with a boiling point of 120-122°C were collected. The content of diethyl methylphosphonite was detected to be 98.8%, and the yield was 87.8%.

Embodiment 3

[0039] In a 1L autoclave, add 138g of diethyl phosphite and 367.5g of triphenylamine, close the autoclave, and use N 2 Replace the air in the kettle, stir and raise the temperature to 120°C, slowly feed in methyl chloride gas to maintain the pressure in the kettle at 0.4-0.8MPa. After reacting for 2 hours, the temperature was lowered and the pressure was released, triphenylamine hydrochloride was removed by suction filtration, the filtrate was transferred to a 1000 mL four-neck flask, the temperature was lowered to 10°C with a cold water bath, and 200 mL of ether solution dissolved in 24 g of sodium hydride was slowly added dropwise. After the dropwise addition, continue to insulate and stir for 60 min. The temperature was slowly raised to distill, and 119.5 g of fractions with a boiling point of 120-122°C were collected. The content of diethyl methylphosphonite was detected to be 98.9%, and the yield was 86.9%.

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