Method for preparing 3-bromo-5-chloro-1,8-naphthyridine
A kind of naphthalene and reaction technology, applied in the field of preparation of important pharmaceutical intermediates
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0020] (1) Synthesis of 6-bromo-1,8-naphthyridine-2,4-diol
[0021] 30g of 5-bromo-2-aminopyridine and 24ml of diethyl malonate were added to 160ml of tetrahydrofuran, stirred, heated, refluxed for 4 hours, cooled, concentrated under reduced pressure, and the residue was separated by chromatography to obtain 37g of product.
[0022] (2) Synthesis of 6-bromo-2,4-dichloro-1,8-naphthyridine
[0023] Dissolve 35g of the product obtained in the first step in 200ml of phosphorus oxychloride, heat to reflux, and react for 12 hours, pour the reaction solution into ice water, extract with ethyl acetate, wash the organic phase three times with saturated saline, and then wash with anhydrous sulfuric acid It was dried over sodium, concentrated under reduced pressure, and the residue was separated by column chromatography to obtain 18 g of the product as an oil.
[0024] (3) Synthesis of 3-bromo-5-chloro-1,8-naphthyridine
[0025] Add 15g of 6-bromo-2,4-dichloro-1,8-naphthyridine to 200m...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 


