Isolation and structural characterisation of products from the reaction of [Os4(µ-H)4(CO)10(MeCN)2] with cyclohexa-1,3-diene
Abstract
The activated tetraosmium hydrido cluster, [Os4(µ-H)4(CO)10(MeCN)2]1, reacts with cyclohexa-1,3-diene producing a range of tetraosmium derivatives including the known clusters [Os4(µ-H)3(CO)11(µ-η1 : η2-C6H9)]2, [Os4(µ-H)2(CO)12(η2-C6H8)], [Os4(µ-H)2(CO)11(η4-C6H8)], [Os4(µ-H)2(CO)10(η6-C6H6)] and [Os4(CO)9(η4-C6H8)(η6-C6H6)], and the new complexes [Os4(µ-H)(CO)10(µ3-η1 : η2 : η1-C6H8)(η3-C6H9)]3, [Os4(µ-H)2(CO)10(η6-C6H5C6H9)]4 and [Os5(µ-H)2(CO)13(η4-C6H8)]5. The molecular structure of clusters 3,4 and 5 has been determined by single-crystal X-ray diffraction analysis, and an extensive 1H NMR study of the cyclohexyne–allyl cluster, 3, has been described. The conversion of the cyclohexenyl cluster, [Os4(µ-H)3(CO)11(µ-η1 : η2-C6H9)]2, into the new cyclohexyne complex, [Os4(µ-H)2(CO)11(µ3-η1 : η2 : η1-C6H8)]6, by loss of dihydrogen is also described.