Platinum(II) Complexes with Tetradentate Dianionic (O∧C*∧C*∧O)-Ligands

New tetradentate (OC)-C-boolean AND*C-boolean AND*O-boolean AND-ligands and the corresponding biscarbene platinum(II) complexes are reported. They were fully characterized by H-1 NMR and C-13 NMR spectroscopy as well as elemental analysis. Additionally, solid-state structures of bis [3,3'-(2-hydroxyethyl)-1H-imidazolium-2,2'-diylidene] methane-1, 1'-diylplatinum(II) dibromide and of bis [3,3'-(2-ethoxide)-1H-imidazolium-2,2'-diylidene]methane-1,1'-diylplatinum(II) potassium bromide are reported. The latter can be characterized as a one-dimensional chain structure formed by coordination of potassium bromide.