Dimerisation of a diplatinum to a tetraplatinum complex during catalysis of the water gas shift reaction: the X-ray crystal structure of [Pt4(µ2-CO)2(µ2-Ph2PCH2PPh2)3{Ph2PCH2P(:O)Ph2}]

Abstract

The binuclear complex [Pt₂H₂(µ-dppm)₂][PF₆], dppm = Ph₂PCH₂PPh₂, is an active catalyst precursor for the water gas shift reaction, especially at low pressures of carbon monoxide; the catalytic solutions are shown to contain cluster complexes such as the tetranuclear [Pt₄(µ-CO)₂(µ-dppm)₃{Ph₂PCH₂P(:O)Ph₂}], whose ‘butterfly’ structure has been determined by X-ray crystallography.