Unlock instant, AI-driven research and patent intelligence for your innovation.

Synthetic method of 4-(6-chloroquinoxalin-2-yloxy) phenol

A synthesis method and a technology for chloroquinoxaline, applied in directions such as organic chemistry, can solve problems such as the unfavorable large-scale industrial production of quizalofop-p-ethyl and oxaflutole herbicides, the difficulty of fully recovering the solvent, and the long reaction time, thereby saving investment and The effect of production cost, stable production and application, simple and easy operation

Active Publication Date: 2011-11-09
JINGBO AGROCHEM TECH CO LTD
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Among the above-mentioned several options, (1), (2), and (3) exist solvents that are difficult to recover completely, and require further purification before applying mechanically, resulting in the disadvantages of high cost and complicated process; (4) are more suitable for industrial production, but due to the Under the condition of strong alkaline aqueous solution, the raw material 2,6-dichloroquinoxaline is easily hydrolyzed, resulting in the defects of low yield, long reaction time and large amount of waste water
[0005] Due to the existence of the above-mentioned shortcomings, it is unfavorable for the large-scale industrial production of quizalofop and fenoxaclo-methyl herbicides

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
  • Synthetic method of 4-(6-chloroquinoxalin-2-yloxy) phenol
  • Synthetic method of 4-(6-chloroquinoxalin-2-yloxy) phenol

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Preparation of hydroquinone alkaline aqueous solution:

[0030] Weigh 325kg of hydroquinone and 400kg of water into a 1000L reactor, keep the dissolution temperature at 40°C, replace the system with nitrogen and seal it, add 320kg of 30% sodium hydroxide solution dropwise, after the dropwise addition, keep it warm for one hour to At room temperature, put it in the kettle for later use.

[0031] Etherification reaction:

[0032] Weigh 460kg of 2,6-dichloroquinoxaline and 1200kg of toluene into a 3000L reaction kettle, then add 2kg of benzyltriethylammonium chloride, replace the system with nitrogen and seal it, stir and decompose at 80°C, and start Add the prepared hydroquinone alkaline aqueous solution dropwise for about 1 hour. After the dropwise addition, keep it warm for another 4 hours. Use liquid chromatography to track the disappearance of the 2,6-dichloroquinoxaline raw material, and acidify it to pH with concentrated hydrochloric acid. = 6-7, cooled to 50°C fo...

Embodiment 2

[0036] The preparation of hydroquinone alkaline aqueous solution: (with embodiment one)

[0037] Etherification reaction:

[0038] Weigh 460kg of 2,6-dichloroquinoxaline and put it into a 3000L reactor and add the toluene recovery solution of Example 1 and add 10kg of fresh toluene. Other steps are the same as in Example 1. Obtain 4-(6-chloroquinoxalin-2-yl oxygen) phenol 610kg, liquid chromatography analysis content 96.2% yield 95.3%

[0039] Toluene recovery:

[0040] The etherified suction filtrate was added to a separatory bottle at room temperature, and the layers were static, and the lower water layer was separated. The crude toluene weighed 1191 kg, and the hydroquinone content was determined to be 4.0% by liquid chromatography.

[0041] It can be seen from this embodiment that the organic solvent used can be recycled and used mechanically, so that the unreacted hydroquinone in the solvent enters the reaction process again and is utilized to the greatest extent, and t...

Embodiment 3

[0043] Preparation of hydroquinone alkaline aqueous solution:

[0044] Weigh 340kg of hydroquinone, 166kg of potassium carbonate and 300kg of water into a 1000L reactor, keep the dissolution temperature at 40°C, replace the system with nitrogen and seal it, keep it warm for two hours and drop to room temperature, then put it in the kettle for later use.

[0045] Etherification reaction:

[0046]Weigh 460kg of 2,6-dichloroquinoxaline and 1600kg of toluene into a 3000L reaction kettle, then add 2kg of tetrabutylammonium bromide, replace the system with nitrogen and seal it, stir and raise the temperature to reflux, react for 4 hours, use liquid phase Chromatography traces the disappearance of 2,6-dichloroquinoxaline raw material, acidify with concentrated hydrochloric acid to pH=6-7, cool down to 50°C for suction filtration, rinse with 200kg of hot water at 50°C, dry the filter cake in an oven at 80°C, weigh Weight 610kg, liquid chromatography analysis content 97%, calculated y...

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 belongs to the organic synthesis technical field, and provides a new synthetic method of 4-(6-chloroquinoxalin-2-yloxy) phenol. In the method, alkaline aqueous solution of hydroquinone is adopted to react with 2,6-dichloroquinoxaline, and an organic solvent with a phase transfer catalyst is taken as a reaction medium to reduce side hydrolyzation reaction caused by direct contact between raw materials and alkali liquor, thus improving the stability of the whole synthetic reaction; compared with the traditional process, the synthetic method has the advantages of simple and feasible operation, higher yield and higher content, and use and recovery of the solvent greatly reduce generation of waste water, alleviate environmental pollution and lower production cost; and the corresponding excessive hydroquinone used in reaction is used with the solvent and is recovered to the most extent, thus a special hydroquinone recovery unit is not required and investment and production cost is saved; and the process is very stable in production application.

Description

technical field [0001] The invention belongs to the technical field of organic synthesis, and relates to a method for synthesizing the intermediate 4-(6-chloroquinoxalin-2-yloxy)phenol of the pesticide quizalofop and the herbicide fenoxadenyl. Background technique [0002] Quizalofop is a systemic high-efficiency selective post-emergence herbicide, which can effectively control 1-year and perennial grass weeds; agent, is a fatty acid synthesis inhibitor. It also has a good control effect on many major annual and perennial grass weeds, and 4-(6-chloroquinoxalin-2-yloxy)phenol is a key intermediate for the synthesis of quizalofop and oxaclofop-methyl. Quality and yield directly determine product quality and cost. [0003] At present, the domestic method for synthesizing 4-(6-chloroquinoxaline-2-yloxy)phenol is mainly prepared by condensation reaction of 2,6-dichloroquinoxaline and hydroquinone under inorganic alkali conditions, wherein the solvent And the selection of inorg...

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
Patent Type & Authority Patents(China)
IPC IPC(8): C07D241/44
Inventor 史庆苓郑亭路刘英贤张建林胡清亮
Owner JINGBO AGROCHEM TECH CO LTD