Selective oxidation/oxygenation of organic molecules is important in chemistry and biology, and is of substantial commercial significance. A wide variety of metalloenzymes are known to catalyze such reactions under very mild conditions with high regio- and stereoselectivity. Metalloenzymes employ diverse arrays of reaction centers, including heme, nonheme iron, mono-, di-, and multinuclear copper sites, and heteronuclear transition metal systems, to activate molecular oxygen and accomplish selective oxidation reactions. A variety of active-oxygen metal species with the O-O bond either broken or intact are possible reactive intermediates responsible for the substrate oxidation/oxygenation. Identifying these species and elucidating the mechanism(s) by which they perform selective oxidations is an important research goal that continues to stimulate extensive experimental and theoretical efforts, including the development of synthetic bio-inspired catalysts. Similar efforts are underway in research aimed at understanding nonbiomimetic catalytic oxidations. These systems operate by different pathways involving direct reactions of organic substrates with heavier transition metals. The objective of this symposium is to discuss recent developments in the research areas of dioxygen activation chemistry and catalytic oxidation reactions by bringing together researchers who study metalloproteins, bio-inspired model complexes, and/or heavy metal catalysts. |
