AN IMPROVED PROCESS FOR THE REMOVAL OF PALLADIUM FROM 4-AMINO-3-HALO-5-FLUORO-6-(ARYL) PYRIDINE-2-CARBOXYLATES AND 4-AMINO-3-HALO-6-(ARYL)PYRIDINE-2-CARBOXYLATES

摘要

Residual palladium is removed and recovered from 4-amino-3-halo-5-fluoro-6-(aryl)pyridine-2-carboxylates and 4-amino-3-halo-6-(aryl)pyridine-2-carboxylates by treatment with an aqueous solution containing from about 20 to about 50% of an alkali metal bisulfite at a temperature from about 60 to about 90 °C and a pH from about 2.0 to about 8.0.