Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of thiazafluron original medicine

A technology of tifluron technical and thiadiazole, which is applied in the field of synthesis of tifluron technical, can solve the problems of strict production equipment, inability to transport, and unreported synthesis process of tifluron, and achieve high purity and high yield rate effect

Inactive Publication Date: 2018-12-21
HEBEI UNIV OF TECH
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The structure of tifluron is shown in formula IV. In DE1816696, US4686294 and US4175081, 2-methylamino-5 trifluoromethyl-1,3,4-thiadiazole is reacted with methyl isocyanate. Synthesis of thiafluron and methyl isocyanate are flammable and highly toxic drugs, which have strict requirements on production equipment and cannot be transported
At present, there is no report on the synthesis process of tifluron in China

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
  • Preparation method of thiazafluron original medicine
  • Preparation method of thiazafluron original medicine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] Example 1: Add 2-methylamino-(5-trifluoromethyl)-1,3,4-thiadiazole (I) 128g (0.7mol) and 700ml toluene to a 2L reaction kettle, at 30°C 500ml of toluene containing 80g (0.84mol) of N-methylcarbamoyl chloride (II) was added dropwise, and the addition was completed after 2 hours. At this temperature, 81 g (0.8 mol) of anhydrous triethylamine was added dropwise, and the addition was completed within 1.5 hours. The reaction was incubated at this temperature for 1 h. Afterwards, the temperature was raised to 70° C., and the reaction was kept at this temperature for 4 hours. Lower the temperature and add 150ml of water at 60°C, and continue to cool down to 10°C. , stirred and incubated for 0.5h, filtered, dried, and dried to obtain 168g of 97% white product tifluron. Yield 97%, melting point 135-137 ℃ (HPLC, H 2 O:CH 3 OH=20:80).

Embodiment 2

[0027] Embodiment 2: Add 2-methylammonia-(5-trifluoromethyl)-1,3,4-thiadiazole (I) 18.3g (0.1mol) and 100ml toluene in 500mL reactor, at 30 °C, 100 ml of toluene containing 13 g (0.14 mol) of N-methylcarbamoyl chloride (II) was added dropwise, and the addition was completed within 2 hours. At this temperature, 11.2 g (0.11 mol) of anhydrous triethylamine was added dropwise, and the dropwise addition was completed in about 1.5 hours. The reaction was incubated at this temperature for 1 h. Afterwards, the temperature was raised to 75° C., and the reaction was kept at this temperature for 4 hours. Cool down at 60°C, add 50ml of water, continue to cool down to 10°C, keep warm for 0.5h, filter, dry, and dry to obtain 24.5g of 95% white product Teflon. Yield 97.5%, melting point 135-137 ℃ (HPLC, H 2 O:CH 3 OH=20:80).

Embodiment 3

[0028] Embodiment 3: Add 2-methylammonia-(5-trifluoromethyl)-1,3,4-thiadiazole (I) 36.6g (0.2mol) and 200ml toluene in 1000mL reactor, at 30 °C, 150 ml of toluene containing 22.5 g (0.24 mol) of N-methylcarbamoyl chloride (II) was added dropwise. , into N 2 The temperature was raised to 75°C, and the reaction was kept at this temperature for 4h. Cool down to below 60°C, slowly add 200ml of water, continue to cool down to 10-15°C, keep warm for 0.5h, filter, dry, and dry to obtain 44g of 97% white product Teflon. Yield 89%, melting point 135-137 ℃ (HPLC, H 2 O:CH 3 OH=20:80).

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 relates to a preparation method of a thiazafluron original medicine. The method comprises the following steps: dropwise adding an N-methylaminoformyl chloride solution into a 2-methyl ammonia-(5-trifluoromethyl)-1,3,4-thiadiazole solution; then introducing nitrogen after dropwise adding organic alkali; then after heating and cooling reactions, adding water to react; and filtering anddrying the solution to obtain a white solid thiazafluron. According to the preparation method, flammable and combustible methyl isocyanate which is unlikely to transport is not used, and a product which is high in yield and purity can be obtained without recrystallization.

Description

technical field [0001] The invention relates to the field of pesticide synthesis, in particular to a method for synthesizing the original drug of tifluron. Background technique [0002] As a herbicide, tifluron has changed its water solubility and biological activity due to the introduction of trifluoromethyl. Due to its stable carbon-fluorine bond and strong electron-withdrawing induction effect, trifluoromethyl plays an important role in the field of pharmaceuticals, especially in the field of pesticides. Therefore, tifluron has a good herbicidal effect. The general name of thiazafluron is thiazafluron, and its chemical name is N,N'-dimethyl-N-[5-(trifluoromethyl)-1,3,4-thiadiazol-2-yl]urea. The appearance of tifluron is white powder solid, melting point: 137-138 ℃. Teflon is excellent for controlling weeds in non-arable land, shrubs in pasture areas, and broadleaf weeds. [0003] [0004] The structure of tifluron is shown in formula IV. In DE1816696, US4686294 and...

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): C07D285/135
CPCC07D285/135
Inventor 高中良时荣超王瑾王子玉
Owner HEBEI UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com