Sulfoximines are novel privileged scaffolds that have been applied as pharmaceuticals and bioactive compound as well as ligands and chiral auxiliaries in asymmetric syntheses. As a consequence, the development of efficient methods for the synthesis of sulfoximines and their functionalizations is greatly needed. However, despite the significant advances made in the functionalization of sulfoximines, only a few examples of 1,2-benothiazines, which are more attractive pharmacophores as a type of cyclic sulfoximine, have been reported. Herein, we have developed an efficient synthetic method for a wide range of 1,2-benzothiazines bearing pyridyl as well as carbonyl groups by a rhodium-catalyzed domino C−H activation/cyclizetion/elimination of alcohol process starting from S-aryl sulfoximine and pyridotriazole compounds.This work was supported by the Human Resource Training Program for Regional Innovation and Creativity through the Ministry of Education and National Research Foundation of Korea (NRF-2015H1C1A1035955)