Method for synthesizing 2, 6-diaminotoluene

A technology of diaminotoluene and nitrotoluene, which is applied in the field of synthesizing 2,6-diaminotoluene, can solve the problems of high reaction temperature, equipment corrosion, and low yield, and achieve good reaction selectivity, less by-products, and high yield. high rate effect

Active Publication Date: 2015-06-24
ZHEJIANG DINGLONG TECH
View PDF4 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Among them, the yield of 2,6-dinitrotoluene is about 45% through the two-step reaction of trinitrotoluene solvent reduction and diazo deamination method, which is low, and the raw material trinitrotoluene is too dangerous, and there are Large potential safety hazard; the use of p-toluenesulfonic acid nitrification hydrolysis process has the problem of high reaction temperature and serious equipment corrosion. The nitrification temperature is 110-115 ° C, and the hydrolysis temperature is 170 ° C. The process corrodes the equipment seriously and the production safety is poor. ,

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 2, 6-diaminotoluene

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] (1) Reduction reaction: put a certain amount of 2-chloro-6-nitrotoluene 50g, Raney nickel 1g, dicyandiamide 0.05g, methanol 79g in a 250ml autoclave, seal the kettle, stir, nitrogen replacement three times, hydrogen replacement Three times, fill with hydrogen to 0.2MPa, take a sample after reacting at 50°C for 4 hours, until the raw material 2-chloro-6-nitrotoluene is completely reacted; filter the reaction solution to remove the catalyst, and recover methanol under reduced pressure to obtain 3-chloro-2-methanol The crude product of phenylaniline, the crude product obtained 37g of pure 3-chloro-2-methylaniline after vacuum distillation (yield 90%), GC>99%;

[0028] (2) Ammonolysis reaction: 20g of 3-chloro-2-methylaniline, 5g of cuprous chloride, 75g of 25% ammonia water, 2g of urea were put into a 250ml autoclave, the kettle was sealed, stirred, heated to 160°C, and the pressure was 2.3 MPa, take a sample after 20 hours of reaction until the raw material 3-chloro-2-met...

Embodiment 2

[0030] (1) Reduction reaction: drop into 2-chloro-6-nitrotoluene 50g in 250ml autoclave, Raney nickel 1g, dicyandiamide and morpholine compound 0.05g, the weight ratio of dicyandiamide and morpholine is 1 : 0.5, ethanol 79g, seal the kettle, stir, nitrogen replacement three times, hydrogen replacement three times, fill hydrogen to 0.1MPa, take a sample after reacting at 30°C for 4 hours, until the raw material 2-chloro-6-nitrotoluene is completely reacted; The catalyst was removed by filtration, and ethanol was recovered under reduced pressure to obtain a crude product of 3-chloro-2-methylaniline, which was 38 g (yield 92.5%) after vacuum distillation, GC>99%;

[0031] (2) Ammonolysis reaction: 20g of 3-chloro-2-methylaniline, 5g of cuprous oxide, 75g of 10% ammonia solution, 2g of benzaldehyde are put into a 250ml autoclave, the kettle is sealed, stirred, heated to 180°C, and the pressure is 3.0MPa, take a sample after 20 hours of reaction until the raw material 3-chloro-2-me...

Embodiment 3

[0033](1) Reduction reaction: drop 2-chloro-6-nitrotoluene 50g in 250ml autoclave, Raney nickel 1g, dicyandiamide and tributyl phosphate compound 0.05g, dicyandiamide and tributyl phosphate compound The weight ratio is 1:0.5, isopropanol 79g, seal the kettle, stir, replace with nitrogen three times, replace with hydrogen three times, fill with hydrogen to 0.2MPa, react at 40°C for 3 hours and take a sample until the raw material 2-chloro-6-nitrotoluene The reaction was complete; the reaction solution was filtered to remove the catalyst, and the isopropanol was recovered under reduced pressure to obtain the crude product of 3-chloro-2-methylaniline, which was 37 g (yield 90%) after vacuum distillation, GC>99%;

[0034] (2) Ammonolysis reaction: 20g of 3-chloro-2-methylaniline, 5g of copper oxide, 75g of 25% ammonia solution, 2g of urotropine are put into a 250ml autoclave, the kettle is sealed, stirred, heated to 150°C, and the pressure At 2MPa, take a sample after reacting for...

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 method for synthesizing 2, 6-diaminotoluene. The method comprises the following step: by using 2-chlorine-6-nitrotoluene as a raw material, carrying out reduction reaction and ammonolysis reaction to obtain 2, 6-diaminotoluene. The process is simple in synthesis route, easy to control the reaction and few in three wastes generated at the working segments, thereby meeting the green and environmental friendly requirements; and moreover, produced 2, 6-diaminotoluene is high in purity and excellent in quality, so that the method is an excellent industrial route.

Description

technical field [0001] The invention relates to a method for synthesizing 2,6-diaminotoluene. Background technique [0002] 2,6-diaminotoluene is an important chemical intermediate, which can be used in the synthesis of flexible polyurethane foam plastics, coatings, rubber and adhesives. 2,6-diaminotoluene can also be used as a dye intermediate. for the synthesis of various dyes. [0003] There have been many researches on the preparation method of 2,6-diaminotoluene. At present, the preparation method of 2,6-diaminotoluene is mainly prepared by reducing 2,6-dinitrotoluene. The specific method is to obtain 2,6-diaminotoluene by hydrogenation reduction of 2,6-dinitrotoluene in the presence of a catalyst; and the known and reported preparation method of 2,6-dinitrotoluene is trinitrotoluene reduction diazonium method , p-toluenesulfonic acid nitration hydrolysis method, toluene nitration mixture separation method three methods. Among them, the yield of 2,6-dinitrotoluene is...

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): C07C211/51C07C209/10
Inventor 秦振伟刘琛施云龙潘志军朱书荣朱翼鸣
Owner ZHEJIANG DINGLONG TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap