Palladium-Catalyzed Divergent Regioselective Homocoupling and Hydroxylation of 3-Arylbenzo[d]isoxazoles

Palladium-catalyzed oxidative homocoupling and hydroxylation of 3-arylbenzo[d]isoxazoles have been developed via direct C(sp²)−H bond activation using benzoisoxazoles as a new directing group. The protocols offer a divergent approach to functionalized, synthetically useful benzoisoxazoles in good yields. Critically, 1-iodo-4-methoxybenzene functions as an oxidant to mediate the dehydrogenative homocoupling and minimize the cross-coupling. A dual-core dimeric palladacycle intermediate is confirmed by X-ray crystallography, and serves as an active catalytic species in the catalytic cycles. (Figure presented.).