@article {2392, title = {Theoretical study of the electronic spectra of s-triazine vapour}, journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie}, volume = {87}, number = {8}, year = {2009}, note = {ISI Document Delivery No.: 493VQTimes Cited: 3Cited Reference Count: 37Chong, Delano P.}, month = {Aug}, pages = {1148-1153}, type = {Article}, abstract = {The ionization and excitation spectra of valence and core electrons of s-triazine in the gas phase are studied with ab initio, density functional, and semi-empirical methods. The results are compared with available experimental data and previous calculations. New estimates are proposed for the ionization energies of both valence and core electrons. The calculated excitation energies are consistent with experiment.}, keywords = {AB-INITIO, AZINES, core-electron binding energies, DENSITY-FUNCTIONAL THEORY, DFT, electron spectra, ESCA, EXCHANGE-CORRELATION POTENTIALS, EXCITATION-ENERGIES, excitations, HYDROGEN, IONIZATION-POTENTIALS, ionizations, MOLECULAR CALCULATIONS, N-2, photoelectron spectra, s-triazine, SPECTROSCOPY, UV absorption}, isbn = {0008-4042}, url = {://000269766800008}, author = {Chong, D. P.} } @article {1253, title = {Activation and cleavage of alkynes by the dinuclear tantalum complexes ([NPN]Ta)(2)(mu-H)(4) and ([NPN]Ta)(2)(mu-eta(1):eta(2)-N-2)(mu-H)(2) (where NPN = PhP(CH2SiMe2NPh)(2))}, journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie}, volume = {83}, number = {6-7}, year = {2005}, note = {ISI Document Delivery No.: 963UVTimes Cited: 4Cited Reference Count: 29}, month = {Jun}, pages = {652-660}, type = {Article}, abstract = {Reaction of phenylacetylene with the dinuclear tetrahydride complex ([NPN]Ta)(2)(mu-H)(4) gives the product ([NPN]Ta)(2)(mu-PhCCH)(mu-H)(2) (where NPN is PhP(CH2SiMe2NPh)(2)). Activation of other terminal alkynes by ([NPN]Ta)(2)(mu-H)(4) accesses ([NPN]Ta)(2)(mu-RCCH)(mu-H)(2) (R = n-Pr, t-Bu). Crystallographic analysis of the R = Ph derivative showed it to be a bis(mu-alkylidene) bound asymmetrically to the two tantalum centres. Storage of solutions of ([NPN]Ta)(2)(mu-PhCCH)(mu-H)(2) under vacuum promotes the loss of H-2 and cleavage of the C-C bond to give a bis(mu-alkylidyne) complex, ([NPN]Ta)(2)(mu-CPh)(mu-CH). Addition of diphenylacetylene did not give the desired ([NPN]Ta)(2)(mu-CPh)(2), but rather promotes a complex decomposition of the supporting [NPN] ligands. Reaction of phenylacetylene with the dinitrogen complex ([NPN]Ta)(2)(mu-eta(1):eta(2)-N-2)(mu-H)(2) results in the dissociation of the bound dinitrogen and the formation of ([NPN]Ta)(2)(mu-PhCCH)(mu-H)(2), which is identical to that derived from the reaction with the dinuclear tetrahydride.}, keywords = {activation of small molecules, alkylidene, alkylidyne, ALKYLIDYNE COMPLEXES, ALKYNE, amidodiphosphine, BONDS, DIAMIDOPHOSPHINE COMPLEXES, DINITROGEN CLEAVAGE, DINUCLEAR, END-ON, FUNCTIONALIZATION, hydride dinitrogen, LIGAND, N-2, NIOBIUM(III), SIDE-ON, tantalum}, isbn = {0008-4042}, url = {://000231832500020}, author = {Shaver, M. P. and Johnson, S. A. and Fryzuk,Michael D.} } @article {1185, title = {Functionalization and cleavage of coordinated dinitrogen via hydroboration using primary and secondary boranes}, journal = {Canadian Journal of Chemistry-Revue Canadienne De Chimie}, volume = {83}, number = {4}, year = {2005}, note = {ISI Document Delivery No.: 921DLTimes Cited: 14Cited Reference Count: 30}, month = {Apr}, pages = {315-323}, type = {Article}, abstract = {The reaction of the side-on, end-on ditantalum dinitrogen complex ([NPN]Ta)(2)(mu-eta(1):eta(2)-N-2)(mu-H)(2) (where NPN = PhP(CH2SiMe2NPh)(2)) with a variety of secondary and primary boranes is reported. With 9-BBN, hydroboration of the Ta2N2 unit occurs via B-H addition, which in turn triggers a cascade of reactions that result in N-N bond cleavage, ancillary ligand rearrangement involving silicon group migration, and finally elimination of benzene from the N-Ph group and a B-H moiety to generate the imide-nitride derivative. In the presence of excess 9-BBN, the Lewis acid - base adduct of the imide-nitride ([NP mu-N]Ta(=NBC8H14)(mu-NB(H)C8H14)Ta[NPN]) is formed. A similar set of reactions is observed for dicyclohexylborane (Cy2BH), which hydroborates the dinitrogen complex to generate [NPN]Ta(H)(mu-eta(1):eta(2)-NNBCy2)(mu-H)(2)Ta[NPN], followed by loss of H-2 and silicon group migration to yield the imide-nitride [NP mu-N]Ta(=NBCy2)(mu-N)(Ta[NPN]. With thexyl borane (H2BCMe2CHMe2), a similar sequence of reactions is suggested starting with hydroboration to generate [NPN]Ta(H)(mu-eta(1):eta(2)-NNB(H)C6H13)(mu-H)(2)Ta[NPN], followed by loss of H-2 and ancillary ligand rearrangement. When bis(pentafluorophenyl)borane (HB(C6F5)(2)) is used, no hydroboration of coordinated N-2 is observed, rather simple adduct formation to give ([NPN]Ta)(2)(mu-eta(1):eta(2)-NN-B(H)(C6F5)(2))(mu-H)(2) occurs.}, keywords = {ACTIVATION, ammonia, CHEMISTRY, DINITROGEN, END-ON, FIXATION, hydroboration, METAL-COMPLEXES, MOLECULAR NITROGEN, MOLYBDENUM, N-2, N-N bond cleavage, SIDE-ON, tantalum}, isbn = {0008-4042}, url = {://000228744300008}, author = {MacKay, B. A. and Johnson, S. A. and Patrick, B. O. and Fryzuk,Michael D.} } @article {1186, title = {Hydroalumination of a dinuclear tantalum dinitrogen complex: N-N bond cleavage and ancillary ligand rearrangement}, journal = {Organometallics}, volume = {24}, number = {16}, year = {2005}, note = {ISI Document Delivery No.: 949ZKTimes Cited: 15Cited Reference Count: 32}, month = {Aug}, pages = {3836-3841}, type = {Article}, abstract = {The addition of diisobutylaluminum hydride (DIBAL) to the side-on end-on dinitrogen complex ([NPN]Ta)(2)(mu-eta(1):eta(2)-N-2)(mu-H)(2), 1 (where [NPN] = (PhNSiMe2CH2)(2)PPh), is described. The two end products are diastereomeric rotational isomers in which N-N bond cleavage has occurred with an Al(Bu-i)H group attached to one of the nitride atoms. The reaction proceeds through addition of DIBAL to 1 to generate a thermally sensitive intermediate that has been characterized in solution as the result of Al-H addition across the TaN2 moiety, namely, ([NPN]TaH)(mu-eta(1):eta(2)-NNA1(i)Bu(2))(mu-H)(2)(Ta[NPN), 2. This material subsequently rearranges via a second thermally labile intermediate to ultimately generate two diastereomeric end products that show N-N bond cleavage, loss of H-2, loss of an aluminum isobutyl group, and NPN ligand migration from tantalum to aluminum. Both of these complexes have been isolated in crystalline form and analyzed by single-crystal X-ray diffraction. The second thermally sensitive intermediate has been characterized on the basis of multinuclear NMR spectroscopy as ([NPN]TaH)(mu-eta(1):eta(2)-(NNAlBu)-Bu-i(mu-H))(mu-H)(2)(Ta[NPN), 3.}, keywords = {ACTIVATION, ATMOSPHERIC NITROGEN, CHEMISTRY, COORDINATED DINITROGEN, END-ON, FUNCTIONALIZATION, METAL-COMPLEXES, MOLECULAR NITROGEN, N-2, SIDE-ON}, isbn = {0276-7333}, url = {://000230827200007}, author = {MacKay, B. A. and Patrick, B. O. and Fryzuk,Michael D.} } @article {947, title = {Carbon-nitrogen bond formation via the reaction of terminal alkynes with a dinuclear side-on dinitrogen complex}, journal = {Journal of the American Chemical Society}, volume = {126}, number = {31}, year = {2004}, note = {ISI Document Delivery No.: 843TSTimes Cited: 27Cited Reference Count: 21}, month = {Aug}, pages = {9480-9481}, type = {Article}, keywords = {ACTIVATION, COORDINATION, FIXATION, FUNCTIONALIZATION, HETEROCYCLES, HYDROAMINATION, METAL-COMPLEXES, MOLECULAR NITROGEN, MOLYBDENUM, N-2}, isbn = {0002-7863}, url = {://000223110100007}, author = {Morello, L. and Love, J. B. and Patrick, B. O. and Fryzuk,Michael D.} } @article {617, title = {Dinuclear organometallic dinitrogen complexes of niobium}, journal = {Inorganica Chimica Acta}, volume = {345}, year = {2003}, note = {ISI Document Delivery No.: 653EUTimes Cited: 4Cited Reference Count: 30}, month = {Mar}, pages = {53-62}, type = {Article}, abstract = {{The niobium(III) chloride precursors (R)[P2N2]NbCl stabilized by the bis-(amidophosphine) macrocycle (where (R)[P2N2] RP(CH2SiMe2NSiMe2CH2)(2)PR}, keywords = {ACTIVATION, amidophosphine ligands, AZOBENZENE, CLEAVAGE, CRYSTAL-STRUCTURE, CRYSTALLOGRAPHY, DINITROGEN COMPLEXES, END-ON, FIXATION, fluxionality, macrocycle, macrocycles, N-2, NIOBIUM, NITRIDE, SIDE-ON}, isbn = {0020-1693}, url = {://000181422900008}, author = {Fryzuk,Michael D. and Kozak, C. M. and Patrick, B. O.} }