Preparation method of doxycycline intermediate 11[alpha]-chloromethene oxytetracycline
The technology of chloromethicillin and chlorooxytetracycline is applied in the field of preparation of doxycycline intermediate 11α-chloromethicillin, which can solve the trouble of molecular sieve activation, the inability of molecular sieve to effectively activate and produce The process is cumbersome and other problems, to achieve the effect of reducing potential safety hazards, reducing environmental pressure, and high dehydration yield
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0027] The preparation method of 11α-chloromethoxytetracycline
[0028] Add 105.11g of dichloromethane into a 250ml reaction bottle equipped with a thermometer and mechanical stirring, cool the reaction bottle to -26°C, add 30.01g of 11α-oxytetracycline chloride, stir and disperse, and pour into Put 15.52 g of 1,1-dichloromethyl-N,N-dimethylamine into the reaction flask, keep warm at -20°C to -10°C and stir for 10 hours, and absorb the tail gas of feeding and reaction process with two-stage liquid caustic soda. After the reaction was completed, the detection conversion rate was 90.5%, and the selectivity was 97.6%. The yield is then 88.3%.
[0029] Wherein dehydrating agent (1,1-dichloromethyl-N,N-dimethylamine) preparation
[0030] Add 300.05g of dichloromethane and 100.02g of thionyl chloride into a 500ml reaction flask equipped with a thermometer and mechanical stirring, start stirring, cool the reaction flask to 3°C, and drop it into the reaction flask when it is sealed ...
Embodiment 2
[0032] The preparation method of 11α-chloromethoxytetracycline
[0033] Add 104.91g of dichloromethane into a 250ml reaction bottle equipped with a thermometer and mechanical stirring, cool the reaction bottle to -24°C, add 30.04g of 11α-oxytetracycline chloride, stir and disperse, and pour into 15.49 g of 1,1-dichloromethyl-N,N-dimethylamine (preparation method is the same as that in Example 1) was put into the reaction flask, kept at -20°C to -10°C and stirred for 13 hours. Feeding and reaction process tail gas is absorbed by two-stage liquid caustic soda. After the reaction was completed, the detection conversion rate was 93.5%, and the selectivity was 97.1%. The yield is then 90.8%.
Embodiment 3
[0035] The preparation method of 11α-chloromethoxytetracycline
[0036] Add 105.12 g of dichloromethane into a 250 ml reaction bottle equipped with a thermometer and mechanical stirring, cool the reaction bottle to -27°C, add 30.06 g of 11α-oxytetracycline chloride, stir and disperse, and pour into Put 23.29 g of 1,1-dichloromethyl-N,N-dimethylamine (the preparation method is the same as in Example 1) into the reaction bottle, keep warm at -20°C to -10°C and stir for 13 hours. Feeding and reaction process tail gas is absorbed by two-stage liquid caustic soda. After the reaction is finished, the detection conversion rate is 98.8%, the selectivity is 97.0%, and the yield is 95.8%.
PUM
Abstract
Description
Claims
Application Information
- R&D Engineer
- R&D Manager
- IP Professional
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
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