Reactivity studies of monoacetylide species towards chalcogen-bridged mixed-metal clusters:: Synthesis and characterisation of [(η5-C5H5)2Fe2RuM2(CO)6(μ3-E)2{μ4-CC(Ph)C(Ph)C}] (M=Mo, W; E=S, Se) and [(η5-C5H5)2Fe2Ru2M2(CO)9(μ3-E)2{μ-CCPh}2] (M=W, E=S, Se)

Thermolysis of a toluene solution containing [Fe2Ru(CO)9(μ3-E)2] (E=S or Se) and [(η5-C5H5)M(CO)3(CCPh)] (M=Mo or W) results in coupling of monoacetylide ligands and formation of new mixed-metal clusters [(η5-C5H5)2Fe2RuM2(CO)6(μ3-E)2{μ4-CC(Ph)C(Ph)C}] (M=Mo, E=S 1 or Se 2; M=W, E=S 3 or Se 4) and [(η5-C5H5)2Fe2Ru2M2(CO)9(μ3-E)2{μ-CCPh}2] (M=W, E=S 5 or Se 6). Compounds 1–6 have been characterised by IR and 1H- and 13C-NMR spectroscopy. Structures of 1 and 5 have been established crystallographically. Compound 1 features a tail-to-tail type of coupling of two acetylide groups on a Fe2RuMoS2 core and compound 5 is a hexanuclear Fe–Ru–W mixed-metal cluster with two uncoupled acetylide groups.