Reactions of the organoplatinum complex [Pt(cod) (neoSi)Cl] (neoSi = trimethylsilylmethyl) with the non-coordinating anions SbF₆– and BPh₄–

Abstract

Reactions of the organoplatinum complex [Pt(cod)(neoSi)Cl] (neoSi = (trimethylsilylmethyl) with the Ag(I) salts of oxo or fluoride containing anions A– = NO3–, ClO4–, OTf – (trifluoromethanesulfonate) and SbF6– lead to the desired abstraction of the chlorido ligand and precipitation of AgCl. However, further reaction of the resulting Pt complexes [Pt(cod)(neoSi) (solvent)]+ with diverse N-heterocyclic ligands L such as pyridines, caffeine, and guanine did not yield the targeted complexes [Pt(cod)(neoSi)(L)](A) in most of the cases, but to extensive decomposition yielding [Pt(cod)(Me) (solvent)]+, thus transforming the neoSi into a methyl ligand. A detailed study on the reaction with SbF6– combining DFT calculations with NMR and MS revealed that Pt catalysed decomposition of SbF6‒ and fluorination of the neoSi silicon atom leading to FSiMe3. When reacting the parent complex with Ag(BPh4), the arylated derivative [Pt(cod)(neoSi)(Ph)] was obtained and characterised by multinuclear NMR, MS and single crystal XRD.

Platinum(II) Di-ω-alkenyl Complexes as “Slow-Release” Precatalysts for Heat-Triggered Olefin Hydrosilylation

“…For the PtR 2 (diene) compounds, the similarity of the olefinic 1 H and 13 C NMR chemical shifts to those of free alkenes, and the absence of Pt−H or Pt−C couplings to the CH 2 group clearly show thatunlike the PtR 2 compounds 1 and 2the terminal CC bonds in the ωalkenyl ligands are not coordinated to Pt. As seen in other Pt II alkyls, there are long-range 3 J PtC couplings 30,31 of ca. 30 Hz to the vinyl Si−CH carbon in 1-COD, the allylic Si-CH 2 carbon in 2-COD, and to the Si-Me carbon atoms in both compounds.…”