DISPLACEMENT OF NORBORNADIENE (NBD) FROM PtMe2(NBD) BY N-DONORS, DIMETHYLSULFOXIDE, AND CYANIDE, AND REACTIONS OF cis-PtMe2L2 WITH IODOMETHANE

Article abstract of DOI:10.1016/0022-328X(86)80119-X

Norbornadiene (NBD) was displaced from PtMe2(NBD) by a range of ligands L to form cis-PtMe2L2 (L = pyridine (py), NH3 dimethylsulfoxide (DMSO); L₂ = 2,2'-bipyridyl (bipy), ethylenediamine (en), N,N,N',N'-tetramethylethylenediamine (tmen) - but not L = acetonitrile, benzonitrile, N,N-dimethylformamide, or water).These reactions occur more readily than the corresponding displacements of 1,5-cyclooctadiene (COD) from PtMe2(COD).Cyanide readily displaced the diolefin from either PtMe2(NBD) or PtMe2(COD) to form cis-PtMe2(CN)2^2-, but no reaction occurred with bromide, chloride, and acetylacetonate.Thiocyanate and iodide slowly reacted, but no methyl-platinum product was obtained.The reaction of each of the compounds PtMe2L2 with MeI was studied in benzene.PtMe2(NBD) gave 4.With L = py, 1/2(bipy), or 1/2(tmen), PtMe3IL2 was obtained rapidly at room temperature.For the sparingly soluble compounds with L = NH3 or 1/2(en), heating was necessary for reaction.The product from PtMe2(en) was PtMe3I(en), but cis-PtMe2(NH3)2 gave a mixture of I.With L = DMSO, heating initially gave PtMe3I(DMSO)2, which slowly lost DMSO to form 4.For L = py, 1/2(tmen), treatment with acid readily removed L from PtMe3IL2.