Triosmium clusters with ligands derived from αβ-unsaturated ketones. X-ray crystal structures of [Os3H(CO)10(cis-MeCCHCOMe)] and [Os3H(OH)(CO)9(PMe2Ph)]

Publisher Website
Google Scholar
Abstract
The compounds [Os3H2(CO)10] and [Os3(CO)10(MeCN)2] both react with the enones RCHCHCOMe (R = H, Me, or Ph) by metallation at the vinylic C–H groups to give compounds of type [Os3H(CO)10-(RC4H4O)], certain of which were also obtained from [Os3H2(CO)10] and CHCCOMe. Three isomers of [Os3H(CO)10(C4H5O)] were isolated, containing CH2 CCOMe and cis- and trans-CHCHCOMe respectively. The most stable isomer, [Os3H(CO)10(cis-CHCHCOMe)], is decarbonylated at 130 °C to give [Os3H(CO)9(cis-CHCHCOMe)] and contains a linear Os3 chain and a terminal hydride replaceable by Cl from CCl4. The substituted compounds [Os3H(CO)10(cis-RCCHCOMe)](R = Me or Ph) have a different structure; crystals of the compound with R = Me are monoclinic, space group C2/c, with a= 17.377(2), b= 14.293(2), c= 16.476(2)Å, β= 91.79(3)°, and Z= 8. The structure was solved via the heavy-atom method and refined to R= 0.034 using 2 906 diffractometer data with l 1.5σ(l). The structure is based on that of [Os3(CO)12] with a chelating MeCCHCOMe ligand occupying an axial and an equatorial site. The bridging hydride is not replaced by Cl in CCl4 solution. Unable to obtain good crystals of [Os3H(CO)10(cis-CHCHCOMe)], [Os3H2(CO)9(PMe2Ph)] was treated with CH2 CHCOMe in an attempt to obtain a PMe2Ph-substituted derivative but instead [Os3H(OH)(CO)9(PMe2Ph)], was obtained, the crystals of which are monoclinic, space group P21/n, with a= 17.535(2), b= 9.500(1), c= 14.326(2)Å, β= 101.86(1)°, and Z= 4. The structure was solved by the heavy-atom method and refined to R= 0.041 using 3 474 diffractometer data with l 1.5σ(l).

This publication has 0 references indexed in Scilit: