Synthesis and characterization of hexaosmium carbonyl clusters containing pyridine ligands: crystal and molecular structures of [Os6(CO)15(µ4-η2-CO)(C5H5N)3], [Os6(CO)15(µ-H)(µ-CO)(µ3-O)(C5H5N)(µ-η2-NC5H4)] and [Os6(CO)14(µ-H)(µ-CO)(MeCN)(C5H5N)(µ-η2-NC5H4)]

Abstract

Reaction of [Os₆(CO)₁₆(MeCN)₂] with 1 equivalent of pyridine in CH₂Cl₂ at room temperature afforded three new clusters: [Os₆(CO)₁₅(µ₄-η²-CO)(C₅H₅N)₃] 1, [Os₆(CO)₁₅(µ-H)(µ-CO)(µ₃-O)(C₅H₅N)(µ-η²-NC₅H₄)] 2 and [Os₆(CO)₁₄(µ-H)(µ-CO)(MeCN)(C₅H₅N)(µ-η²-NC₅H₄)] 3 in 32, 10 and 25% yields respectively. Both clusters 2 and 3 contain an orthometallated pyridine ligand but with different metal core geometries. The molecular structure of cluster 2 revealed the presence of a novel µ₃-O group bridging three osmium centres.