This thesis describes the synthesis and chemistry of triangular phosphido-bridged iridium clusters. The cluster [Ir3(μ-PPh2)3 (CO)6] was obtained analytically pure for the first time. In the solid state this 48 electron cluster exhibits one short iridium-iridium bond of 2.6702(3) Å and two long iridium-iridium bonds, 2.9913(3) Å on average. Two phosphido bridges rest closely within the plane of the metal triangle while the unique phosphido group, bridging the short metal-metal bond, is almost orthogonal to this plane. NMR data suggest that this structure is also adopted in solution below 183 K. At higher temperature however the phosphido bridges give rise to an average signal which is presumably due to a rapid flip-flop motion of these groups. Addition of one molar equivalent of dimethylacetylendicarboxylate to [Ir3(μ-PPh2)3(CO)6] results in formation of [Ir3(μ-PPh2)3(CO) 6(μ-DMAD)] which contains a diiridacyclobutene. Addition of excess alkyne leads to the CO-inserted [Ir3(μ-PPh2) 3(CO)5(μ-DMAD){κ2-MeO 2CCC(CO2Me)C(O)}] which photochemically decarbonylates, to give [Ir3(μ-PPh2)3(CO)5(μ-DMAD) 2]. The 50 electron cluster [Ir3(μ-PPh2) 3(CO)5(t-BuNC)2] also reacts with dimethylacetylendicarboxylate to yield the CO-inserted [Ir3(μ-PPh2)3(CO) 3(t-BuNC)2{κ2-MeO2CCC(CO 2Me)C(O)}2] in two isomeric forms. The new CO-insertion products represent stable iridacyclobutenones which are reluctant to undergo further insertion reactions involving carbon monoxide, tert-butylisocyanide or dimethylacetylenedicarboxylate. Addition of dimethylacetylendicarboxylate to cluster mixtures containing predominantly [Ir2Rh(μ-PPh2)3(CO) 5] and [Ir3(μ-PPh2)3(CO)6] results in selective reaction at the tri-iridium cluster which allowed for the isolation of the heterometallic cluster by chromatography. In contrast to the tri-iridium parent, [Ir2Rh(μ-PPh2)3(CO) 5] is much less reactive to dimethylacetylendicarboxylate and inert to CO. Similarly, the heterometallic [Ir2Rh(μ-PPh2) 3(CO)4(RNC)3] (R = tert-butyl; 1,1,3,3-tetramethylbutyl) are reluctant to undergo oxidative addition reactions with dimethylacetylendicarboxylate and iodomethane which readily afford addition products with the homometallic parent clusters. The kinetic difference is a consequence of electronic rather than steric factors in the clusters. / Graduate

