Naphthalene Hydrodearomatization via Controllable Photocatalytic Hydroboration
Wengang Xu1, Juan Tao1, Yu-Qi Wang2
1College of New Energy, State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, P. R. China.
Abstract:
The photocatalytic dearomative 1,4-hydroboration of naphthalenes with an N-heterocyclic carbene borane (NHC-BH3) complex was reported herein with controllable regioselectivity and chemoselectivity. This protocol yielded a wide range of naphthalene derivatives bearing various functional groups, notably bioactive compounds. Hydroboration occurred through the cooperation of photoredox and hydrogen atom transfer via boryl radical addition to naphthalene and further selective protonation. Notably, tuning the conditions could lead to further hydrogenation of the tetrahydroboration products. Mechanistic studies, including experimental and computational studies, elucidated the mechanism for the regioselectivity.
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