Krinsky, Jamin L. Anderson, Laura L. Arnold, John Bergman, Robert G. Oxygen-Centered Hexatantalum Tetradecaimido Cluster Complexes The syntheses and characterization of several octahedral hexatantalum cluster compounds of formula (ArN)<sub>14</sub>Ta<sub>6</sub>O are described (Ar = Ph, <i>p</i>-MeC<sub>6</sub>H<sub>4</sub>, <i>p</i>-MeOC<sub>6</sub>H<sub>4</sub>, <i>p</i>-<i>t</i>-BuC<sub>6</sub>H<sub>4</sub>, <i>p</i>-BrC<sub>6</sub>H<sub>4</sub>, <i>m</i>-ClC<sub>6</sub>H<sub>4</sub>). Treatment of Bn<sub>3</sub>TaN-<i>t-</i>Bu (Bn = CH<sub>2</sub>C<sub>6</sub>H<sub>5</sub>) or pentakis(dimethylamido)tantalum with an excess of the appropriate aniline and stoichiometric water or tantalum oxide afforded varying yields of arylimido clusters. The structures of two species were confirmed by X-ray diffraction (XRD), while the identity of the central oxygen atom was elucidated by electrospray mass spectrometry (MS) using <sup>17</sup>O/<sup>18</sup>O-enriched material. The title species are very air- and moisture-sensitive but quite thermally stable in solution. Experimentally determined optical properties and oxidation/reduction potentials, as well as some computational results, indicate that they possess an electronic structure wherein the highest occupied molecular orbitals are ligand-centered, while the lowest unoccupied orbitals are metal-centered and delocalized throughout the tantalum cage. Whereas chemical oxidation resulted in cluster decomposition, reduction with decamethylcobaltocene yielded stable salts of formula [Cp*<sub>2</sub>Co][(ArN)<sub>14</sub>Ta<sub>6</sub>O] (Ar = Ph, Ar = <i>p</i>-MeC<sub>6</sub>H<sub>4</sub>). Small-molecule reactivity studies on one of these clusters showed that its imido functionalities are moderately reactive toward oxide donors but inert with respect to metallaheterocycle-forming processes. Clean imido/oxo exchange was observed with aldehydes and ketones, leading cleanly to organic imines with no soluble byproducts being observed. This exchange was also observed with a rhenium oxo compound (generating an imidorhenium complex as the only soluble species). All 14 imido groups were transferred in these reactions, and no mixed-ligand cluster intermediates were ever observed. electrospray mass spectrometry;Bn;chemical oxidation;title species;rhenium oxo compound;14 imido groups;BuC 6 H 4;ClC 6 H 4;CH 2 C 6 H 5;Ph;tantalum cage;arylimido clusters;formula;XRD;MeC 6 H 4;MS;MeOC 6 H 4;imido functionalities;cluster decomposition;14 Ta 6 O;BrC 6 H 4;orbital;stoichiometric water;tantalum oxide;octahedral hexatantalum cluster compounds;oxygen atom;oxide donors;Ar 2008-02-04
    https://acs.figshare.com/articles/dataset/Oxygen_Centered_Hexatantalum_Tetradecaimido_Cluster_Complexes/2959873
10.1021/ic701920v.s012