The synthesis of a variety of new lanthanoid phosphine complexes has been achieved by complexing either one or two amido-diphosphine ligands to yttrium, lutetium or lanthanum. At room temperature, the seven-coordinate bis(amido- diphosphine) complexes, MCl[N(SiMe₂CH₂PR₂)₂]₂- are fluxional and display NMR spectra indicative of complexes where the phosphorus donors are rapidly exchanging, probably via a dissociation-reassociation pathway. It is possible to generate thermally unstable hydrocarbyl complexes of the type, M(R)[N(SiMe₂CH₂PMe₂)₂]₂, which undergo a clean first order elimination of R-H to generate cyclometallated complexes of the type, M[N(SiMe₂CHPMe₂)(SiMe₂CH₂PMe₂)][N(SiMe₂CH₂PMe₂)₂]; the yttrium derivative was crystallographically characterized. These thermally robust compounds will undergo a-bond metathesis with H₂ and D₂ at high temperature, but appear to be too sterically congested to react with larger molecules. The synthesis of a series of mono(amido-diphosphine) lanthanoid complexes, MCl₂ [N(SiMe₂CH₂PR₂)₂], (R = Me, Ph, Pr', Bu[symbol omitted]) has also been achieved. Complexes of the type, MCl₂[N(SiMe₂CH₂PMe₂)₂], are insoluble in hydrocarbon solvents, presumably because they are oligomeric in nature. They will however, dissolve in THF probably forming seven-coordinate bis(THF) monomers. Attempts to alkylate these compounds generally led to decomposition; the cyclometallated bis(ligand) complex, M[N(SiMe₂CHPMe₂)(SiMe₂CH₂PMe₂)] [N(SiMe2CH2PMe2)2], was identified as the major product. A route to a dimeric mono(amido-diphosphine) allyl complex, {YCl(allyl)[N(SiMe₂CH₂PMe₂)₂]}₂ (characterized by crystallography) was found via the reaction of allyl-MgCl or Mg(allyl)₂(dioxane) with YCl[N(SiMe₂CH₂PMe₂)₂]₂. The mono(ligand) complexes containing bulky phosphine donors (R = Ph, Bu[symbol omitted], Pr[symbol omitted]) are soluble in hydrocarbon solvents; YCl₂[N(SiMe₂CH₂PPr[symbol omitted]₂)₂] can be isolated as either a THF adduct or as the base-free dimer. A new reaction, mediated by a zirconium or hafnium amido-diphosphine complex, where allyl and butadiene moieties are coupled together to generate a coordinated [ɳ⁴:ɳ¹-CH₂=CHCH=CHCH₂CH₂CH₂]¹- fragment has been investigated. The process is very sensitive to the nature of the ancillary ligands at the metal. For MCl(ɳ⁴-C₄H₆)[N(SiMe₂CH₂PR₂)₂] complexes, after the addition of allylMgCl, the transformation takes about one hour when M = Hf & R = Pr[symbol omitted], two hours when M = Zr & R = Pr[symbol omitted], a week when M = Hf & R = Me, and results only in decomposition when M = Zr & R = Me. Similarly, for the zirconium mediated coupling of 1-methylallyl with butadiene, when R = Me, decomposition occurs and when R = Pr[symbol omitted], after two hours the coupling is complete. Two of the four possible coupled products are formed in unequal amounts, and the coupling occurs exclusively at the substituted end of the 1-methylallyl unit as determined by X-ray crystallography. Which diastereomer is formed in excess was not determined. The reduction of ZrCl₃[N(SiMe₂CH₂PR₂)₂] (R = Pr[symbol omitted] or Bu[symbol omitted]) with Na/Hg amalgam under nitrogen results in the formation of a binuclear zirconium dinitrogen complex, {ZrCl[N(SiMe₂CH₂PR₂)₂]}₂ (μ-ɳ²:ɳ²-N₂). X-ray crystallography (for R = Pr[symbol omitted]) reveals that the N₂ ligand is symmetrically bound in a side-on fashion to both metals. In addition, the N—N bond length of 1.548 (7) Å, the longest bond length ever reported for a dinitrogen complex, indicates that the dinitrogen has been reduced to a N₂⁴⁻ hydrazido ligand. Protonation of the complex with HCl results in a quantitative formation of hydrazine. / Science, Faculty of / Chemistry, Department of / Graduate

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There is no abstract available for this thesis. / Department of Chemistry

The tricobalt cluster PhCCo₃(CO)₉ (1) reacts with the bidentate phosphine ligand 2,3-bis(diphenylphosphino)maleic thioanhydride (bta) with added Me₃NO to yield PhCCo₃(CO)₇(bta) (2), which upon heating overnight yields Co₃(CO)₆(μ₂-η²,η¹-C(Ph)C=C(PPH₂)C(O)SC(O)) (μ₂-PPh₂) (3). Cluster (3) has been isolated and characterized by FT-IR and ³¹P NMR spectroscopy. Structural determination of the cluster has been demonstrated by X-ray diffraction analysis. Cluster (3) is analogous to the cluster synthesized by Richmond and coworkers. The redox properties of (3) have been examined by cyclic voltammetry and the data are reported within.

Shaowu Wang. / "August 1999." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (p. 125-143). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Guofu Zi. / "June 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 164-173). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

