Verfahren zur Herstellung von 2,6-Dichlor-5-fluornicotinonitril und die chemische Verbindung 3-Cyano-2-hydroxy-5-fluorpyrid-6-on-mononatriumsalz sowie dessen Tautomere

摘要

The invention relates to 2,6-dichloro-5-fluoronicotinitrile which can be advantageously obtained by reacting 3-cyano-2-hydroxy-5-fluoropyride-6-one and/or its tautomers and/or its salts and/or their tautomers with phosphorus trichloride and chloric gas in a solvent with addition of a basic catalyst at temperatures between 30 and 300 DEG C, and then by hydrolysis. The 3-cyano-2-hydroxy-5-fluoropyride-6-one-monosodium salt which can be used is a new chemical compound that is easy to obtain from 3-cyano-2-hydroxy-5-fluoropyride-6-one and/or its tautomers by reaction with alcoholate and precipitation with a moderately weak acid.