Indexed on: 25 Jan '17Published on: 24 Jan '17Published in: Advanced Synthesis & Catalysis
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.