Ricerc@Sapienza

The here proposed project aims, in its first stage, to investigate new fields of application of the not too exploited, although extremely powerful, branch of chromatography, known by the term `Dynamic Chromatography¿ (DC), currently adopted exclusively for the purpose of studying kinetic aspects characterizing both steric and constitutional isomerization of organic molecules, typically promoted by acid or basic conditions. More in particular, to date, such a typology of isomerizations have always been analyzed performing DC determinations with the on-column process evolving in equilibrium condition. Thus, one of the pursued goals will be that to promote more generic on-column organic reactions, far from their condition of equilibrium, and to analyze the so resulting nonclassic dynamic chromatograms by suitable profile-simulation, which will allow to achieve the kinetic quantities of the investigated reactions. As a variant of this approach, it is also planned to bound on the silica of a HPLC column one of the reacting species, selected with condition to be easily restored to its initial state by suitable chemical treatment at the end of the analyzed reaction. In this way, the so modified HPLC column will be able to act as a reactor towards suitable injected species. More classic derivatization of silica with organic catalysts will also be carried out with the intent to prepare original flow-reactors. Finally, classical DC determinations and theoretical calculations are also planned to be performed in aim to assess the free energy activation barriers, deltaG#, which oppose the enantiomerization of tricyclic molecules endowed with planar chirality, commonly employed as drugs in racemate version. In this way, will be possible to select the species characterized by low deltaG# barriers, and design for these not too extensive chemical modifications, able to strongly increase the deltaG# values and, therefore, make possible their existence as single stable enantiomers.