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

Method for synthesizing 4-methyl-2-benzothiazolehydrazine

A technology of benzothiazole and methylphenylthiourea, which is applied in the field of medicine, can solve the problems of high cost of starting raw materials, low product purity, and difficult product separation, achieving good social and economic benefits, and simple process operation , good quality effect

Active Publication Date: 2020-06-26
HUBEI KECY CHEM
View PDF12 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The synthetic method of 4-methyl-2 hydrazinophenprothiazole mainly contains following two kinds at present: 1, take substituted anilide as starting raw material, through substitution reaction with phosphorus pentasulfide, generate N-o-methylphenylthiourea, then The cyclization reaction occurs under the condition of passing chlorine, and then reacts with hydrazine hydrate to obtain the target product. The starting material cost used in this reaction route is high, not easy to obtain, and there is a problem of product separation difficulty; 2. Starting with o-toluidine Raw materials, first add reaction with ammonium thiocyanate to generate N-o-methylphenylthiourea, then undergo ring closure reaction under the catalysis of chlorine gas, and finally perform nucleophilic substitution with hydrazine hydrate to generate 4-methyl-2 -hydrazinobenzothiazole
The current existing 4-methyl-2hydrazinobenzothiazole synthesis technologies all have the problems of low reaction efficiency and low product purity.

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 synthesizing 4-methyl-2-benzothiazolehydrazine
  • Method for synthesizing 4-methyl-2-benzothiazolehydrazine
  • Method for synthesizing 4-methyl-2-benzothiazolehydrazine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0058] 1. Synthesis of o-methylphenylthiourea: put 1477Kg o-toluidine in a 5000L reactor, add 1830Kg of pre-configured 42% sulfuric acid, add 1336Kg of sodium thiocyanate under stirring, turn on steam heating, and reflux for 4 hours , cooling, discharging and centrifuging, washing the filter cake with water until neutral, and drying the filter cake to obtain 1410Kg of o-methylphenylthiourea.

[0059] 2, the synthesis of 4-methyl-2-aminobenzothiazole: add 600Kg water in 3000L reactor, then the o-methylphenylthiourea obtained in the previous step reaction is put into reactor, add catalyst sodium bromide 28Kg, control The temperature is 25-30°C, react for 6 hours, cool, discharge and centrifuge, and dry the filter cake to obtain 1280Kg of 4-methyl-2-aminobenzothiazole.

[0060] 3. Synthesis of 4-methyl-2-hydrazinobenzothiazole: Add 40% hydrazine hydrate 1076Kg in a 3000L reactor, put the 4-methyl-2-aminobenzothiazole obtained in the previous step into the reactor, and stir Next,...

Embodiment 2

[0062] 1. Synthesis of o-methylphenylthiourea: put 1477Kg o-toluidine into 5000L reaction, add 2560Kg of pre-configured 30% sulfuric acid, add 1470Kg of sodium thiocyanate under stirring, turn on steam heating, reflux reaction for 4 hours, Cool, discharge and centrifuge, wash the filter cake with water until neutral, and dry the filter cake to obtain 1420Kg of o-methylphenylthiourea.

[0063] 2, the synthesis of 4-methyl-2-aminobenzothiazole: add 800Kg water in 3000L reactor, then the o-methylphenylthiourea gained in the previous step reaction is dropped into reactor, add catalyst calcium bromide 29Kg, control The temperature is 20-30 degrees, react for 6 hours, cool, discharge and centrifuge, and dry the filter cake to obtain 1210Kg of 4-methyl-2-aminobenzothiazole.

[0064] 3. Synthesis of 4-methyl-2-hydrazinobenzothiazole: Add 80% hydrazine hydrate 1050Kg in a 3000L reactor, put the 4-methyl-2-aminobenzothiazole obtained in the previous step into the reactor, and stir , tu...

Embodiment 3

[0066] 1. Synthesis of o-methylphenylthiourea: put 1605Kg o-toluidine into 5000L reaction, add 2500Kg of pre-configured 30% sulfuric acid, add 1337Kg of sodium thiocyanate under stirring, turn on steam heating, reflux reaction for 6 hours, Cool, discharge and centrifuge, wash the filter cake with water until neutral, and dry the filter cake to obtain 2270Kg of o-methylphenylthiourea.

[0067] 2, the synthesis of 4-methyl-2-aminobenzothiazole: add 1200Kg water in 5000L reactor, then put the o-methylphenylthiourea gained in last step reaction into reactor, add catalyst sodium bromide 50Kg, control The temperature is 40-50 degrees, react for 6 hours, cool, discharge and centrifuge, and dry the filter cake to obtain 2050Kg of 4-methyl-2-aminobenzothiazole.

[0068] 3. Synthesis of 4-methyl-2-hydrazinobenzothiazole: Add 80% hydrazine hydrate 1570Kg in a 5000L reactor, put 4-methyl-2-aminobenzothiazole obtained in the previous step into the reactor, and stir Next, turn on the heati...

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 method for synthesizing 4-methyl-2-benzothiazolehydrazine. The method comprises the following steps: carrying out synthesis reaction on o-toluidine and thiocyanate in acid toobtain o-tolylthiourea; carrying out a synthesis reaction on the o-tolylthiourea and a catalyst in water to obtain 2-amino-4-methylbenzothiazole; and carrying out a synthesis reaction on the 2-amino-4-methylbenzothiazole in hydrazine hydrate, so as to obtain the 4-methyl-2-benzothiazolehydrazine. The method for synthesizing the 4-methyl-2-benzothiazolehydrazine, provided by the invention, is simple to operate, less in three wastes, capable of repeatedly applying wastewater, high in product content, good in quality and suitable for industrial mass production.

Description

technical field [0001] The invention relates to the technical field of medicine, in particular to a method for synthesizing 4-methyl-2-hydrazinobenzothiazole. Background technique [0002] 4-Methyl-2-hydrazinobenzothiazole is an important intermediate of the pesticide tricyclazole, which is one of the main pesticides for the control of rice blast at present. Ecologically sound pesticides. 4-Methyl-2-hydrazinobenzothiazole is an important pesticide intermediate widely used all over the world. The research on its synthetic structure and pharmacological activity has always attracted much attention. The synthetic method of 4-methyl-2 hydrazinophenprothiazole mainly contains following two kinds at present: 1, take substituted anilide as starting raw material, through substitution reaction with phosphorus pentasulfide, generate N-o-methylphenylthiourea, then The cyclization reaction occurs under the condition of passing chlorine, and then reacts with hydrazine hydrate to obtain ...

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): C07D277/82
CPCC07D277/82
Inventor 穆海平肖世军赵瑞先计平吴海荣贺才荣
Owner HUBEI KECY CHEM
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