Organoplatinum(IV) compounds. II: Preparation and characterization of trimethylplatinum(IV) compounds with chelating nitrogen donor ligands. The crystal and molecular structure of iodotrimethyl[bis(3,5-dimethyl-1-pyrazolyl)methane]platinum(IV)

Abstract Compounds of the types Me 3 PtX(NN) (where X = Cl, I, OAc, NO 3 ; NN = bis(1-pyrazolyl)methane (pz 2 CH 2 ), bis(3,5-dimethyl-1-pyrazolyl)methane ((Me 2 pz) 2 CH 2 ), or bis(2-pyridyl)methane (py 2 CH 2 )), [Me 3 Pt(NNN)][PF 6 ] (where NNN=tris(1-pyrazolyl)methane (pz 3 CH), or tris(2-pyridyl)methane (py 3 CH)), and [Me 3 Pt((Me 2 pz) 2 CH 2 (py)][PF 6 ] have been prepared and characterized by elemental analyses and 1 H and 13 C NMR spectroscopy; the structure of Me 6 PtI[(Me 2 pz) 2 CH 2 ] ( 1 ) has also been determined by X-ray crystallography. Crystals of 1 are orthorhombic, space group Pcmn with four molecules in a unit cell of dimensions a 11.936(5), b 14.462(4), c 10.138(5) A. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations to R = 0.022 for 1719 observed data. The molecule has crystallographic mirror symmetry. The Pt atom has octahedral geometry with one methyl group trans to iodine and two methyl groups trans to the N atoms of the bidentate ligand (PtI 2.843(1), PtN, 2.236(4), PtC 2.077(6) ( trans to I) and 2.032(5) A ( trans to N)).