COBALT(II) CATALYZED REACTION OF ALKENES WITH ALIPHATIC-ALDEHYDES AND MOLECULAR-OXYGEN - SCOPE AND MECHANISM

A variety of cobalt(II) complexes can be prepared using Schiff's bases derived from aromatic aldehydes and amines or alpha-aminoesters. These complexes are versatile catalyst for the reaction between aliphatic aldehydes and various alkenes- The outcome of the reaction is controlled by the electronic nature of the alkene as the electron deficient alkenes undergo oxidative addition of aldehydes followed by dioxygen incorporation to yield 2-hydroxy(acyloxy)-4-oxoesters or nitriles whereas unactivated or electron rich alkenes afford the corresponding epoxides. These reactions are proceeding via a radical pathway and a common acylcobalt intermediate is proposed for the formation of 4 as well as the epoxides 7.