Boron-Mediated C1-Hydroxylation of Carbazoles Using Benzoyl as the Traceless Directing Group

Herein, a metal-free BBr₃-mediated C-H hydroxylation of carbazoles using benzoyl as a traceless directing group has been reported. This protocol features high efficiency and operational simplicity, offering the valuable 1-hydroxycarbazoles in moderate to excellent yields with scale-up ability under mild conditions. In addition, this transformation can be performed in one-pot, which is highlighted by the utility for the total synthesis of carbazole alkaloid murrayaquinone A.