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

Preparation method of 2,4,5-trifluorobenzyl chloride

A technology of trifluorobenzyl chloride and trifluorobenzene is applied in the field of preparation of pharmaceutical intermediates, can solve problems such as low economy, difficult industrialization, unfriendly environment, etc., and achieves cheap and easily available raw materials, mild reaction conditions, and easy industrialization. Effect

Active Publication Date: 2011-04-20
ZHEJIANG YONGTAI TECH CO LTD
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Chinese patent 200510030162.0 reported that 1,2,4-trifluorobenzene uses chlorosulfonic acid and zinc chloride as chlorinating agent, and reacts with paraformaldehyde through Blanc to prepare 2,4,5-trifluorobenzyl chloride, the method The yield is low, the economy is not high, and the environment is not friendly
Chinese patent 200710039502.5 reports that chloromethyl ethers and Lewis acids are used as chlorinating agents to prepare 2,4,5-trifluorobenzyl chloride. The price of chloromethyl ethers used is relatively high, resulting in high industrial production costs and difficult industrialization.

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 2,4,5-trifluorobenzyl chloride
  • Preparation method of 2,4,5-trifluorobenzyl chloride
  • Preparation method of 2,4,5-trifluorobenzyl chloride

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Add 100ml of 98% sulfuric acid into a 250ml four-necked reaction flask, cool down to 20°C, add 21.3g of paraformaldehyde (equivalent to 0.71mol of monomeric formaldehyde), 44.8g of sodium chloride (0.766mol), and finally add 1,2 , 50.8 g (0.385 mol) of 4-trifluorobenzene. After the addition was completed, the reaction was carried out at 40° C. for 10 hours. Pour the reaction solution into ice water, stir for 30 minutes after the addition, separate the organic layer, wash until neutral, dry and then distill under reduced pressure to obtain 58.8g of 2,4,5-trifluorobenzyl chloride with a content of 99.8% , yield 84.7%. In the accompanying drawings figure 1 Is the hydrogen spectrum spectrum of 2,4,5-trifluorobenzyl chloride:.

[0022] NMR data analysis:

[0023] 1H-NMR (CDCl3, 500Hz) δ: 4.56 (s, 2H), 6.95 (m, 1H), 7.26 (m, 1H).

Embodiment 2

[0025] According to Example 1, 57.1 g (0.766 mol) of potassium chloride was used instead of sodium chloride to obtain 55.1 g of 2,4,5-trifluorobenzyl chloride with a content of 98.2% and a yield of 79.3%.

Embodiment 3

[0027] According to Example 1, 100 ml of 30% hydrochloric acid was used instead of sulfuric acid to obtain 47.6 g of 2,4,5-trifluorobenzyl chloride with a content of 98.6% and a yield of 68.5%.

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 the field of the preparation method of the pharmaceutical intermediate, in particular to the field of the preparation method of 2,4,5-trifluorobenzyl chloride. The method adopts 1,2,4-trifluorobenzene and paraformaldehyde to react in the presence of chlorinating agent and obtain 2,4,5-trifluorobenzyl chloride. The content of 2,4,5-trifluorobenzyl chloride obtained by purification is above 99.8%. The preparation method of 2,4,5-trifluorobenzyl chloride has cheap and accessible raw material and mild reaction conditions, is economic and environmentally friendly and is easy to realize industrialization; in addition, the product purity and yield are high and the product fully meets the operating requirements of the pharmaceutical intermediate.

Description

technical field [0001] The invention relates to the field of preparation methods of pharmaceutical intermediates, in particular to the field of preparation methods of 2,4,5-trifluorobenzyl chloride. Background technique [0002] 2,4,5-Trifluorobenzyl chloride is a key intermediate in the synthesis of new drugs for the treatment of diabetes. Chinese patent 200510030162.0 reported that 1,2,4-trifluorobenzene uses chlorosulfonic acid and zinc chloride as chlorinating agent, and reacts with paraformaldehyde through Blanc to prepare 2,4,5-trifluorobenzyl chloride, the method The yield is low, the economy is not high, and the environment is not friendly. Chinese patent 200710039502.5 reports that chloromethyl ethers and Lewis acids are used as chlorinating agents to prepare 2,4,5-trifluorobenzyl chloride. The price of chloromethyl ethers used is relatively high, resulting in high industrial production costs and difficulty in industrialization. Contents of the invention [0003...

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): C07C25/13C07C17/32
Inventor 钟建新邵鸿鸣
Owner ZHEJIANG YONGTAI TECH CO LTD