Preparation of 2-Cl-5-F-nicotinate and nicotonic acid
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- 上海药明康德新药开发有限公司
- Publication Date
- 2007-12-19
- Estimated Expiration
- Not applicable · inactive patent
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Abstract
Description
Technical field:
[0001] The invention relates to a preparation method of nicotinic acid ester with chlorine and fluorine groups and nicotinic acid drug intermediates, in particular to a preparation method of 2-chloro-5-fluoro-nicotinic acid ester and acid. Background technique:
[0002] 2-Chloro-5-fluoro-nicotinic acid ester and 2-chloro-5-fluoro-nicotinic acid are relatively important drug intermediates, but so far there is no effective synthetic method to prepare this product, and it has been reported in the literature Two preparation methods, one method is to use 2,6-dichloro-5-fluoro-nicotinic acid ethyl ester to react with methyl mercaptan first, and then use Raney nickel as a catalyst to hydrogenate and remove methyl mercapto to obtain 2-chloro- 5-Fluoro-nicotinic acid ethyl ester, and then hydrolyzed to obtain 2-chloro-5-fluoro-nicotinic acid (J.Med.Chem.1993.2678-2688); another method is to start from 2-hydroxy-nicotinic acid and first nitrate Then chlorinated to gi...