Method for synthesizing 2,2-dimethyl cysteamine hydrochloride

A technology of dimethylcysteine ​​hydrochloride and dimethyl, which is applied in the field of synthesizing 2,2-dimethylcysteine ​​hydrochloride, can solve the problem of harsh chlorination and reduction reaction conditions and high reagent prices. It is suitable for industrial production and other problems, and achieves the effects of low requirements for reaction equipment, shortened reaction time, and mild reaction conditions

Active Publication Date: 2016-10-12
ZHEJIANG YANGFAN NEW MATERIALS
View PDF3 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The process route has harsh conditions for chlorination and reduction reactions, and the price of reagents is relatively high, which is not suitable for industrial production.

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 2,2-dimethyl cysteamine hydrochloride
  • Method for synthesizing 2,2-dimethyl cysteamine hydrochloride
  • Method for synthesizing 2,2-dimethyl cysteamine hydrochloride

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0042]

[0043] Add ammonia water (68.0 g) and formaldehyde aqueous solution (113.6 g) into a three-necked flask, raise the temperature to 50-55° C., and add dimethylsulfide (44.0 g) dropwise. After the dropwise addition was completed, the reaction was incubated for 5 hours. The reaction solution was left to separate and separated, the water layer was discarded, the organic layer was collected, and the low boilers were removed under reduced pressure to obtain a colorless liquid, and then the crude product was distilled under reduced pressure to obtain 26.3 g of 5,5-dimethylthiazolidine with a yield of 45.0%. Content 99.0%.

[0044] 1HNMR (CDCl3, 400MHz) δ: 4.31(m, 2H), 2.38(s, 1H), 2.05(m, 2H), 1.45(s, 6H).

[0045] MS: [M+1]+=118.2

[0046]

[0047] Add the above-mentioned 5,5-dimethylthiazolidine and concentrated hydrochloric acid (120.5g) into a three-necked flask in turn, raise the temperature to 95°C for reaction, and at the same time distill off the low boilers u...

Embodiment 2

[0051]

[0052]Ammonia water (68.0 g) and acetone (43.5 g) were added into a three-necked flask, the temperature was raised to 50-55° C., and dimethylsulfide (44.0 g) was added dropwise. After the dropwise addition was completed, the reaction was incubated for 5 hours. The reaction solution was allowed to stand for stratification, the water layer was discarded, the organic layer was collected, and the low boilers were removed under reduced pressure to obtain a colorless liquid, and then the crude product was distilled under reduced pressure to obtain 69.2 g of 2,2,5,5-tetramethylthiazolidine. The rate is 95.2%, and the content is 97.0%.

[0053] 1HNMR (CDCl3, 400MHz) δ: 3.02(s, 2H), 2.63(s, 1H), 1.59(s, 6H), 1.44(s, 6H).

[0054] MS: [M+1]+=145.9

[0055]

[0056] Add the above-mentioned 2,2,5,5-tetramethylthiazolidine and concentrated hydrochloric acid (255.0g) into a three-necked flask in turn, raise the temperature to 95°C for reaction, and at the same time distill ...

Embodiment 3

[0060]

[0061] Add ammonia water (68.0 g) and butanone (54.0 g) into a three-necked flask, raise the temperature to 50-55° C., and add dimethylsulfide (44.0 g) dropwise. After the dropwise addition was completed, the reaction was incubated for 5 hours. The reaction solution was allowed to stand for stratification, the water layer was discarded, the organic layer was collected, and the low boilers were removed under reduced pressure to obtain a colorless liquid, and then the crude product was distilled under reduced pressure to obtain 2,5,5-trimethyl-2-ethylthiazolidine 73.4 g, yield 92.3%, content 97.3%.

[0062] 1HNMR (CDCl3, 400MHz) δ: 3.08-2.93(m, 2H), 2.56(s, 1H), 1.92-1.71(m, 2H), 1.53(s, 3H), 1.45(s, 3H), 1.39(s , 3H), 1.01(t, J=7.6Hz, 3H)

[0063] MS: [M+1]+=160.2

[0064]

[0065] Add the above-mentioned 2,5,5-trimethyl-2-ethylthiazolidine and concentrated hydrochloric acid (296.7g) into a three-necked flask in turn, raise the temperature to 95°C for reaction...

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 2,2-dimethyl cysteamine hydrochloride. The method comprises the steps that ketone or aldehyde, ammonium hydroxide and dimethyl ethylene sulfide are subjected to ring closing to obtain 5,5-dimethyl-2-substitued thiazolidine, and the 5,5-dimethyl-2-substitued thiazolidine is subjected to ring opening under the effect of hydrochloric acid to obtain 2,2-dimethyl cysteamine hydrochloride. The method has the advantages that a midbody does not need to be purified and can be put to a next reaction only through simple liquid separation operation, no phenylhydrazine is adopted in a reaction, the reaction time is greatly shortened, and the capacity is greatly improved. The raw materials of the reaction are easy to obtain, simple unit operations are adopted in the technology, the requirement for reaction equipment is low, the reaction conditions are mild, the yield and content are high, and the method is suitable for industrial production, and the content of the 2,2-dimethyl cysteamine hydrochloride is higher than 99%.

Description

technical field [0001] The invention relates to the technical field of organic synthesis, in particular to a method for synthesizing 2,2-dimethylcysteine ​​hydrochloride. Background technique [0002] 2,2-Dimethylcysteine ​​hydrochloride is an important intermediate of warnemulin hydrochloride. Warnemulin hydrochloride is a new generation of pleuromutilin semi-synthetic antibiotics, which belongs to diterpenes. Bacteroids belong to the same class of drugs and are antibiotics for animals. It is mainly used to prevent and treat mycoplasma disease and Gram-positive bacterial infection in pigs, cattle, sheep and poultry. It has the characteristics of broad antibacterial spectrum, strong antibacterial activity, excellent pharmacokinetic characteristics, low residue and high safety. [0003] Its preparation method is reported in the literature at present, specifically as follows: [0004] Patent CN102432510A discloses a synthetic method of 2,2-dimethylcysteine ​​hydrochloride: ...

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): C07C319/02C07C323/25C07D277/04
CPCC07C319/02C07D277/04C07C323/25
Inventor 汤文杰沈小明吴红辉樊彬
Owner ZHEJIANG YANGFAN NEW MATERIALS
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