Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Dimethyl cysteamine hydrochloride synthetic process

A technology of dimethyl cysteamine hydrochloride and dimethyl, which is applied in the field of synthesizing dimethyl cysteamine hydrochloride to reduce operating intensity, improve reaction yield and product content, and avoid the use of pressure vessels Effect

Inactive Publication Date: 2017-04-19
杭州扬帆化工科技有限公司
View PDF3 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0017] The present invention solves the shortcoming of above-mentioned existing synthetic method, provides a kind of technique of synthesizing dimethylcysteamine hydrochloride

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
  • Dimethyl cysteamine hydrochloride synthetic process
  • Dimethyl cysteamine hydrochloride synthetic process
  • Dimethyl cysteamine hydrochloride synthetic process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0048] 5,5-Dimethyl-2-isopropylthiazolidine (III) (79.5g), toluene (280g), phenylhydrazine (48.6g) and hydrochloric acid (700g) were added to the glass reactor in turn, heated to reflux , the reaction was incubated for 2 hours. Cool to room temperature, separate the water phase and extract it once with toluene, then add acetone (43.5g) to the water phase, adjust the pH to 10 with liquid caustic soda, stir at room temperature for 2 hours, extract twice with toluene, combine the organic phases, wash with water, remove Dissolved and distilled under reduced pressure to obtain 62.1 g of 2,2,5,5-tetramethylthiazolidine with a yield of 85.7% and a content of 97.0%.

[0049] 1H NMR (CDCl3, 400 MHz) δ: 3.02 (s, 2H), 2.63 (s, 1H), 1.59 (s, 6H), 1.44 (s, 6H).

[0050] MS: [M+1]+=145.9

[0051] The above-mentioned 2,2,5,5-tetramethylthiazolidine and concentrated hydrochloric acid (230.0g) were successively added to the there-necked flask, and the temperature was raised to 95° C. to reac...

Embodiment 2

[0055] 5,5-Dimethyl-2-isopropylthiazolidine (III) (79.5g), toluene (280g), phenylhydrazine (48.6g) and hydrochloric acid (700g) were added to the glass reactor in turn, heated to reflux , the reaction was incubated for 2 hours. The temperature was cooled to room temperature, the water phase was separated and extracted once with toluene, then methyl ethyl ketone (54.0 g) was added to the water phase, the pH was adjusted to 10 with liquid caustic soda, stirred at room temperature for 2 hours, extracted twice with toluene, combined with the organic phases and washed with water, Precipitated and distilled under reduced pressure to obtain 66.0 g of 2,5,5-trimethyl-2-ethylthiazolidine with a yield of 83.0% and a content of 97.0%.

[0056] 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)

[0057] MS: [M+1]+=160.2

[0058] The above-mentioned 2,5,5-trimethyl-2-ethylthiazolidine and concentrated hy...

Embodiment 3

[0062] 5,5-Dimethyl-2-isopropylthiazolidine (III) (79.5g), toluene (280g), phenylhydrazine (48.6g) and hydrochloric acid (700g) were added to the glass reactor in turn, heated to reflux , the reaction was incubated for 2 hours. Cool to room temperature, separate the water phase and extract it once with toluene, then add cyclohexanone (73.5g) to the water phase, adjust the pH to 10 with liquid alkali, stir at room temperature for 2 hours, extract twice with toluene, combine the organic phases and wash with water , precipitation, and distillation under reduced pressure to obtain 79.5 g of 2,2-dimethyl-1-thio-4-azaspiro[4.5]decane with a yield of 86% and a content of 96.6%.

[0063] 1HNMR(CDCl3, 400MHz)δ: 2.99(s, 2H), 2.56(s, 1H), 1.90-1.86(m, 2H), 1.76-1.70(m, 4H), 1.60-1.34(m, 9H), 1.31 -1.18(m,1H)

[0064] MS: [M+1]+=186.0

[0065] The above-mentioned 2,2-dimethyl-1-thio-4-azaspiro[4.5]decane and concentrated hydrochloric acid (351.0 g) were successively added to the three-...

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 dimethyl cysteamine hydrochloride synthetic process. The dimethyl cysteamine hydrochloride is synthesized by taking isobutyraldehyde as an initial raw material through reactions of condensation, reduction, ring opening and ring closing, and ring opening. The process has the beneficial effects as follows: by replacing ammonia gas with ammonium hydroxide in a condensation reaction, and by directly putting a sodium borohydride solution from a place below a liquid surface to a reaction system in a reduction reaction, the reaction efficiency is improved; in the ring-opening reaction, phenylhydrazine is reserved as a ring-opening reagent; a ring-opening product is subjected to ring closing again in a system without performing separation; and then the product after being subjected to ring closing is rectified and purified, and is subjected to ring opening in an acidic condition to obtain a target compound, so that residual amount of a toxic substance which refers to phenylhydrazine is greatly reduced.

Description

technical field [0001] The invention relates to the technical field of organic synthesis, in particular to a process for synthesizing dimethylcysteine ​​hydrochloride. Background technique [0002] Dimethylcysteine ​​hydrochloride is an important intermediate of vornimulin hydrochloride, which is a new generation of pleuromutilin semi-synthetic antibiotics, belonging to diterpenes, the same as tiamulin class of drugs, is an animal-specific antibiotics. It is mainly used for the prevention and treatment of mycoplasma disease and gram-positive bacterial infection in pigs, cattle, sheep and poultry. [0003] At present, there are literature reports on its preparation method, as follows: [0004] Patent CN102432510A discloses a kind of synthetic method of dimethyl cysteamine hydrochloride: [0005] (1), ring-closing reaction: Synthesize 5,5-dimethyl-2-isopropylthiazoline with isobutyraldehyde, elemental sulfur, ammonia and triethylamine as raw materials; [0006] (2), reduct...

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): C07C319/06C07C323/25
CPCC07C319/06C07D277/04C07D277/10C07D277/60C07D417/04C07C323/25
Inventor 吴红辉汤文杰沈小明樊彬
Owner 杭州扬帆化工科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com