Herein, we provide two nickel complexes and a series of control experiments to study the mechanism of the nickel-catalyzed transannulation reaction of 1,2,3,4-benzo-thiatriazin-1,1(2H)-dioxide with aryne and alkyne in detail. In addition, we provide a new protocol for the cycloaddition of 1,2,3,4-benzothiatriazin-1,1(2H)-dioxide with alkyne on the basis of a similar reaction pathway.
