Control of Product Distribution and Mechanism by Ligation and Electric Field in the Thermal Activation of Methane

An unexpected mechanistic switch as well as a change of the product distribution in the thermal gas‐phase activation of methane have been identified when diatomic [ZnO] .+ is ligated with acetonitrile. Theoretical studies suggest that a strong metal–carbon attraction in the pristine [ZnO] .+ species plays an important role in the rebound of the incipient CH 3 . radical to the metal center, thus permitting the competitive generation of CH 3 . , OH . , and CH 3 OH. This interaction is drastically weakened by a single CH 3 CN ligand. As a result, upon ligation the proton‐coupled single electron transfer that prevails for [ZnO] .+ /CH 4 switches to the classical hydrogen‐atom‐transfer process, thus giving rise to the exclusive expulsion of CH 3 . . This ligand effect can be modeled quite well by an oriented external electric field of a negative point charge.