Mechanistic aspects of gas-phase hydrogen-atom transfer from methane to [CO]·+ and [SiO]·+: Why do they differ?

Abstract

The reactivity of the two diatomic congeneric systems [CO] ·+ and [SiO]·+ towards methane has been investigated by means of mass spectrometry and quantum-chemical calculations. While [CO]·+ gives rise to three different reaction channels, [SiO]·+ reacts only by hydrogen-atom transfer (HAT) from methane under thermal conditions. A theoretical analysis of the respective HAT processes reveals two distinctly different mechanistic pathways for [CO] ·+ and [SiO]·+, and a comparison to the higher metal oxides of Group 14 emphasizes the particular role of carbon as a second-row p element. Under investigation! The reactivity of the two diatomic systems [CO]·+ and [SiO]·+ towards methane has been investigated by means of mass spectrometry and quantum-chemical calculations. An experimental and theoretical analysis of the respective hydrogen-atom transfer (HAT) processes reveals two distinctly different mechanistic pathways for [CO]·+ and [SiO]·+, further emphasizing the particular role of carbon as a second-row p element. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.