Structures of Transition States in Metal-Mediated O_2-Activation Reactions

摘要

Enrichment of heavy oxygen (~(18)O) from its level at natural abundance is widely used to probe O_2-dependent processes in the atmospheric and biological sciences.Here we describe the first application of this technique to O_2-binding reactions of classic inorganic compounds.Competitive ~(18)O kinetic isotope effects (KIEs) reflecting the ratio of second-order rate constants for the formation of eta~2-peroxide compounds from ~(16,16)O_2 and ~(18,16)O_2 (k_(16,16)/k_(18,16)) have been determined (Scheme 1).