THE FIRST OSMABORANES AND A NEW IRIDATETRABORANE

Article abstract of DOI:10.1016/S0022-328X(00)98795-3

The reactions of under mild conditions with the anions arachno-^- and nido-^- yield the first air-stable polyhedral osmaborane species arachno<(HOsB3H8)(CO)(PPh3)2> (65percent) and nido-<(OsB5H9)(CO)(PPh3)2> (80percent) respectively.The 11B and 1H NMR properties of these osmaboranes are similar to those of their iridium analogues arachno-<(H2IrB3H8)(PPh3)2> (also previously unreported) and nido-<(IrB5H8)(CO)(PPh3)2>.Mild thermolysis of nido-<(OsB5H9)(CO)(PPh3)2> yields nido-<(OsB4H8)(CO)(PPh3)2> (40percent) for which there is, as yet, no iridium analogue.