An unusual fact of C-C reductive elimination reaction in bis-chelated Pt(IV) complexes under mild conditions was studied. It has been shown that breaking at least one of the chelate rings is required to promote a carbon-carbon bond formation reaction. An intermediate complex, which resulted from a chelate ligand breaking process, was detected directly in the reaction mixture using 2D 1H–195Pt heteronuclear NMR spectroscopy.