SYNTHESIS OF 3-HydroxyCinchoninic acid

The synthesis of the 3-hydroxycinchoninic acid has been performed with the reaction a commercially available isatin in presence of chloropyruvic acid (previously synthesized from pyruvic acid and sulfuryl chloride in 95-98% Yield.) in a aqueous potassium hydroxyde solution. After the workup the 3-hydroxycinchoninic acid is isolated as a yellow solid(60-71%).

For more information:

Organic Syntheses, Coll. Vol. 5, p.635 (1973); Vol. 40, p.54 (1960).

James Cason and James D. Willett.