Inorganic Chemistry, Vol.58, No.11, 7584-7592, 2019
Directed Hydroxylation of sp(2) and sp(3) C-H Bonds Using Stoichiometric Amounts of Cu and H2O2
The use of copper for C-H bond functionalization, compared to other metals, is relatively unexplored. Herein, we report a synthetic protocol for the regioselective hydroxylation of sp(2) and sp(3) C-H bonds using a directing group, stoichiometric amounts of Cu and H2O2. A wide array of aromatic ketones and aldehydes are oxidized in the carbonyl gamma-position with remarkable yields. We also expanded this methodology to hydroxylate the beta-position of alkylic ketones. Spectroscopic characterization, kinetics, and density functional theory calculations point toward the involvement of a mononuclear LCuII(OOH) species, which oxidizes the aromatic sp(2) C-H bonds via a concerted heterolytic O-O bond cleavage with concomitant electrophilic attack on the arene system.