Synthesis process of 4-amino-6-hydroxybenzyl bromide

The technology of benzyl hydroxybromide and synthesis process is applied in the field of synthesis technology of photoinitiator, and can solve the problems of toxicity of photoinitiator and its photolysis products, low jumping efficiency between initiator systems, low molar extinction coefficient, etc., Achieve the effect of highlighting the photo-initiated activity, low cost, and simplifying the process operation process

Inactive Publication Date: 2020-09-15
XIANTAO XIANSHENG FINE CHEM
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The cost of existing photoinitiators is high, and the price is relatively expensive. The photoinitiators and their photolysis products are more toxic, not friendly to the environment, and the stability is not good enough, so they cannot be stored for a long time. In addition, the existing photoinitiators still have mole The extinction coefficient is not high, the intersystem crossing efficiency of the initiator is not high, and the initiation efficiency is low, etc.

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
  • Synthesis process of 4-amino-6-hydroxybenzyl bromide

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] A kind of 4-amino-6-hydroxyl benzyl bromide synthetic technique, comprises the following steps:

[0022] A. Hydrogenation reaction: put 400 parts of 5-nitro-o-cresol, 0.5 parts of PdC catalyst and 2000 parts of methanol into the autoclave, replace it with hydrogen three times, fill it with 1.0MPa hydrogen and set the temperature to 66 °C, Start to stir and heat up, and circulate the cooling water through the stirring sleeve. During the hydrogenation reaction, when the detection pressure drops to 0.5-0.6MPa, it is time to replenish the hydrogen pressure to 1.0MPa. After repeating this operation 4 times, when the pressure drops to 0.8MPa , add hydrogen once again, continue to react for 3 hours after repeating twice, the reduction reaction is basically completed, and the crude product of 5-amino-o-cresol is obtained, and the crude product of 5-amino-o-cresol is sucked out by a vacuum pump, and the crude product of 5-amino-o-cresol is Carry out cooling and sampling, and det...

Embodiment 2

[0027] A kind of 4-amino-6-hydroxyl benzyl bromide synthetic technique, comprises the following steps:

[0028] A. Hydrogenation reaction: put 400 parts of 5-nitro-o-cresol, 0.8 parts of PdC catalyst and 2500 parts of methanol into the autoclave, replace it with hydrogen three times, fill it with 1.0 MPa hydrogen and set the temperature to 66 °C, Start to stir and heat up, and circulate the cooling water through the stirring shaft sleeve. During the hydrogenation reaction, when the detection pressure drops to 0.5-0.6MPa, it is time to replenish the hydrogen pressure to 1.0MPa. After repeating this operation 5 times, when the pressure drops to 0.8MPa , add hydrogen once again, continue to react for 4 hours after repeating twice, and the reduction reaction is basically completed to obtain the crude product of 5-amino-o-cresol. Carry out cooling and sampling, and detect that the conversion rate of raw materials is greater than 99.5%;

[0029] B. Pressure filtration and decoloriz...

Embodiment 3

[0033] A kind of 4-amino-6-hydroxyl benzyl bromide synthetic technique, comprises the following steps:

[0034] A. Hydrogenation reaction: Put 400 parts of 5-nitro-o-cresol, 1.0 parts of PdC catalyst and 3000 parts of methanol into the autoclave, replace it with hydrogen three times, fill it with 1.0 MPa hydrogen and set the temperature to 66 ° C, Start to stir and heat up, and circulate the cooling water through the stirring shaft sleeve. During the hydrogenation reaction, when the detection pressure drops to 0.5-0.6MPa, it is time to replenish the hydrogen pressure to 1.0MPa. After repeating this operation 5 times, when the pressure drops to 0.8MPa , add hydrogen once again, continue to react for 5 hours after repeating twice, the reduction reaction is basically completed, and the crude product of 5-amino-o-cresol is obtained, and the crude product of 5-amino-o-cresol is sucked out by a vacuum pump, and the crude product of 5-amino-o-cresol is Carry out cooling and sampling,...

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

A synthesis process of 4-amino-6-hydroxybenzyl bromide comprises the following steps: adding 5-nitroo-cresol, a PdC catalyst and methanol into a high-pressure kettle, using hydrogen for replacement for three times, 1.0 MPa hydrogen is introduced, the temperature is set to be 66 DEG C, stirring and heating are started, circulating cooling water is introduced into a stirring shaft sleeve, then carrying out filter pressing, decolorizing, synthesizing 4-amino-6-hydroxybenzyl bromide, cooling a 4-amino-6-hydroxybenzyl bromide crude product, carrying out temperature reduction filter pressing, washing the obtained filter cake with water, and drying the filter cake to obtain the finished product. The 4-amino-6-hydroxybenzyl bromide has the advantages of low cost, outstanding photo-initiation activity, storage stability, low toxicity, small yellowing index of the adhesive film and favorable deep curing, and is beneficial to thorough curing of the thick film. In a contrast test, the photo-initiation efficiency is 3-6 times higher than that of a 2% photo-initiator 651. The product is subjected to hydrogenation reaction and synthesis reaction, the technological operation process is simplified,wastewater and waste gas generated in the reaction process are recycled, the environment is protected, industrial production is promoted, the production efficiency is improved, and the obtained product is high in quality and superior to imported products.

Description

technical field [0001] The invention relates to the field of synthesis technology of photoinitiators, in particular to a synthesis technology of 4-amino-6-hydroxybenzyl bromide. Background technique [0002] In the photocuring system, including UV glue, UV coating, UV ink, etc., after receiving or absorbing external energy, it undergoes chemical changes and decomposes into free radicals or cations, thereby initiating polymerization. All substances that can generate free radicals and further initiate polymerization by light are collectively called photoinitiators. After some monomers are illuminated, they absorb photons to form an excited state M*: M+hv→M*; the excited active molecules undergo homolysis to generate free radicals: M*→R·+R′·, which in turn initiates monomer polymerization. produce polymers. [0003] Radiation curing technology is an energy-saving and environmentally friendly new technology. Ultraviolet light (UV) and electron beam (EB), infrared light, visibl...

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 Applications(China)
IPC IPC(8): C07C213/02C07C213/10C07C213/08C07C215/76C08F2/48C09D11/101
CPCC07C213/02C07C213/08C07C213/10C08F2/48C09D11/101C07C215/76
Inventor 邵新华何正江王荣洲徐保华程永进
Owner XIANTAO XIANSHENG FINE CHEM
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