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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Synthesis and characterization of new metal complexes with antitumor property

Alrashdi, Salma 01 July 2016 (has links)
Recent studies of new metal complexes for antitumor properties have focused on the speeding up of the treatment process in chemotherapy. In this study, focus was put on the two new metal complexes, copper (LCu(OAc)2) and iron {LFeCl2[FeCl4]}complexes that have been synthesized. Both new complexes have been characterized by FT-IR and UV-Vis. In addition, the structures of two complexes have been established by the X-ray crystallography. The molecular structures of (LCu(OAc)2) and LFeCl2[FeCl4] have been determined confirming that the ligand is bidentate (N,N) imidazopyridine and adopted octahedral configurations. The two complexes and ligand L have been tested for biological activity against prostate cancer cell line LNCaP. The complexes have shown promising results for the anti-proliferative activity. Although the ligand displayed high cytotoxicity toward prostate cancer cell line, the complexes have shown far better cytotoxicity property than the ligand.
272

Synthesis and structural characterization of 2,6-lutidyl bis(thiophosphoranyl) and phosphine (iminophosphoranyl) metal complexes. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Wu, Nip Po. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also Chinese.
273

Synthesis, structural characterization and reactivity of binuclear and polynuclear transition metal complexes containing bridging pyridylphosphine ligands. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Shan-Ming Kuang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (p. 135-152). / 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.
274

Application of Transition Metal Phosphine Complexes in the Modeling of Catalytic Processes: Reactivity with Hydrosilanes and Other Industrially Relevant Substrates

Zuzek, Ashley January 2014 (has links)
The first two chapters of this thesis are devoted to exploring the reactivity of electron rich molybdenum and tungsten trimethylphosphine complexes with hydrosilanes. These complexes, Mo(PMe3)6 and W(PMe3)4(n2-CH2PMe2)H, have been shown to be highly reactive species that undergo a number of bond cleavage reactions. In the presence of the hydrosilanes PhxSiH4-x (x = 0 - 4), Mo(PMe3)6 and W(PMe3)4(n2-CH2PMe2)H effect Si-H and Si-C bond cleavage, along with Si-Si bond formation; however, the products derived from these reactions are drastically different for Mo(PMe3)6 and W(PMe3)4(n2-CH2PMe2)H and are highly dependent on the substitution of the silane. Mo(PMe3)6 reacts with SiH4, PhSiH3, and Ph2SiH2 to afford novel silyl, hypervalent silyl, silane, and disilane complexes, as respectively illustrated by Mo(PMe3)4H2(SiH3)2, Mo(PMe3)4H(k2-H2-H2SiPh2H), Mo(PMe3)3H4(s-HSiHPh2), and Mo(PMe3)3H2(k2-H2-H2Si2Ph4). Mo(PMe3)4H(k2-H2-H2SiPh2H) is the first example of a complex with a hypervalent [H2SiPh2H] ligand, and Mo(PMe3)3H2(k2-H2-H2Si2Ph4) represents the first structurally characterized disilane complex. In addition to being structurally unique, these complexes also possess interesting reactivity. For example, Mo(PMe3)4(SiH3)2H2 undergoes isotope exchange with SiD4, and NMR spectroscopic analysis of the