“…During our mechanism-based screen of one hundred potential substrates for photocatalysis, we discovered benzotriazoles as anew quencher class.Aided by data obtained, we designed and realized an ovel photocatalytic hydro-denitrogenation reaction of various 1-(benzoyl)benzotriazoles (1)l eading to N-arylbenzamides (see Scheme 1). [2] While benzotriazoles have demonstrated activity under irradiation with ultraviolet light such as in the photolytic Graebe-Ullmann carbazole synthesis, [5] functionalization of these compounds by visible-light photocatalysis has,t ot he best of our knowledge,n ot been reported before. Herein, building on the discovery of this new quencher class, we greatly expand the scope of visible-light photocatalysis with benzotriazoles by developing three new o-functionalization reactions.D enitrogenative routes to o-borylated, -thiolated, and -alkylated N-arylbenzamide derivatives directly from bench-stable substrates have been developed by anovel disconnection strategy for the synthesis of these common organic building blocks (Scheme 1).Firstly,w et urned to the results of the mechanism-based screening study to obtain information on the operating quenching mode and to identify the optimum photocatalyst and substrate combination.…”