Chemistry of di- and tri-metal complexes with bridging carbene or carbyne ligands. Part 45. Synthesis of the pentanuclear metal complexes [M′M2Re2(µ-CC6H4Me-4)2(CO)18](M′= Ni or Pt, M = Cr or W) and related compounds; X-ray crystal structure of [ReWPt(µ-CC6H4Me-4)(CO)9(PMe3)2

Abstract

The pentanuclear metal compounds [M′M2Re2(µ-CC6H4Me-4)2(CO)18](M′= Pt or Ni, M = Cr or W) have been prepared by treating the complexes [ReM(CC6H4Me-4)(CO)9] with [Pt(C2H4)3] Or [Ni(cod)2](cod = cyclo-octa-1,5-diene), respectively. Similarly, the species [ReM(CC6H4Me-4)(CO)9] react with the platinum compounds [Pt(C2H4)2{P(cyclo-C6H11)3}] and [Pt(C2H4)(PMe3)2] to afford the trimetal complexes [ReWPt(µ-CC6H4{Me-4)(CO)10{P(cyclo-C6H11)3}] and [ReMPt(µ-CC6H4Me-4)(CO)9(PMe3)2](M = Cr or W), respectively. An X-ray diffraction study on the compound [ReWPt(µ-CC6H4Me-4)(CO)9(PMe3)2] shows that the molecule has a bent Re–W–Pt [151.3(1)°] spine, with metal–metal distances Re–W 3.082(1) and W–Pt 2.771(1)A. The W–Pt bond is bridged by the CC6H4Me-4 group [µ-C–W 2.01 3(24), µ-C–Pt 1.962(23)A]. The rhenium atom is ligated by five CO groups orthogonally disposed, so that the metal is in an octahedral environment, the sixth site being occupied by the Re–W bond. The platinum atom carries the two PMe3 ligands [P–Pt–P 98.6(2)°] and the tungsten atom four CO groups. The latter are radially disposed so that the tungsten is in a distorted octahedral environment with respect to these CO ligands; the Re(CO)5 group, and the mid-point of the µ-C–Pt bond [Re–W–µ-C 163.1(6), Re–W–Pt 151.3(1)°]. The radial CO groups on rhenium and tungsten are staggered with respect to each other about the Re–W bond.