Synthesis of 17H-tetrabenzo[a,c,g,i]fluorene derivatives as chiral selectors for enantiomeric separation by HPLC on porous graphitised carbon
Abstract
The synthesis of the amides 2 which are designed to be selectors containing the chiral N-(3,5-dinitrobenzoyl)-α-phenylglycine covalently linked to tetrabenzo[a,c,g,i]fluorene is described. These amides are strongly adsorbed onto porous graphitised carbon, which affords chiral stationary phases that are able to resolve both racemic aromatic alcohols 3 and the methyl esters of Fmoc amino acids 4 on microgram quantities using high-pressure liquid chromatography. Two methods of preparation of these chiral phases from 2 and porous graphitised carbon are described and the stability of these phases to the chromatographic conditions and to water have also been investigated.