Cyclooctadienemethylplatinum complexes: synthesis, reactivity, molecular structure and spectroscopic properties of the organometallic hydroxoplatinum(II) complex [(COD)PtMe(OH)]

Labile Pd-sulphur and Pt-sulphur bonds in organometallic palladium and platinum complexes [(COD)M(alkyl)(S-ligand)]n+—A speciation study

“…The Pt II ion in both structures exhibits completely square planar stereochemistry, taking the centroids of the C=C olefin bond, the methyl coligands and the S atom of the S ligand, giving an almost perfect sum of angles around Pt (Table 3). Overall, the bonding parameters of the two complexes such as the X-Pt-X angles and the Pt-X and PtMe bond lengths are very similar to related [(COD)Pt(Me)] complexes [43][44][45][46][47]49,50,52,[90][91][92]. The same is true of the Pt-S bonds when compared with similar complexes [50,52,79,91].…”

“…From earlier studies it is well known that the 2 J Pt,H(=CH,COD) coupling constants reflect very well the general Pt-ligand bond strength of a ligand trans to the corresponding olefin proton in COD-Pt complexes [43][44][45][46][49][50][51] (COD = 1,5-cyclooctadiene). Table 1 2 ] is reported to be 56 Hz [79].…”

“…The synthesis of the cationic Pt and Pd complexes was carried out as previously reported for related complexes [43][44][45][46][47][48][49] [48]. Although the binding of cysteinate to Pt II complexes [Pt(N^N^N)Cl] + with tridentate ligands such as 2,2′:6′,2″-terpyridine (terpy) [16,23,[31][32][33][34][35][36][37][38] or diethylene-triamine (dien) [22,[36][37][38][39][40] has been studied intensively, no evidence for a binuclear cysteinate-bridged species [(μ-Cys){Pt(N^N^N)} 2 ] 3+ was found.…”

“…For a more defined approach to assess the binding strength of various sulphur ligands (with or without biological relevance), complex scaffolds [(terpy)Pt] 2+ (terpy = 2,2′:6,2″-terpyridine) [16,23,[31][32][33][34][35][36][37][38] and [(dien)Pt] 2+ (dien = diethylene-triamine) [22,[36][37][38][39][40] with only one coordination site, have been frequently studied, in the latter case also the Pd derivatives [36][37][38]41,42]. Recently, we have demonstrated the suitability of the [(COD)M(R)] (M = Pt or Pd; R = alkyl) fragment to coordinate various ligands [43][44][45][46][47][48][49][50][51]. For the platinum derivatives multinuclear NMR spectroscopy in addition to the determination of molecular structures has allowed an excellent insight into the binding between platinum and the introduced ligands [43][44][45][46][49][50][51].…”

“…Recently, we have demonstrated the suitability of the [(COD)M(R)] (M = Pt or Pd; R = alkyl) fragment to coordinate various ligands [43][44][45][46][47][48][49][50][51]. For the platinum derivatives multinuclear NMR spectroscopy in addition to the determination of molecular structures has allowed an excellent insight into the binding between platinum and the introduced ligands [43][44][45][46][49][50][51]. From the 1 H-195 Pt coupling constant of the trans-oriented olefin proton the bond strength could be quantified quite reliably.…”