Synthesis method of 2-bromo-5-methoxyphenol

A technology of methoxyphenol and synthesis method, which is applied in the field of synthesis of chemical intermediates - 2-bromo-5-methoxyphenol, can solve problems such as difficult separation, low yield, and difficult post-processing, and achieve post-processing Simple treatment, high conversion rate, and the effect of reducing the formation of isomers

Inactive Publication Date: 2019-10-11
杭州迈世腾药物科技有限公司
View PDF7 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

On the one hand, although this method is simple to operate, the yield is relatively low, only about 60%; It is inevitable to generate 4-bromo-3-methoxyphenol isomers, and the properties of 4-bromo-3-methoxyphenol and 2-bromo-5-methoxyphenol are very similar, and it is very difficult to separate them. Difficult, that is, the post-processing of this method is more difficult

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 method of 2-bromo-5-methoxyphenol
  • Synthesis method of 2-bromo-5-methoxyphenol

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0047] Embodiment 1, a kind of preparation method of 2-bromo-5-methoxyphenol, take 3-methoxyphenol as raw material, carry out the following steps successively:

[0048] 1), 1.00g (8.06mmol) of 3-methoxyphenol, 4.0mL N,N-dimethylformamide (analytical grade) and 1.46g (9.67mmol) of tert-butyldimethylsilyl chloride were put into 50mL In a three-necked flask; under magnetic stirring, 0.87 g (12.80 mmol) of imidazole was added; at room temperature, magnetic stirring was performed for 1 h.

[0049] After the reaction, use saturated sodium bicarbonate solution (about 15.0 mL) to adjust the pH of the reaction solution to 8, then extract with ethyl acetate (30.0 mL), and add anhydrous sodium sulfate (about 5 g) to the resulting extraction phase to dry After filtration, the resulting filtrate was distilled off under reduced pressure (pressure of -0.1MPa) to remove the extractant (ethyl acetate) to obtain the intermediate 1-[[(1,1-dimethylethyl)dimethylsilyl] Oxy]-3-methoxybenzene 1.85 ...

Embodiment 2

[0057] Embodiment 2, a kind of preparation method of 2-bromo-5-methoxyphenol, take 3-methoxyphenol as raw material, carry out the following steps successively:

[0058] 1), 1.00g (8.06mmol) of 3-methoxyphenol, 7.0mL N,N-dimethylformamide (analytical grade) and 1.82g (12.09mmol) of tert-butyldimethylsilyl chloride were put into 50mL In a three-necked flask; 0.87 g (12.80 mmol) of imidazole was added under magnetic stirring; at room temperature, magnetic stirring was carried out for 2 hours.

[0059] The post-treatment after the reaction is the same as step 1) of Example 1; 1.88 g of the intermediate (same as Example 1) was obtained, with a yield of 97.9%.

[0060] 2), put 1.88g (7.89mmol) of all intermediates obtained in step 1) into a 50mL three-necked flask, then add 15.0mL of dichloromethane into the flask, and finally put N-bromosuccinyl in batches under magnetic stirring Imine 1.38g (7.73mmol); magnetic stirring reaction at room temperature for 3h.

[0061] The post-trea...

Embodiment 3

[0064] Embodiment 3, a kind of preparation method of 2-bromo-5-methoxyphenol, take 3-methoxyphenol as raw material, carry out the following steps successively:

[0065] 1) Put 1.00g (8.06mmol) of 3-methoxyphenol, 4.0mL cyclohexane (analytical grade) and 0.76g (9.68mmol) of acetyl chloride into a 50mL three-necked flask; at room temperature, magnetically stir the reaction for 3h.

[0066] For post-processing after the reaction, refer to step 1) of Example 1; 1.29 g of intermediate 3-methoxyphenyl acetate was obtained, with a yield of 96.6%.

[0067] 2), 1.29g (7.79mmol) of all the intermediate 3-methoxyphenylacetate obtained in step 1) was dropped into a 50mL three-necked flask, then 12.9mL of acetonitrile was added to the flask, and finally N was added in batches under magnetic stirring. -Bromosuccinimide 1.36g (7.63mmol); at 40°C, react with magnetic stirring for 4h.

[0068] For post-processing after the reaction, refer to step 2) of Example 1; 1.71 g of 2-bromo-5-methoxyph...

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 synthesis method of 2-bromo-5-methoxyphenol. According to the synthesis method, 3-methoxyphenol is taken as a raw material, firstly, the 3-methoxyphenol reacts with a protection reagent such as tert-butyldimethylsilyl chloride, acetyl chloride, acetic acid and acetic anhydride, and then hydroxide radicals are protected; then an obtained intermediate is subjected to a bromination reaction; finally, an obtained bromination product is de-protected to obtain the 2-bromo-5-methoxyphenol. The method has the advantages that the operation condition is mild and safe, aftertreatment is simple, and the conversion rate is high. The yield achieved by means of the synthesis method is far higher than that of an existing direct bromination method, and aftertreatment is relativelysimple.

Description

technical field [0001] The invention relates to a synthetic method of a chemical intermediate - 2-bromo-5-methoxyphenol. Background technique [0002] 2-Bromo-5-methoxyphenol, which has the molecular formula C 7 h 7 BrO 2 , its structural formula is as follows: [0003] [0004] The pure product of 2-bromo-5-methoxyphenol is a white crystal, which is an important intermediate in organic synthesis and is widely used in medicine and pesticides. [0005] The main method of producing 2-bromo-5-methoxyphenol reported so far: [0006] Using 3-methoxyphenol as the starting material, 2-bromo-5-methoxyphenol can be directly obtained through bromination reaction. On the one hand, although this method is simple to operate, the yield is relatively low, only about 60%; It is inevitable to generate 4-bromo-3-methoxyphenol isomers, and the properties of 4-bromo-3-methoxyphenol and 2-bromo-5-methoxyphenol are very similar, and it is very difficult to separate them. Difficult, that...

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): C07C41/26C07C43/23
CPCC07C41/26C07C67/14C07C67/287C07F7/1804C07F7/188C07C43/23C07C69/157C07C69/63
Inventor 靳浩钱超高卓
Owner 杭州迈世腾药物科技有限公司
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