Method for asymmetrical hydrogen transfer of alpha-imino keton for synthesizing chirality salbutamol

A technology for salbutamol and iminone, which is applied in the field of synthesis of chiral-beta amino alcohol compounds and achieves the effects of mild reaction conditions, simple processing and simple post-processing

Inactive Publication Date: 2006-02-15
EAST CHINA NORMAL UNIV
View PDF2 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The catalyst has been successfully used in the asymmetric hydrogen transfer reaction of aromatic ketones, substituted aromat...

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 asymmetrical hydrogen transfer of alpha-imino keton for synthesizing chirality salbutamol
  • Method for asymmetrical hydrogen transfer of alpha-imino keton for synthesizing chirality salbutamol
  • Method for asymmetrical hydrogen transfer of alpha-imino keton for synthesizing chirality salbutamol

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] The first step is the preparation of methyl 5-(1,1-dihydroxy)-acetyl-2-hydroxybenzoate.

[0028] Add 75ml dimethyl sulfoxide (DMSO) in the 250ml three-necked bottle, 19.5g (0.1mol) methyl 5-acetyl salicylate, under room temperature, hydrobromic acid (HBr) 28ml (40%, 0.2mol, 2.0 eq) was added slowly, and the dropwise addition was completed in 40 minutes. The reaction solution was heated to 65° C., and reacted for about 20 hours. TLC detected that the raw material 5-acetyl salicylate methyl ester disappeared, and the reaction solution was slowly poured into 200 ml of ice water, and stirred for 30 Minutes, filtered, the solid was washed 3 times with 25ml of ice water, and vacuum-dried at room temperature to obtain 20.3g of the product 5-(1,1-dihydroxy)-acetyl-2-hydroxybenzoic acid methyl ester, with a yield of 90%. After further purification, it can be directly put into the next reaction.

[0029] The second step is the preparation of methyl 5-((1,1-dimethylethyl)imino)acet...

Embodiment 2

[0036] The first and second steps are the same as in Example 1.

[0037] The third step is the preparation of (S)-5-[2-[(1,1-dimethylethyl)amino]-1-hydroxyethyl]-2-hydroxybenzoic acid methyl ester.

[0038] Under nitrogen protection, 0.26g (1mmol) of the compound obtained in the second step, (R, R)-Ru-TsDPEN6.4mg (0.01mmol), Et 3 Dissolve N 0.69ml (5.0mmol) in 2.0ml DMF, add HCOOH 0.07ml (2.0mmol) slowly, stir at room temperature for 24 hours, pour the reaction solution into 5.0ml water, extract twice with 10ml ethyl acetate, anhydrous sodium sulfate Drying, solvent evaporation under reduced pressure, and column chromatography to obtain the product (S)-5-[2-[(1,1-dimethylethyl)amino]-1-hydroxyethyl]-2-hydroxybenzoic acid Methyl ester 0.13g, 96%ee, yield 48%.

[0039] The fourth step (S)-Salbutamol is: the preparation of (S)-2-(nitrogen-tert-butylamino)-1-(4-hydroxyl-3-hydroxymethylphenyl)ethanol

[0040] Under nitrogen protection condition, the product (S)-5-[2-[(1,1-dimeth...

Embodiment 3

[0042] The first, second and third steps are the same as in Example 1.

[0043] The fourth step is the preparation of (R)-Salbutamol: (R)-2-(nitrogen-tert-butylamino)-1-(4-hydroxyl-3-hydroxymethylphenyl)ethanol.

[0044] Under nitrogen protection condition, take by weighing the product 0.27g (1mmol) that the 3rd step makes, NaBH 4 95mg (2.5mmol), suspended in 10ml of anhydrous tetrahydrofuran (THF), slowly dropwise added 0.4ml of BF3.Et2O solution (content 47%, d, 1.13, 1.5mmol) at room temperature, and heated the reaction solution to 55°C after the dropwise addition React for 3 hours, drop to room temperature, drop methanol 4ml, then heat the reaction solution to 55°C for 1.5 hours, cool to room temperature, add N,N,N,N-tetramethylethylenediamine (TMEDA) 0.23ml ( 1.5mmol), stirred at room temperature for 6 hours and then filtered, the solvent was evaporated under reduced pressure, and the product (R)-Salbutamol was obtained by column chromatography was 0.18g, 98% ee, and th...

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

Disclosed is a method for asymmetrical hydrogen transfer of alpha-imino keton for synthesizing chirality salbutamol which comprises, using 5-acetyl methyl salicylate as raw material, oxidizing with oxidation agent into 5-(1,1-)dihydroxy)-acetyl-2-hydroxybenzoate, then reacting with tert-butylamine, obtaining alpha-imine ketone compound. Then using (S,S)-Ru-TsDPEN or (R,R)-Ru-TsDPEN as catalyst, subjecting the alpha-imine ketone compound to asymmetrical hydrogen migration in formylic acid, triethylamine and inert organic solvent system, thus obtaining the optically pure product of (R) or (S)-5-[2-[(1,1-dimethylethyl)amino]-1-ethoxyl]-2-hydroxybenzoate, finally deoxidizing the (R) or (S)-5-[2[(1,1-dimethylethyl)amino]-1-ethoxyl]-2-hydroxybenzoate to obtain the optically pure (R) or (S) chiral salbutamol.

Description

technical field [0001] The invention discloses a method for synthesizing chiral salbutamol by asymmetric hydrogen transfer of α-iminone ketone, relates to a new method for synthesizing optically pure-β amino alcohol compound salbutamol, and belongs to the technical field of chiral-β amino alcohol compound synthesis. Background technique [0002] Optically pure chiral aminoalcohols have shown increasing importance in medicinal and organic chemistry. In terms of medicinal chemistry, many aminoalcohol derivatives can be used as drugs, such as -βaminoarylethanol compounds are good medicines for the treatment of respiratory and cardiovascular diseases. A large number of medical practices have proved that only one optical isomer in racemic drugs has a better curative effect, and different enantiomers of chiral drugs often show different physiological activities. Therefore, for optically pure chiral β -Research on aminoarylethanol compounds is currently r...

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): C07C215/60C07C213/00
Inventor 肖元晶谭宙宏杨琍苹
Owner EAST CHINA NORMAL UNIV
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