STRUCTURAL STUDIES OF UNUSUALLY DISORDERED DIORGANOPLATINUM(IV) COMPLEXES CONTAINING THE CATIONS [PTIR2(L-N,N',N'')]+, WHERE THE LIGANDS-L ARE FACIALLY COORDINATED

The reaction of [PtPh2(SEt2)]2 with tris(pyrazol-1-yl)methane [(pz)3CH] and iodine in dichloromethane gives the platinum(IV) complex [PtIPh2{(pz)3CH-N,N′,N″}]2[I][I3] (1). Complex 1, and related complexes of the facially coordinated tridentate ligands (pz)2(mim)CH (mim = N-methylimidazol-2-yl) and (pz)2(py)CH (py = pyridin-2-yl) have octahedral geometry for platinum(IV), "ptIC2N3", and exhibit unusual disorder in the solid state. Complex 1 has two cations in the asymmetric unit, with one cation well ordered and the other showing disorder between the coordinated iodide and one phenyl group position. The complexes [PtIMe2{(pz)2(mim)CH- N,N′,N″}]I (2a) and [PtIMe2{(pz)2(py)CH-N,N′,N″)}]I (2b) have coordinated iodide disordered with both methyl groups; in 2a iodine is predominantly trans to the pz groups, and in 2b iodine is predominantly trans to the py group. © 1992.<p></p>