4-chloropyridine-2,5-dicarboxylic acid synthesis

Yield:-

Reaction Conditions:

with potassium permanganate in water; for 24 h;Reflux;

Steps:

1.a.2

Step 2: A mixture of 4-chloro-6-methyl-3-pyridinecarboxylic acid (10 g, 58.4mmol) and KMnO₄ (27.7 g, 175.4 mmol) in H₂O was reflux with stirring for 24 h. The mixture was cooled to temperature and filtrated. EtOH was added to the filtrate and filtrated again. The filtrate was concentrated by vacuo to give the crude product 17 g which was used directly to the next reaction without further purification.

References:

WO2010/59552,2010,A1 Location in patent:Page/Page column 13-14