本文成功地合成了碳碳相連的鳥巢型碳硼烷化合物[Me₃NH][7,8-O(CH₂)₂-7,8-C₂B₉H₁₀]，閉籠型碳硼烷衍生物1-(1-茚基)-1,2-碳硼烷以及一系列基於以上配體的稀土金屬配合物，同時研究並探討了這些化合物對不同不飽和有機化合物的反應性。 / 1-(1-茚基)-1,2-碳硼烷可通過碳硼烷二鋰鹽與相應環氧化合物反應後再脫水而製備。該配體與稀土烷基化合物發生酸碱反應生成相應的稀土碳硼烷化合物，[η⁵:σ-(C₉H₆)C₂B₁₀H₁₀]Ln[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂ (Ln= Y, Gd, Er, Dy)。這類稀土碳硼烷化合物的反應性也被相繼研究。它可以跟各種不飽和底物（如碳二亞胺，異氰，異硫氰酸鹽，異氰酸酯）反應。其中和R-N=C=N-R (R= TMS, tBu) 反应生成相應的單插入產物。这些单插入产物可以继续和小分子反应插入稀土金屬碳硼烷碳鍵得到双插入产物。並且，這類稀土碳硼烷化合物也可以發生質子化反應生成對應的離子型化合物。 / [Me₃NH][7,8-O(CH₂)₂-7,8-C₂B₉H₁₀]可通過(CH₂OCH₂)C₂B₁₀H₁₀的脫硼反應製備，它與Ln(CH₂-o-C₆H₄-NMe₂)₃ (Ln = Y, Gd, Er, Dy)反應得到半夾心金屬碳硼烷 [η⁵-(CH₂OCH₂)C₂B₉H₉]Ln(CH₂-o-C₆H₄-NMe₂)(THF)₂.不飽和的極性有機不飽合底物可以插入金屬碳鍵，并在取代基的空間位阻效應的影響下生成單插入或者雙插入的產物。 / 該論文中也研究了[η⁵:σ-(C₉H₆)C₂B₁₀H₁₀]Ln[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂和[η⁵-(CH₂OCH₂)C₂B₉H₉]Ln[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂與不同的Brønsted酸的酸堿反應。[η⁵-(CH₂OCH₂)C₂B₉H₉]Y[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂ 同各種各樣的胍反應生成相應的胍基化合物。 / 最後，1-(1-茚基)-1,2-碳硼烷發生脫硼反應可生成對應的[Me₃NH][(C₉H₇)C₂B₉H₁₁]。該配體同Y(CH₂-o-C₆H₄-NMe₂)₃反應得到的稀土烷基化合物[(1-C₉H₆)(C₂B₉H₁₀)]Y(DME)₂也進一步的進行了研究。它同二苯酮，二苯基乙烯酮，二（2-吡啶基）甲酮以及其他不飽和有機化合物反應，得到具有類似結構的單插入產物。 / C,C'-Linked dicarbollide species [Me₃NH][7,8-CH₂OCH₂-7,8-C₂B₉H₁₀] and 1-(1-indenyl)-1,2-carborane were synthesized. Their applications in rare earth chemistry were studied and discussed in this thesis. / 1-(1-Indenyl)-1,2-carborane was synthesized from the reaction of indene epoxide with dilithium salt of carborane. Reaction of this ligand with Ln(CH₂C₆H₄-o-NMe₂)₃ (Ln = Y, Gd, Er, Dy) led to the formation of [η⁵:σ-(C₉H₆)C₂B₁₀H₁₀]Ln[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂ (Ln= Y, Gd, Er, Dy). The metal-carbon σ bond in these complexes was reactive toward unsaturated polar organic substrates, such as carbodiimide, isocyanide, isothiocyanate, and isocynate. They reacted with R-N=C=N-R (R= TMS, tBu) to form mono-insertion products. The metal-cage carbon σ bond in the mono-insertion product was also active toward unsaturated polar organic substrates to form di-insertion complexes. And the indenyl-carboranyl gadolinium complex can be protonated to give ionic species. / [Me₃NH][7,8-CH₂OCH₂-7,8-C₂B₉H₁₀] was prepared by the deboration reaction of (CH₂OCH₂)C₂B₁₀H₁₀. Ln(CH₂C₆H₄-o-NMe₂)₃ (Ln = Y, Gd, Er) reacted with this ligand to form half-sandwich metallacarboranes [η⁵ -(CH₂OCH₂)C₂B₉H₉]Ln[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂. Unsaturated polar organic substrates, such as isocyanide, isothiocyanate, and isocynate can insert into the M-C bond to form mono-insertion complexes or di-insertion complexes depending on the steric factor of the substrate. / Acid-base reactions of [η⁵:σ-(C₉H₆)C₂B₁₀H₁₀]Ln[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂ and [σ:η⁵-O(CH₂)₂C₂B₉H₉]Y[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂ were studied. Complex [σ:η⁵-O(CH₂)₂C₂B₉H₉]Y[σ:σ-(CH₂C₆H₄-o-NMe₂)](THF)₂ reacted with various guanidines to give the corresponding guanidinato products. / Complex [(1-C₉H₆)(C₂B₉H₁₀)]Y(DME)₂ was synthesized and structurally characterized from the reaction of [Me₃NH][(C₉H₇)C₂B₉H₁₁] with Y(CH₂-o-NMe₂-C₆H₄)₃ in DME. Its reactivity was examined. It reacted with diphenylketone, diphenylketene, di(2-pyridyl)ketone and other unsaturated organic compounds to afford mono-insertion products with similar structures. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Yang, Jingying. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 113-124). / Abstracts also in Chinese.

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