Continued Progress Towards Efficient Functionalization of Natural and Non Natural Targets Under Mild Conditions. Oxygenation via C-H Bond Activation with Dioxiranes

The successful isolation and characterization of a dioxirane species in the 1988 opened up a one of the most attractive methods for the efficient oxidation of simple and/or structurally complex molecules. Dioxiranes today rank among the most powerful tools in organic chemistry, with numerous applications in commercially important processes. These are quickly and remarkably recognized as efficient oxygen transfer agents, especially for epoxidations and for a wide range of O-insertion into C-H bonds. Dioxiranes also appear as highly selective (chemo-, regio- and stereo-) oxidants, despite their reactivity under mild and strictly neutral conditions controlled by a combination of steric and electronic factors and possess catalytic activity. In this review, we discuss some of the most recent and significant developments in the selective homogeneous and heterogeneous oxyfunctionalization of non-activated C-H bonds in hydrocarbons of natural and non-natural targets using isolated dioxiranes or more generally, using the ketones (i.e., the dioxirane precursors) as organocatalysts.