Selective N-N or N-S bond cleavage of 1-trifluoromethyl benzotriazoles enables divergent synthesis of 1,2,4-benzotriazines and benzotriazoles

A variety of 1,2,4-benzotriazines and benzotriazoles are conveniently and divergently synthesized via novel metal-free cascade reactions of 1-trifluoromethyl benzotriazoles with alkyl bromides. The LiOH-mediated cascade reactions initiated by N-N bond cleavage smoothly afforded the 1,2,4-benzotriazine derivatives, and N1-alkylated benzotriazoles were selectively formed via Cs2CO3-mediated desulfonylative substitution based on N-S bond cleavage. A variety of 1,2,4-benzotriazines and benzotriazoles are conveniently and divergently synthesized via selective N-N or N-S bond cleavage of 1-trifluoromethyl benzotriazoles under different basic conditions.