Abstract: The oxidative addition of methyl iodide or molecular iodine to the bis(С,N-chelate) deprotonated diaminocarbene platinum(II) complexes [Pt{C(N(H)Ar)(NC(N(H)Ph)N(Ph)}2] (Ar = C6H3-2,6-Me2 (Xyl), C6H2-2,4,6-Me3 (Mes), and C6H4-4-Me (pTol)) affords the corresponding platinum(IV) derivatives in a yield of 89–99%. The addition of CF3CO2H is accompanied by the protonation of the nitrogen atoms of the diaminocarbene fragment to form the cationic complexes [PtI(X)-{C(N(H)Ar)(NC-(N(H)Ph)N(Ph)}2]CF3CO2H (X = Me, I). The structures of the compounds are determined by elemental analysis; high resolution mass spectrometry with electrospray ionization (ESI HRMS); IR spectroscopy; 1H, 13C{1H}, 19F{1H}, and 195Pt{1H} NMR spectroscopy; 2D NMR spectroscopy (1H,1Н COSY, 1H,1Н NOESY, 1H,13C HSQC, 1H,13C HMBC, 1H,15N HSQC, 1H,15N HMBC), and X-ray diffraction (XRD) and thermogravimetric analyses. The synthesized platinum(IV) complexes are thermally stable to 200–260°C and are electroneutral molecules with the octahedral coordination sphere formed by two deprotonated diaminocarbene C,N‑chelate substituents and iodine and methyl or two iodine atoms localized in the apical positions.