Extrusion of selenium and tellurium atoms from selenophene and tellurophene by reaction with trinuclear iron, ruthenium, and osmium clusters: crystal structures of 3-Se)(μ4-C4H3)(CO)20> and of 3-Se)(μ-C4H4)(CO)11>

Article abstract of DOI:10.1016/0022-328X(91)86164-L

The trinuclear carbonyl clusters , , , and react with selenophene and tellurophene (cyclo-C4H4X, X = Se or Te) under mild conditions to give compounds containing the open-chain ligands CHCHCHCHX or the fragments X, C4H4, C4H3, or H as bridging ligands.The following compounds were isolated and characterised: , 1 where X = Se (X-ray structure reported previously) and 8 where X = Te, , 2, , 3, , 4, , 5, , 6, and , 7.The clusters 2 and 5 were shown by single-crystal X-ray diffraction methods to have had both Se-C bonds broken to give μ₃-Se ligands in each case.Compound 2 contains an interesting μ₄-C4H3 ligand linking two Os3 units through a μ-alkylidyne bridge, a ?-Os-C bond, and an η³-allyl component.Compound 5 has a μ-C4H4 ligand of a type previously found to be formed by alkyne coupling.The other compounds were characterised spectroscopically.