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

Method for preparing 2-[1H-pyrazole-5-radical]-4H-3, 1-benzoxazine-4-ketone compound

A technology of -4H-3 and ketone compounds, applied in the direction of organic chemistry, can solve the problems of dangerous oxidation operation, long steps, large amount of waste water, etc.

Inactive Publication Date: 2011-04-27
中国中化股份有限公司 +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The reaction has disadvantages such as dangerous oxidation operation, long steps, and large amount of waste water.

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
  • Method for preparing 2-[1H-pyrazole-5-radical]-4H-3, 1-benzoxazine-4-ketone compound
  • Method for preparing 2-[1H-pyrazole-5-radical]-4H-3, 1-benzoxazine-4-ketone compound
  • Method for preparing 2-[1H-pyrazole-5-radical]-4H-3, 1-benzoxazine-4-ketone compound

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046] Example 1: Synthesis of 3-chloro-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid

[0047]

[0048] Add 3-chloro-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid ethyl ester (15.90 g, 50.00 mmol ), THF (100 milliliters), water (100 milliliters), sodium hydroxide (3.03 grams, 75.00 millimoles), react at room temperature for 6 hours, remove THF under reduced pressure, add water (50 milliliters) and ethyl acetate (20 milliliters) Extraction, the inorganic phase was acidified to pH = 2 with hydrochloric acid, and then extracted with dichloromethane (75 ml × 3 times), the organic phase was washed with anhydrous MgSO 4 Drying, desolvation under reduced pressure gave 12.68 grams of white crystalline powder, HPLC normalized content was 98% (analysis conditions: chromatographic column is ZORBAX Eclipse XDB-C8 4.6 * 150mm 5 μm, mobile phase is acetonitrile: water=70: 30), m.p. 57-59°C, yield 95%.

[0049] 1 H NMR (300MHz, CDCl 3 ( dd, 1H). ...

Embodiment 2

[0050] Example 2: Synthesis of 3-bromo-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid

[0051]

[0052] Add 3-chloro-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid ethyl ester (18.50 g, 50.78 mmol ), THF (100 milliliters), water (100 milliliters), sodium hydroxide (3.06 grams, 76.17 millimoles), react at room temperature for 6 hours, remove THF under reduced pressure, add water (50 milliliters) and ethyl acetate (20 milliliters) Extraction, the inorganic phase was acidified to pH = 2 with hydrochloric acid, and then extracted with dichloromethane (75 ml × 3 times), the organic phase was washed with anhydrous MgSO 4 Drying, desolvation under reduced pressure gave 15.25 grams of white crystalline powder, HPLC normalized content was 98% (analysis conditions: chromatographic column is ZORBAX Eclipse XDB-C8 4.6 * 150mm 5 μm, mobile phase is acetonitrile: water=70: 30), m.p.66-68°C, yield 96%.

[0053] 1 H NMR (300MHz, CDCl 3 ( dd, 1H).

...

Embodiment 3

[0055] Example 3: 6-chloro-2-[3-chloro-1-(3-chloro-2-pyridyl)-1H-pyrazol-5-yl]-8-methyl-4H-3,1-benzene Synthesis of oxazin-4-one

[0056]

[0057] Methanesulfonyl chloride (6.02 g, 52.57 mmol) was added to a 250 ml reaction flask, and 3-chloro-1-(3-chloro-2-pyridyl)-4,5-dihydro-1H-pyrazole was added dropwise -A solution of 5-formic acid (12.68 g, 47.77 mmol), acetonitrile (50 ml) and triethylamine (5.31 g, 52.57 mmol) was reacted at room temperature for 1 hour, and 2-amino-5-chloro-3- Toluic acid (8.87 g, 47.77 mmol), reacted for 30 minutes, added dropwise triethylamine (10.62 g, 105.14 mmol), reacted for 1 hour, added dropwise methanesulfonyl chloride (6.02 g, 52.57 mmol), reacted 6 hours. Stand still, filter, the filter cake is a yellow solid, wash the filter cake with THF (20 ml × 2 times), the filtrate is precipitated under reduced pressure, and column chromatography (ethyl acetate / petroleum ether=1 / 5) gives 7.38 g of a yellow solid , the HPLC normalized content was ...

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 provides a method for preparing a 2-[1H- pyrazole-5-base]-4H-3, 1-benzoxazine-4-ketone compound (I). 3-halo-1-(3-chlorine-2-pyridyl)-4 and 5-dihydro-1H-pyrazole-5-formic ether (III) are used as raw materials, and a target product is prepared by hydrolyzing, coupling and simultaneously carrying out an oxidation reaction. A reaction formula is shown as follows, and radicals in the formula are presented in the specification. The invention also provides a compound of a general formula (II) and a preparation method thereof.

Description

technical field [0001] The invention belongs to the field of organic synthesis, and in particular relates to a method for preparing 2-[1H-pyrazol-5-yl]-4H-3,1-benzoxazin-4-one compounds. Background technique [0002] 2-[1H-pyrazol-5-yl]-4H-3,1-benzoxazin-4-one compound is the preparation of insecticide 3-bromo-N-[4-chloro-2-methyl- 6-[(methylamino)formyl]phenyl]-1-(3-chloro-2-pyridyl)-1H-pyrazole-5-carboxamide (Chlorantraniliprole, chlorantraniliprole) and other anthranilamides important intermediates of compounds. WO 2004 / 011447 A2, WO 03 / 015519 A1 and WO 2006 / 023783 Al disclose the preparation of 2-[1H-pyrazol-5-yl]-4H-3,1-benzoxazin-4-one compounds method. According to the prior art, 2-[1H-pyrazol-5-yl]-4H-3,1-benzoxazin-4-one compounds need to be prepared through three steps of oxidation, hydrolysis and coupling, the reaction formula as follows: [0003] [0004] In the formula: [0005] X is selected from Cl or Br; [0006] R 1 from C 1 -C 4 alkyl; [0007...

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): C07D413/14
Inventor 吴鸿飞李斌杨辉斌关爱莹欧阳津
Owner 中国中化股份有限公司