Metal-substituted ketenes: first 13C and 31P CP/MAS NMR determinations

Cross-polarization, combined with magic-angle spinning, has been employed to obtain high-resolution solid-state 13C and 31P NMR spectra of a series of solid, peculiar ketenes, also known as η1-ketenyl derivatives, bearing as substituents a PPh3 moiety and a coordinatively unsaturated Pt(II) fragment. Solid-state NMR data found for trans-[PtCl2(η2-C2H4){η1-C(PPh3)CO}], trans-[PtCl2{η1-C(PPh3)CO}2], Ph3PCCO, trans-[PtCl2(η2-C2H4){η1-CH(PPh3)COMe}], trans-[PtCl2{η1-CH(PPh3)COMe}2] and Ph3PCHCOMe, are compared with NMR values obtained in solution. The general utility of the CP/MAS NMR technique in the study of unstable or insoluble complexes is discussed.