2,5-Diketopiperazine Catalysts as Activators of Dioxygen in Oxidative Processes
Marina Petsi, Alexandros L. Zografos
Abstract
The ability of natural and non-natural dipeptides to act as activators of dioxygen in the absence of metallic cocatalysts is reported here. Proline-derived 2,5-diketopiperazines were found active as catalytic mediators for various chemoselective aerobic oxidation processes including the oxidation of sulfides to sulfoxides, the epoxidation of alkenes, and the oxidative coupling of phenols. Mechanistic studies and intercepted intermediates evidence the existence of catalytically active hydroperoxide species that work in unison in a catalytic cycle that resembles the mechanism of flavin-containing monooxygenases.
Topics & Concepts
DiketopiperazinesChemistryCatalysisCatalytic cycleMonooxygenaseOxidative coupling of methaneOxidative phosphorylationFlavin groupCombinatorial chemistryStereochemistryPhotochemistryOrganic chemistryEnzymeBiochemistryCytochrome P450Oxidative Organic Chemistry ReactionsSynthesis and Catalytic ReactionsRadical Photochemical Reactions