ALLYLATION AND OXIDATION REACTIONS PROMOTED BY COBALT(ll) COMPLEXES.

Article abstract of DOI:10.1016/S0040-4020(01)97186-8

Two examples of radical reactions involving cobalt complexes are described.The first one concerns the reactions of allylcobaloximes with 2-bromo 2-phenylacetonitriles leading to the corresponding monoallyl derivatives.It is shown that both the rate and regioselectivity of the reactions are affected by the nature of the substituents on the phenyl group : electron-withdrawing groups give higher rates and highly regiospecific reactions.The second type of radical reactions wich finds useful synthetic applications is the oxidation of phenols by O2 catalysed by Schiff base cobalt complexes.By choosing carefully the catalyst and the solvent, these oxidations can be highly selective, quinones being the major oxidation products in most cases.