Chiral Imprinting in Molten Gallium Microspheres

Vijay Bhooshan Kumar, Dept of Chemistry, Bar-Ilan University, Ramat Gan, Israel

Chiral imprinting in gallium micro-particles can be attained by ultrasonic irradiation of molten gallium overlayered by an aqueous solution of a chiral compound. Such particles were prepared in solution of D- or L- tryptophan and separated by centrifugation. The particles were then immersed in pure water for leaching of the specific enantiomer, leaving molecular templates on the surface. Immersion of these particles in a racemic solution of tryptophan induced an enantiomeric excess of 6-12% by entrapment of the specific enantiomer from the solution. The extent of the enantiomeric excess was determined by polarimetry and circular dichroism measurements.