Homogeneous Palladium(1I) Mediated Oxidation of Methane SELECTIVE FUNCTIONALISATION UNDER MILD CONDITIONS

A metal catalysed, electrophilic approach to methane oxidation is discussed. This involves the oxidation of methane to the corresponding methyl ester in trijluomacetic acid; the oxidant is hydrogen peroxide and the catalyst is the palladiumflz) ion. The latter species activates methane by the electrophilic cleavage of a C-H bond, and then acts as a two-electron oxidant towards the resultant metal-bound methyl group. The hydrogen peroxide reoxidises palladium(0) back to palladium(ll). Methane is the most abundant and the least reactive member of the hydrocarbon family. Thus, the selective functionalisation, preferably catalytic, of methane under mild conditions is one of the most challenging chemical problems, in addition to being of great practical importance. Among the various functionalisation possibilities, oxidative func