SiHxD4-x isotopologues released indicates that the reaction occurs via a sigma bond metathesis pathway. In contrast, W(PMe3)4(n2-CH2PMe2)H affords a range of products that includes metallacycle, disilyl, silane, and bridging silylene complexes. The disilyl compounds, W(PMe3)4H3(SiH2SiHPh2) and W(PMe3)3H4(SiH2Ph)(SiH2SiHPh2), exhibit the ability of W(PMe3)4(n2-CH2PMe2)H to cause both redistribution and Si-Si bond formation. A mechanism involving silylene intermediates is proposed for the generation of these complexes, and this mechanism is supported computationally. Additional support for the presence of intermediates comes from the isolation of a unique complex with a bridging silylene ligand, "WSiW". The bridging silylene bonding motif is unprecedented. The reactivity of the simplest hydrosilane, SiH4, was also examined with IrCl(CO)(PPh3)2 (i.e. Vaska's compound). Previous reports on this reaction have assigned the product as trans-IrH(SiH3)(Cl)(CO)(PPh3)2, in which the hydride and silyl ligands are mutually trans. It is noteworthy, therefore, that we have now obtained a crystal structure of the product of this reaction in which the hydride and silyl ligands are cis, namely cis-IrH(SiH3)(Cl)(CO)(PPh3)2. Calculated energies of the isomeric species also suggest that the product of this reaction was originally misassigned. These results, and the analogous reactions with germane (GeH4), are described in Chapter 4. Chapter 4 also discusses some reactions of transition metal phosphine complexes, including Ru(PMe3)4H2, Mo(PMe3)6, W(PMe3)4(n2-CH2PMe2)H, and Mo(PMe3)4(n2-CH2PMe2)H, with industrially relevant substrates. Ru(PMe3)4H2 effects the water gas shift reaction of CO and H2O to form CO2 and H2. Furthermore, Ru(PMe3)4H2 reacts with CO2, CS2, and H2S to respectively form formate, thiocarbonate, and hydrosulfido complexes. The reactivity of Mo(PMe3)6 and W(PMe3)4(n2-CH2PMe2)H towards molecules relevant to the hydrodeoxygenation industry, including dihydrofuran and benzofuran, was studied. The products of these reactions exhibit hydrogenation of unsaturated bonds and C-O bond cleavage, both of which are essential to the hydrodeoxygenation process. Mo(PMe3)4(n2-CH2PMe2)H reacts with PhI to form an alkylidyne species, [Mo(PMe3)4(CPMe2Ph)I]I, which was structurally characterized by X-ray diffraction. W(PMe3)4(n2-CH2PMe2)H forms a k2-adduct when treated with 2-seleno-2-methylbenzimidazole, namely W(PMe3)4(sebenzimMe)H. Chapter 3 discusses the development of two new ruthenaboratrane complexes, [k4-B(mimBut)3]Ru(CO)(PR3) (R = Ph, Me). The structures of these complexes are described, and their d6 metal configuration is supported by both Fenske-Hall and Natural Bond Orbital calculations. Some reactivity of these complexes was also explored. For example, [k4-B(mimBut)3]Ru(CO)(PMe3) appears to add MeI across the Ru-B bond. Finally, as an extension of the work that we have done on tungsten trimethylphosphine complexes, the structure of W(PMe3)3H6 in solution was investigated, and the results are presented in Chapter 5. T1 measurements of the hydride ligands and deuterium isotope effect shifts both confirm that this complex exists as a classical hydride in solution, which is in accord with the classical hydride formulation in the solid state that was previously determined by X-ray diffraction.
275

