103498-16-4Relevant academic research and scientific papers
Comparative Ten-vertex Metallaborane Chemistry: Some nido-6-Metalladecaboranes of Tungsten, Rhenium, Ruthenium, Osmium, and Iridium; including the Crystal and Molecular Structures of and
Beckett, Michael A.,Greenwood, Norman N.,Kennedy, John D.,Thorton-Pett, Mark
, p. 795 - 802 (2007/10/02)
Reaction of with yields the first wolfraborane, ; the halcyon-blue air-stable compound has been characterised by a single-crystal X-ray diffraction analysis and by n.m.r. spectroscopy.Crystals are monoclinic, space group P21/n, with a=1571.7(5), b=1049.1(5), c=1961.5(8) pm, β=94.30(3) deg, and Z=4.The molecular structure closely resembles that of nido-B10H14 with the BH unit at position 6 being subrogated by a WH2(PMe2Ph)3 metal centre.In solution the compound exhibits fluxionality of the five exo-polyhedral ligands (PMe2Ph)3H2 on the metal centre.Reaction of mer- with yields the new red air-stable osmaborane which has also been characterized by a single-crystal X-ray diffraction analysis and n.m.r. spectroscopy.Crystals are monoclinic, space group P21/c, with a=957.8(1), b=1990.0(4), c=1671.4(3) pm, β=94.01(1) deg and Z=4.The structure comprises nido-decaborane-like molecules in which the 6-BH unit has been subrogated by the isolobal Os(PMe2Ph)3 unit.The analogous reaction with mer- yields the new dark amber ruthenaborane , and with and the previously reported rhenaborane is formed in an improved yield of 65percent.The new tungsten and osmium species together with the known nido-6-metalladecaboranes and (R=Me or Ph) permit the structural and n.m.r. comparison of the metallaboranes across four adjacent groups of the Periodic Table; the systematic variation of the exo-polyhedral metal ligands across the sequence WH2(PMe2Ph)3, ReH(PMe2Ph)3, Os(PMe2Ph)3, IrH(PR3)2 implies that each 18-electron metal centre is a three-orbital two-electron contributor to the cluster bonding, just like 6-BH in the structural parent nido-B10H14.For the compounds studied there is a progressive diminution of ca. 5 pm per elemental step in both the M-B and M-P interatomic distances across the series W, Re, Os, Ir, but the 11B and 1H n.m.r. properties indicate that the cluster bonding retaines essentially nido-decaborane-like behaviour throughout.
