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

A kind of preparation method of 2-amino-5-fluorobenzonitrile

The technology of fluorobenzonitrile and amino group is applied in the field of preparation of 2-amino-5-fluorobenzonitrile, which can solve the problems of high cost, unfavorable industrialized amplification, long route and the like, and achieves the effects of short route and low raw material price.

Active Publication Date: 2022-03-11
无锡双启科技有限公司
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In the above synthesis method, there are four steps in the process of synthesizing 2-amino-5-fluorobenzonitrile compound I. The route is long, and the last step is hydrogenation with palladium carbon, which is costly and unfavorable for industrial scale-up.

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
  • A kind of preparation method of 2-amino-5-fluorobenzonitrile
  • A kind of preparation method of 2-amino-5-fluorobenzonitrile
  • A kind of preparation method of 2-amino-5-fluorobenzonitrile

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] A preparation method of 2-amino-5-fluorobenzonitrile, said preparation method comprising the steps of:

[0029] (1) Add 142g (1mol) 2,5-difluorobenzaldehyde, 500ml dichloromethane, 83.4g (1.2mol) hydroxylamine hydrochloride, 202g (2mol) triethylamine to the reaction flask, and stir the reaction at 20°C after adding After 4 hours, the reaction was tracked by HPLC until the reaction of 2,5-difluorobenzaldehyde was complete; 1000ml of water was added to wash the organic layer, and the organic layer was concentrated to obtain 149.2g of compound III, with a molar yield of 95%.

[0030] (2) Add 78.5g (0.5mol) of compound III, 200ml of N,N-dimethylformamide, 153g (1mol) of phosphorus oxychloride to the reaction flask, stir at 80°C for 6 hours after the addition, and follow the reaction by HPLC until the compound III reacted completely; quenched into 1000ml of ice water, filtered and dried to obtain 59g of compound IV, molar yield: 85%.

[0031] (3) Add 41.7g (0.3mol) of compo...

Embodiment 2

[0035] A preparation method of 2-amino-5-fluorobenzonitrile, said preparation method comprising the steps of:

[0036] (1) Add 142g (1mol) 2,5-difluorobenzaldehyde, 500ml chloroform, 90.35g (1.3mol) hydroxylamine hydrochloride, 202g (2mol) triethylamine to the reaction flask, and stir at 30°C after adding After reacting for 2 hours, follow the reaction by HPLC until the reaction of 2,5-difluorobenzaldehyde is complete; add 1000ml of water to wash the organic layer, and concentrate the organic layer to obtain 146g of compound III, with a molar yield of 93%.

[0037] (2) Add 78.5g (0.5mol) of compound III, 200ml of N,N-dimethylformamide, 191.3g (1.25mol) of phosphorus oxychloride to the reaction flask, stir at 60°C for 2 hours after the addition, and follow the reaction by HPLC Until compound III reacted completely; quenched into 1000ml of ice water, filtered and dried to obtain 61.2g of compound IV, molar yield: 88%.

[0038] (3) Add 41.7g (0.3mol) of compound IV and 100ml of ...

Embodiment 3

[0040] A preparation method of 2-amino-5-fluorobenzonitrile, said preparation method comprising the steps of:

[0041] (1) Add 142g (1mol) 2,5-difluorobenzaldehyde, 500ml ethyl acetate, 97.3g (1.3mol) hydroxylamine hydrochloride, 202g (2mol) triethylamine to the reaction flask, and stir at 40 degrees for 3 hours after adding , HPLC followed the reaction until the reaction of 2,5-difluorobenzaldehyde was complete; 1000ml of water was added to wash the organic layer, and the organic layer was concentrated to obtain 144.4g of compound III, with a molar yield of 92%.

[0042] (2) Add 78.5g (0.5mol) of compound III, 200ml of N,N-dimethylformamide, 229.5g (1.5mol) of phosphorus oxychloride to the reaction flask, stir at 40°C for 4 hours after the addition, and follow the reaction by HPLC Until compound III reacted completely; quenched into 1000ml of ice water, filtered and dried to obtain 64g of compound IV, molar yield: 92%.

[0043] (3) Add 41.7g (0.3mol) of compound IV and 100ml...

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 preparation method of 2-amino-5-fluorobenzonitrile. The specific steps of the preparation method are as follows: (1) using 2,5-difluorobenzaldehyde as a starting material, under the condition of triethylamine Condensation reaction occurs with hydroxylamine hydrochloride at the bottom to generate compound III; (2) compound III is dehydrated with phosphorus oxychloride to generate compound IV; (3) compound IV is subjected to ammonia amination to generate compound I; that is, the 2-amino-5- Fluorobenzonitrile. The yield of the preparation method of the present invention is higher.

Description

technical field [0001] The invention relates to the technical field of medicine and chemical industry, in particular to a preparation method of 2-amino-5-fluorobenzonitrile. Background technique [0002] 2-amino-5-fluorobenzonitrile is a class of key intermediates, and WO2006 / 129120 discloses the following route for the synthesis of 2-amino-5-fluorobenzonitrile compound I: [0003] [0004] In the above synthesis method, there are four steps of reaction in the process of synthesizing 2-amino-5-fluorobenzonitrile compound I, the route is long, and the last step of reduction is hydrogenation with palladium carbon, which has high cost and is not conducive to industrial scale-up production. Contents of the invention [0005] In view of the above-mentioned problems in the prior art, the applicant of the present invention provides a preparation method of 2-amino-5-fluorobenzonitrile. The production rate of the preparation method of the present invention is higher. [0006] ...

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): C07C253/30C07C255/58
CPCC07C253/30C07C253/00C07C249/08C07C255/58C07C255/50C07C251/48
Inventor 张国强王昌军秦英
Owner 无锡双启科技有限公司