Oxidative addition chemistry of dimethyl(dipyridyl ketone)platinum(II)

Abstract

The dimethylplatinum(II) complex [PtMe2(DPK)] (DPK = di-2-pyridyl ketone) undergoes easy oxidative addition to give platinum(IV) complexes. For example, reaction of [PtMe2(DPK)] with MeI gave [PtIMe3(DPK)], reaction with N-chlorosuccinimide in methanol gave [PtCl(OMe)Me2(DPK)], and reaction with [FN(CH2CH2)2NCH2Cl][BF4]2 in MeCN gave [PtF(NCMe)Me2(DPK)][BF4]. In several cases, the ketone group of the DPK ligand took part in the reactions. For example, oxidation of [PtMe2(DPK)] by air or hydrogen peroxide gave [Pt(OH)Me2(DPKOH)] (DPKOH = κ3-NN′O-(2-C5H4N)2C(OH)O), which reacted with HCl to give [PtClMe2(DPKOH)] or with excess acetyl chloride to give [PtCl2Me2(DPK)]. Reaction of [PtMe2(DPK)] with methyl triflate in MeCN solution gave [PtMe3(NCMe)(DPK)][OTf], which reacted with more MeOTf in the presence of base to give [PtMe3{DPC(OMe)2}][OTf], where DPC(OMe)2 = κ3-NN′O-(2-C5H4N)2C(OMe)2. Hydrolysis of [PtF(NCMe)Me2(DPK)][BF4] gave [Pt{NHC(=O)Me}Me2(DPKOH)], which crystallized in partially protonated form as an unusual supramolecular polymer [Pt{NHC(=O)Me}Me2(DPKOH)]·0.5HBF4.Key words: platinum, oxidative addition, ketone, pyridyl.