Synthesis method of 2-(2,6-diethyl-4-methylphenyl)propanedinitrile

A synthesis method and technology of diethylbromobenzene are applied in chemical instruments and methods, preparation of carboxylic acid nitrile, preparation of organic compounds, etc., can solve the problems of difficulty in recovery and application, high cost, etc., and achieve the avoidance of high cost, cost reduction effect

Active Publication Date: 2019-02-12
JIANGSU FUDING CHEM
View PDF3 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Wanqin provided a method for synthesizing 2-(2,6-diethyl-4-methylbenzene)malononitrile in "Studies on the Synthesis of the Herbicide Pinoxaden", which uses 2,6- Diethyl-4-methylbromobenzene and malononitrile are raw materials, triphenylphosphorous palladium chloride is a catalyst, and xylene is a reaction solvent, and the reaction obtains 2-(2,6 -Diethyl-4-methylbenzene) malononitrile, although the yield can reach 92.6%, the amount of triphenylphosphorous palladium chloride is 16wt% of 2,6-diethyl-4-methylbromobenzene , the price of palladium salt catalyst is as high as 3.5-5 million / ton, and it is difficult to recycle and apply mechanically, resulting in high cost

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Synthesis method of 2-(2,6-diethyl-4-methylphenyl)propanedinitrile

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] Put 120g (3mol) sodium hydroxide, 600g N-methylpyrrolidone, and 79g (1.2mol) malononitrile into the four-necked bottle. After feeding, replace the gas with nitrogen for 3 times, keep the nitrogen atmosphere, and keep the reaction at 25-35°C 1h. 227 g (1 mol) of 4-methyl-2,6-diethylbromobenzene and 6.8 g of bis(triphenylphosphine)nickel dibromide were charged. After the feeding is completed, the temperature is raised to 110-120°C within about 1 hour, and the reaction is held for another 12 hours. At this time, the content of 4-methyl-2,6-diethylbromobenzene is <0.5%, and the reaction is terminated.

[0025] The reaction solution was cooled to 25-35°C, 200 g of water was added, the pH was adjusted to 2 with concentrated hydrochloric acid, extracted with ethyl acetate, and the organic phase was concentrated to obtain a crude product. Add 100g of methanol, dissolve the crude product at 60°C, lower the temperature to 0-5°C, precipitate a solid, stir for 1 hour, filter, and ...

Embodiment 2

[0027] Put 120g of sodium hydroxide, 600g of N-methylpyrrolidone, and 79g of malononitrile into the four-necked bottle. After the feeding, replace the gas with nitrogen for 3 times, keep the nitrogen atmosphere, and keep the reaction at 25-35°C for 1h. 227 g of 4-methyl-2,6-diethylbromobenzene and 6.8 g of bistriphenylphosphine palladium dichloride were added. After the feeding is completed, slowly raise the temperature to 110-120°C, and then keep the temperature for 12 hours. At this time, the content of 4-methyl-2,6-diethylbromobenzene is <0.5%, and the reaction is terminated.

[0028] The reaction solution was cooled to 25-35°C, 200g of water was added, the pH was adjusted to 2 with concentrated hydrochloric acid, the product was extracted with ethyl acetate, and concentrated to obtain a crude product. Add 100g of methanol, dissolve the solid at 60°C, lower the temperature to 0-5°C, precipitate the solid, stir for 1 hour, filter, and dry to obtain 188.9g of gray product (co...

Embodiment 3

[0030] Put 168g (3mol) of potassium hydroxide, 600g of N-methylpyrrolidone, and 79g (1.2mol) of malononitrile into the four-necked bottle. After feeding, replace the gas with nitrogen for 3 times, keep the nitrogen atmosphere, and keep the reaction at 25-35°C 1h. 227 g (1 mol) of 4-methyl-2,6-diethylbromobenzene and 6.8 g of bis(triphenylphosphine)nickel dibromide were charged. After the feeding is completed, the temperature is raised to 110-120°C within about 1 hour, and the reaction is held for another 12 hours. At this time, the content of 4-methyl-2,6-diethylbromobenzene is <0.5%, and the reaction is terminated.

[0031] The reaction solution was cooled to 25-35°C, 200 g of water was added, the pH was adjusted to 2 with concentrated hydrochloric acid, extracted with ethyl acetate, and the organic phase was concentrated to obtain a crude product. Add 100g of methanol, dissolve the crude product at 60°C, lower the temperature to 0-5°C, precipitate a solid, stir for 1 hour, ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a synthesis method of 2-(2,6-diethyl-4-methylphenyl)propanedinitrile. The method comprises the following steps of using 4-methyl-2,6-diethyl bromobenzene and propanedinitrile as raw materials, and in an alkaline condition, catalyzing a reaction by a catalyst bis(triphenylphosphine)nickel(ii) bromide to obtain the 2-(2,6-diethyl-4-methylphenyl)propanedinitrile. According tothe synthesis method, a high-price palladium salt catalyst is replaced with the bis(triphenylphosphine)nickel(ii) bromide; the difficult problems that a palladium salt is higher in cost and is difficult to recycle and reuse are avoided; and not only is the cost decreased by a wide margin, but also, on the premise of decreasing the consumption of the catalyst, the yield can reach 90%, which is approximate to that by adopting the palladium salt catalyst, and is even superior to that of the palladium salt catalyst.

Description

technical field [0001] The invention belongs to the field of pesticide synthesis, and in particular relates to a synthesis method of 2-(2,6-diethyl-4-methylbenzene)malononitrile. Background technique [0002] Pinoxaden was developed by Syngenta and launched in 2006. It belongs to the new phenylpyrazoline herbicides and is an inhibitor of acetyl-CoA carboxylase (ACC), causing fatty acid synthesis to be blocked and cell growth Division stops, the lipid-containing structure of the cell membrane is destroyed, and the weed dies. Pinoxaden has systemic conductivity and is mainly used in grains to control gramineous weeds after emergence. The dosage of active ingredients is 30-60g / hm 2 . [0003] The structural formula of pinoxaden is as follows: Chemical name: 8-(2,6-diethyl-4-methylphenyl)-1,2,4,5-tetrahydro-7-oxo-7H-pyrazol[1,2-d][1 ,4,5] Oxadiazepine-9-yl-2,2-dimethylpropionate; CAS No.: 243973-20-8. [0004] 2-(2,6-diethyl-4-methylbenzene)malononitrile is an intermediate...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): C07C253/30C07C255/33
CPCC07C253/30C07C255/33
Inventor常青张胜山
OwnerJIANGSU FUDING CHEM