Selective Aromatic C-H Hydroxylation Enabled by η(6)-Coordination to Iridium(III)

We report an aromatic C-H hydroxylation protocol in which the arene is activated through η(6)-coordination to an iridium(III) complex. η(6)-Coordination of the arene increases its electrophilicity and allows for high positional selectivity of hydroxylation at the site of least electron density. Through investigation of intermediate η(5)-cyclohexadienyl adducts and arene exchange reactions, we evaluate incorporation of arene π-activation into a catalytic cycle for C-H functionalization.