Expansion of iridaborane clusters by addition of monoborane. Novel metallaboranes and mechanistic detail
| Autor: | Sundargopal Ghosh, Bruce C. Noll, Thomas P. Fehlner |
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| Jazyk: | angličtina |
| Rok vydání: | 2008 |
| Předmět: |
Models
Molecular Magnetic Resonance Spectroscopy Molecular Structure Boron compounds Characterization Crystallography Organometallics Synthesis (chemical) Exopolyhedral adducts Exopolyhedral bridging Metallaboranes Iridium compounds Chemistry Temperature chemistry.chemical_element Reference Standards Borane Crystallography X-Ray Iridium Adduct Characterization (materials science) Inorganic Chemistry chemistry.chemical_compound Group (periodic table) Atom Organometallic Compounds Boranes Boron Electron counting Cluster expansion |
| Zdroj: | IndraStra Global. |
| ISSN: | 2381-3652 |
| Popis: | This work reports the results of a thermally driven cluster expansion of arachno-1-{?5-C5Me5IrH2}B 3H7, 1, with BH3�THF. In addition to the previously reported product, arachno-1-{?5-C5Me 5IrH}B4H9, 2, formed at lower temperatures, reaction at 100 �C permits the isolation of four new iridaboranes. Two products, nido-1-(?5-C5Me5Ir)B 5H9, 3, and nido-3-(?5-C5Me 5Ir)B9H13, 4, contain a single Ir atom and five and nine framework boron atoms, respectively. One, nido-3,4-(?5- C5Me5Ir)2B8H12, 5, contains two Ir atoms and eight framework boron atoms. Their structures are predicted by the electron counting rules to be a nido-iridahexaborane, 3, nido-iridadecaborane, 4, and nido-diiridadecaborane, 5. The accuracy of these predictions in each case is established experimentally by spectroscopic characterization in solution and structure determinations in the solid state. A less stable metallaborane has been identified and the available spectroscopic and crystallographic information are consistent with the formulation nido-3,4-(?5-C5Me5Ir)2B 8H13(?-BH2), 6, i.e., a species containing an exopolyhedral bridging BH group. These new observations, along with earlier ones on ruthenaborane cluster systems, are used to fully define a general mechanism for a cluster expansion reaction, i.e., addition of borane to form an exopolyhedral adduct followed by cage insertion. � The Royal Society of Chemistry. |
| Databáze: | OpenAIRE |
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