Counter-Current chromatography separation of isatin derivatives using the sandmeyer methodology

A rapid and efficient method, using high-speed counter-current chromatography (HSCCC) technique, was developed for the separation of isomeric isatin derivatives, prepared following the Sandmeyer route. The biphasic solvent system composed of hexane: ethyl acetate: ethanol: water 1:0.5:0.5:1 (v/v/v/v) was used for all separations.