Abstract                                                                                                                                                                                                                                                                                                            The synthesis of new linear monoazaphenothiazine and its substituted derivatives via nickel catalyzed amidation reaction is reported. This was achieved by the condensation of 2-aminothiophenol and 2,3,5-trichloropyridine in aqueous basic medium to produce a new heterocyclic ring, 3-chloro-1-azaphenothiazine. Upon applying, Buchwald–Hartwig Cross coupling reaction, it leads to the syntheses of an array of new 3-amido derivatives which were obtained in good yields. The structures of the synthesized compounds were established based on their analytical and spectra data.