A Journey Across the Periodic Table: The Synthesis and Characterization of Main Group Metals Supported by Nitrogen- or Sulfur-Rich Ligands

Chakrabarti, Neena January 2014 (has links)
In Chapter 1, I discuss the synthesis and characterization of lithium tris(pyrazolyl)hydroborato complexes, [TpR1,R2]Li. Group 1 [TpR1,R2]M complexes serve as key starting points to access many other main group and transition metal complexes; however, the synthesis and crystal structures of [Tp R1,R2]Li has not been reported. Molecular structures of [TpBut]Li and [TpBut,Me]Li show these complexes are trigonal pyramidal, an unusual geometry for lithium. These complexes are also able to bind small molecules to form four-coordinate pseudo-tetrahedral complexes, [Tp]Li-L (L = MeCN, pzButH, and H2O). The binding constants for the association of acetonitrile to [TpBut]Li and [TpBut,Me]Li are 0.84M-1 and 0.96M-1, respectively, indicating that the dissociation of MeCN is facile in solution. In addition, [TpBut,Me]Li serves as transmetallating agent to yield the cadmium halide complexes, [TpBut,Me]CdX (X = Cl, Br, I). In Chapter 2, I discuss the synthesis and characterization of organometallic cadmium complexes supported by the nitrogen-rich multidentate ligands, tris(pyridylthio)methane, [Tptm]H; tris(1-methyl-imidazolylthio)methane, [TitmMe]H; and tris(1-methyl-benzimidazolylthio)methane, [TitmiPrBenz]H. These ligands are in the nascent stages of development and there are only a few metal [Tptm] and [TitmMe] complexes in the literature. An investigation of the reactivity of [L]CdN(SiMe3)2, [L]CdOSiMe3, and [L]CdOSiPh3 ([L] = [Tptm], [TitmMe], [TitmiPrBenz]) shows these complexes provide access to a variety of organometallic cadmium complexes, [L]CdX, (X = OAc, Cl, Br, O2CH, NCO). The characterization of cadmium acetate and formate complexes is significant due to their structural similarity with the metal bicarbonate intermediate formed by zinc and cadmium-substituted carbonic anhydrase. In addition, the synthesis and characterization of cadmium methyl complexes, [L]CdMe, is discussed. The application of heat to a mixture of [TitmiPrBenz]H and CdMe2 results in isomerization of the ligand to [S3-TitmiPrBenz]CdMe. This sulfur-rich [S3-TitmiPrBenz] ligand is not reported in the literature and is ripe for further investigation. The solid state structures of these compounds provide a comparison with biologically relevant [Tp] or [Tm] cadmium methyl complexes in the literature. In Chapter 3, I describe the synthesis and structural characterization of [BmButBenz]M (M = Na, K) and [BmRBenz]Ca(THF)2 (R = Me, But) are discussed. The sulfur-rich tripodal ligand tris(imidazolylthio)hydroborato, [Tm], was previously designed to serve as a softer version of the [Tp] ligand. Metal [Tm] complexes are prevalent in the literature and have often been used as molecular mimics of sulfur-rich enzyme active sites. Recently, the benzannulated [TmRBenz]M complexes were reported and were found to promote k3 coordination toward the metal center. To allow for an in-depth investigation of the newly synthesized [BmRBenz] class of ligand, the [BmButBenz]M (M = Na, K, Ca) complexes were synthesized and compared to previously reported metal [BmMeBenz]M complexes. Additionally, the [BmMeBenz]2Ca(THF)2 was synthesized and characterized via X-ray diffraction. The molecular structure of [BmMeBenz]2Ca(THF)2 shows the complex is monometallic with an uncommon eight-coordinate dodecahedral calcium center. [BmMeBenz]2Ca(THF)2 is the first molecular structure of calcium coordinated to the [Tm] or [Bm] ligand class. In Chapter 4, I discuss the synthesis and characterization of mercury alkyl complexes supported by the [TmMe], [BmR], [TmRBenz] and [BmRBenz] ligands (R = Me or But). As previously mentioned, [Tm]M complexes are considered biologically relevant molecular models of enzyme active sites. With this in mind, [TmBut]HgR (R = Me,Et) complexes have served as mimics for the mercury detoxification enzyme MerB. A previous study by our group showed that the adoption of multiple coordination modes of the ligand in [TmBut]HgR plays a significant role in the activation of the Hg-C bond toward protonolysis. The molecular structures of the [TmR], [BmR], [TmRBenz], and [BmRBenz] mercury alkyl complexes show that they adopt various coordination modes, ranging from k1 to k3. Preliminary competition experiments in which benzenethiol was added to [TmR]HgEt and [TmRBenz]HgEt indicate that the Hg-C bond in [TmMeBenz]HgEt was cleaved faster than that in [TmMe]HgEt. Conversely, the Hg-C bond in [TmBut]HgEt was cleaved faster than that in [TmButBenz]HgEt, indicating that benzannulation and the size of the R-group on the [Tm] ligand play important roles in Hg-C bond cleavage.
276

Synthesis, structure and reactivity of late transition metal and rare earth metal complexes supported by N-anionic ligands. / CUHK electronic theses & dissertations collection

