Naphthalene Hydrodearomatization\nvia Controllable\nPhotocatalytic Hydroboration

The\nphotocatalytic dearomative 1,4-hydroboration of naphthalenes\nwith an N-heterocyclic carbene borane (NHC-BH<sub>3</sub>) complex\nwas reported herein with controllable regioselectivity and chemoselectivity.\nThis protocol yielded a wide range of naphthalene derivatives bearing\nvarious functional groups, notably bioactive compounds. Hydroboration\noccurred through the cooperation of photoredox and hydrogen atom transfer\nvia boryl radical addition to naphthalene and further selective protonation.\nNotably, tuning the conditions could lead to further hydrogenation\nof the tetrahydroboration products. Mechanistic studies, including\nexperimental and computational studies, elucidated the mechanism for\nthe regioselectivity.