Transition-Metal-Free C–H Hydroxylation of Carbonyl Compounds

Transition metal
and reductant free α-C­(sp3)–H hydroxylation
of carbonyl compounds are reported. This method is promoted by commercially
available inexpensive KO-t-Bu and atmospheric air
as an oxidant at room temperature. This unified strategy is also very
facile for hydroxylation of various carbonyl compound derivatives
to obtain quaternary hydroxyl compounds in excellent yield. A preliminary
mechanistic investigation, supported by isotope labeling and computational
studies, suggests the formation of a peroxide bond and its cleavage
by in situ generated enolate.