Reactions of heterometallic tungsten–iridium and tungsten–rhodium complexes containing C4 chains

Modified syntheses of {Cp(OC)3W}CCCC{M(CO)(PPh3)2} (M=Rh, Ir) from W(CCCCH)(CO)3Cp and M(OTf)(CO)(PPh3)2 are described. The Group 9 metal centre is the most electron-rich site, readily adding MeI or C2(CN)4. Reactions with iron carbonyls give successively {Cp(OC)3W}CCC2{Fe2M(CO)8(PPh3)} and {Cp(OC)8Fe2W}C2C2{Fe2M(CO)8(PPh3)}, in which Fe2(CO)6 moieties add to a CC group and the adjacent metal centre. X-ray structures of {Cp(OC)3W}CCCC{Rh(CO)[η-C2(CN)4](PPh3)2}, {Cp(OC)3W}CCC2{Fe2Rh(CO)8(PPh3)} and {Cp(OC)8Fe2W}C2C2{Fe2Ir(CO)8(PPh3)} have been determined.