500205-50-5Relevant articles and documents
The mechanism of olefin exchange in platinum(0) pyridyl-methanimine and pyridyl-thioether complexes. A kinetic study
Canovese, Luciano,Visentin, Fabiano,Chessa, Gavino,Santo, Claudio,Uguagliati, Paolo,Maini, Lucia,Polito, Marco
, p. 3696 - 3704 (2007/10/03)
The complexes of type [Pt(η2-ol1)(L-L′)] (ol1 = dimethylfumarate (dmf), naphthoquinone (nq); L-L′ = pyridyl-methanimine (N-N′R′; R′ = Bu′, 4-MeOC6H4), pyridyl-thioether (N-SR; R = Bu′, Ph) ligands) were synthesised and fully characterised by means of spectrometric and spectroscopic techniques and elemental analysis. At variance with analogous palladium complexes which display a more complicated solution behaviour, the fluxional rearrangement of pyridyl-thioether platinum(o) olefin substrates occurs via inversion at sp3 sulfur only (L-L′ = N-SR). Moreover, the exchange olefin reactions between [Pt(η2-ol1)(L-L′)] complexes and the entering olefi ol2 [ol2 = maleic anhydride (ma), fumaronitrile (fn), naphthoquinone (nq) and tetramethylethylenetetracarboxylate (tmetc)] were studied in CHCl3 either under pseudo-first order or second order conditions. On the basis of the ensuing results and of the activation parameters, an associative reaction mechanism is proposed and a novel reactivity scale for the electron poor olefins acting as entering species is determined. The crystal structures of the complexes [Pt(η2-ol)(L-L′)] (ol= fn, ma, dmf) were also determined and compared with those of analogous platinum(o) and palladium(o) species.
