title: Novel pyrimidine-bridged platinum(II) complexes: multinuclear magnetic resonance spectroscopy and crystal structures of (NR4)2[(PtCl3)2(mu-pyrimidine)] and cis- and trans-[Pt(R2SO)Cl2]2(mu-pyrimidine).
abstract: Two new types of pyrimidine-bridged Pt(II) complexes, (NR4)2[(PtCl3)2(mu-pm)] and cis- and trans-[Pt(R2SO)Cl2]2(mu-pm) where pm = pyrimidine, were synthesized and characterized by IR and multinuclear magnetic resonance spectroscopies and by crystallographic methods. Compounds with dimethylsulfoxide, tetramethylenesulfoxide, di-n-propylsulfoxide (DPrSO), di-n-butylsulfoxide (DBuSO), dibenzylsulfoxide (DBzSO), and diphenylsulfoxide were studied. The aqueous reaction of K2PtCl4 with pyrimidine produced the [(PtCl3)2(mu-pm)](2-) ions, which can be precipitated with a NR4(+) salt. The aqueous reaction of K[Pt(R2SO)Cl3] with pyrimidine in a 2:1 ratio produced the dinuclear species trans-[Pt(R2SO)Cl2]2(mu-pm). With DBuSO and DBzSO, the analogous cis isomers were also obtained. The 195Pt NMR resonances of the trans dimeric complexes were observed at higher field (av -3088 ppm) than the cis compounds (av -2948 ppm). The 195Pt coupling constants with the atoms of pyrimidine 3J(195Pt-1H) and 3J(195Pt-13C) are larger in the cis configuration than in the trans analogues. The crystal structures of two ionic complexes, (NR4)2[(PtCl3)2(mu-pm)] (R = Me and n-Bu), and of three mixed-ligands dimers, trans-[Pt(R2SO)Cl2]2(mu-pm) (R2SO = DMSO, DPrSO) and cis-Pt(DBuSO)Cl2]2(mu-pm), were determined.
authors.affiliation: Département de Chimie, Université du Québec à Montréal, C. P. 8888, Succ. Centre-ville, Montréal, H3C 3P8, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Nédélec
authors.forename: F D
authors.initials: FD
authors.lastname: Rochon
mesh_terms: D002247:Carbon Isotopes; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009944:Organoplatinum Compounds / Q000737:chemistry*; D011522:Protons; D011743:Pyrimidines / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
chemical_list: D002247:Carbon Isotopes; D009944:Organoplatinum Compounds; D011522:Protons; D011743:Pyrimidines