PLATINUM(I) DIMERS AND PLATINUM(0) TRIANGLES WITH POLYAROMATIC PHOSPHINE LIGANDS

The metal-metal bonded platinum(I) dimers [Pt 2 Cl 2 (CO) 2 (PR 3 ) 2 ] (PR 3 = PNpPh 2 and PFc 2 Ph; Np = naphthyl, Fc = ferrocenyl) have been synthesised by reduction of the monometallic precursor [PtCl 2 (COD)] in the presence of CO and the appropriate phosphine. 31 P 1 H NMR studies have indicated the presence of a fluxional process which renders the two halves of this type of platinum dimer equivalent on the NMR timescale. Suggestions for a possible mechanism for this process are made on the basis of extended Huckel calculations. Slight variation of the reaction conditions lead to the isolation of the triangulo -cluster compounds [Pt 3 (μ-CO) 3 (PR 3 ) 3 ] (PR 3 = PNpPh 2 and PNp 2 Ph).

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