Free Radicals in Synthesis and Biology

Free-radical reactions have been for long time the domain of the physical chemists and the basic chemical industry (polymerization of vinyl monomers, oxidation by molecular oxygen, chlorination of methane etc.), where the use of simple molecules and the possibility of partial conversions without heavy problems of product separations makes less dramatic the aspects of regio and chemoselectivity. As synonym of unselectivity, free radical reactions were considered of poor use in the synthesis of fine chemicals or sophisticated molecules, where a high selectivity is an essential condition for the success, or in the involvement of biological processes. Within the last 15 years, however, an authentic explosion of synthetic applications of free radical reactions occurred; they have gained a remarkable position among the selective methods of synthesis. At the same time the great importance of free radical reactions in fundamental biological processes and in the metabolism of drugs has been recognized. Thus a specialized meeting on these topics was generally felt appropriate. I had the honour and the onus to organize this workshop because for more than 30 years I have been involved in the research of free radical reactions. Thanks to a generous grant from NATO Scientific Affairs Division and the financial support of CNR and chemical industry (Montedison, Enichem, Zambon) such a meeting among almost 50 specialists and 15 observers of sufficient standard to take advantage of the discussion, became possible at Bardolino (Italy).