Ultra-fast microscale purification of chiral racemates and achiral pharmaceuticals with analytical supercritical fluid chromatography

Improving efficiency while maintaining high quality separations is a central theme for specialized analytical/purification groups supporting discovery chemistry programs. Supercritical fluid chromatography (SFC) has become the prevalent technique for chiral separation and a complementary technique to reverse phase high-pressure liquid chromatography (RP-HPLC). In this manuscript we demonstrate the successful micro-isolation of chiral racemates, small molecules, and peptides using a sub-minute method on an analytical SFC system. The addition of a custom gas liquid separator (GLS) and alterations to the fluidic pathways allow the fractionation of desired products on a micro-scale SFC platform, providing analytical method development, purifications, and purity confirmation on a single SFC system. This enables micro-purification of pharmaceuticals including chiral racemates at high speed and reduced cost of materials. The resulting small-quantity, high-purity products enable follow-up enantioselective isolations from racemic products of parallel synthesis libraries. The processes established here will be beneficial for the isolations of other desired products in complex crude mixtures.