The Ru(II)-catalyzed imidation of the o-C-H bond in arenes with N-tosyloxyphthalimide is realized with the assistance of a methyl phenylsulfoximine (MPS) directing group. This method is applicable to access the hitherto difficult o-C-H di-imidation products. The sequential C-N and C-C bond formation of o-C-H arenes creates peripherally decorated benzoic acid derivatives. The readily removable MPS-DG and easily modifiable phthaloyl moiety make this strategy synthetically viable for constructing highly functionalized C-N bearing arenes and heteroarenes.