Cyclometalated\nC^C* Platinum(IV) NHC Complexes

We present a previously unknown\nseries of cyclometalated platinum(IV)\nNHC complexes, obtained by oxidative addition of iodine, iodomethane,\nand different benzyl bromides to platinum(II) complexes with cyclometalated\nC^C* dibenzofuran, dibenzothiophene, and phenylimidazole ligands together\nwith an acetylacetonate ligand. All compounds were characterized by\nstandard techniques (<sup>1</sup>H, <sup>13</sup>C, and <sup>195</sup>Pt NMR and elemental analysis), and for three complexes, solid-state\nstructures could be obtained. DFT calculations (B3LYP(d3)/def2-TZVPP\nincluding dispersion interactions in dichloromethane and acetone)\nwere performed to investigate the mechanism of the oxidation and explain\nthe exclusive formation of the observed <i>trans</i> products.