Free Radical Chemistry has a comparatively long history. Before the accep- tance of the quadrivalence of carbon, various attempts were made to prepare trivalent carbon species like methyl and ethyl. Initial investigations involving reaction between alkyl iodides and zinc were thought to be successful but were subsequently branded as failures 2. In fact free methyl and ethyl were transient radicals involved in the reactions, but because of their short lifetimes the radicals were not detected, and only the hydrocarbons formed by dimeri- th sation of the radicals were isolated. At the beginning...