January 2009 (has links)
Chapter 1 gives a brief introduction to metal complexes supported by anionic nitrogen-based ligands. / Chapter 2 describes the synthesis, structural characterization and reactivity of Mn(II), Fe(II) and Co(II) amides derived from the strongly electron-withdrawing [N(C6F5)(C6H3Pr i2-2,6)]- ligand (L 1). Twelve new compounds, including the ligand precursor HL 1, and three alkali-metal and eight late transition metal derivatives of L1, were prepared. Reactions of MCl2 (M = Mn, Fe, Co) with [Li(L1)(TMEDA)] (2) yielded the monoamido complexes [M(L1)Cl(TMEDA)] [M = Mn (5), Fe ( 6), Co (7)]. Treatment of [Li(L1)(THF) 3] with MCl2 (M = Fe, Co) afforded the diamido complexes [M(L1)2(mu-Cl)Li(THF)3] [M = Fe ( 8), Co(9)]. The reaction chemistry of the Co(II) complex 7 was investigated. Treatment of the Co(II) derivative 7 with LiMe, NaN3 and NaOMe gave the corresponding methyl-, azido- and methoxide-amide complexes, namely [Co(L1)(Me)(TMEDA)] ( 10), [Co(L1)(N3)(TMEDA)] (11) and [Co(L1)2(mu-OMe)Na(TMEDA)] (12), respectively. The solid-state structures of complexes 5--12 were determined by X-ray crystallography. / Chapter 3 reports on the synthesis and catalytic properties of lanthanide(III) complexes derived from the unsymmetrical [PhC(NSiMe3)(NC6 H3Pri2-2,6)] - ligand (L2). The lithium and potassium salts of L2, and eight lanthanide(III) derivatives of L2 were synthesized. A series of Ln(III) complexes of the general formula [Ln(L 2)2(mu-Cl)2Li(TMEDA)] [Ln = Y (17), Eu (18), Er (19), Lu (20)] and [Li(THF) 4][Ln(L2)2Cl2] [Ln = Ce ( 21), Nd (22), Sm (23)] were synthesized by the reactions of anhydrous LnCl3 with two molar equivalents of [Li(L2)(TMEDA)] (15). In addition, the neutral dimeric yttrium(III) complex [Y(L2)2(mu-Cl)] 2 (24) was also prepared by the reaction of anhydrous YCl 3 with the potassium amidinate [K(L2)]n (16). The catalytic properties of complexes 20--22 towards the ring-opening polymerization of epsilon-caprolactone were also studied in this work. / Chapter 4 reports on the coordination chemistry of L2 towards divalent lanthanide metal ions. Three neutral divalent lanthanide complexes, [Ln(L2)2(THF)n] [Ln = Sm, n = 2 (25); Ln = Eu, n = 2, (26); Ln = Yb, n = 1 (27)], were prepared by treatment of LnI2(THF) 2 with the potassium amidinate [K(L2)]n . The reaction chemistry of 25--27 as one-electron transfer reagents has been examined. This led to the isolation of six lanthanide(III) complexes (28--33). Treatment of 25--27 with PhEEPh (E = Se, Te) gave the corresponding Ln(III) chalcogenolate complexes [Ln(L2)2(mu-EPh)]2 [Ln = Sm, E = Se (28); Ln = Eu, E = Se (29); Ln = Sm, E = Te ( 31)] and [Yb(L2)2(SePh)(THF)] (30). Besides, the reaction of 27 with iodine resulted in the isolation of the iodide complex [Yb(L2)2(I)(THF)] ( 32), whilst treatment of 25 with dicyclohexylcarbodiimide led to [Sm(L2)2{CyNC(H)NCy}] (33). / Chapter 5 summarizes the results of this research work. A brief suggestion on future directions of this research project is also discussed. / The present research work was focused on the coordination chemistry of the highly electron-withdrawing [N(C6F5)(C6H 3Pri2-2,6)]- ligand and the unsymmetrical [PhC(NSiMe3)(NC6H 3Pri2-2,6)- ligand. The first part of this work was centered on the synthesis, structure and reactivity of late transition metal complexes supported by the [N(C6F5)(C6H3Pr i2-2,6)]- ligand (L 1). The second part of this work dealed with the chemistry of trivalent and divalent lanthanide complexes derived from the bulky [PhC(NSiMe3 )(NC6H3Pri 2-2,6)]- ligand (L2). / Yao, Shuang. / Adviser: Hung Kay Lee. / Source: Dissertation Abstracts International, Volume: 71-01, Section: B, page: 0317. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.
277

Transition metal complexes of X-bridged nitrogen heterocycles (X represents C=O, S=O, or O=S=O). / 羰基、亚砜及砜官能团桥联氮杂环配体的过度金属化合物的研究 / CUHK electronic theses & dissertations collection / Tang ji, ya feng ji feng guan neng tuan qiao lian dan za huan pei ti de guo du jin shu hua he wu de yan jiu

January 2008 (has links)
2-Pyridinyl-2-pyrazinylmethanone (L4) is able to exist in the neat ketone form and gem-diol form (2-C5H4N)C(OH) 2(2-C4H3N2) (L4a) in its Ag(I) and Cu(II) complexes. Two isostructural Cu(II) complexes [Cu(L4 a)2X2·2H2O, X = C lO4-, BF4-] with the L4a ligand taking the chelating mode are formed, in which the different linkage modes of lattice water molecules between the Cu(L4 a)22+ units lead to different space groups in crystallization. Through versatile anion-pi(pyrazinyl ring) and hydrogen-bonding interactions, the Cu(L4a)22+ units are assembled into distinct 3-D metal-organic hybrid frameworks in these two complexes. Different ligation modes of L4 in its neat ketone and gem-diol forms are found in its silver(I) complexes that exhibit diverse network structures. / By tuning the counter anion, mu2-bridging 2,6-pyridinediylbis(4-pyridinyl)methanone (L2) via two terminal 4-pyridyl N atoms links Ag(I) ions into two distinct structural motifs in its silver(I) complexes, namely infinite helical chain and metallacyclophane, which are further assembled into higher-dimensional metal-organic frameworks through Ag···Ag, pi···pi, hydrogen-bonding, Ag···O=C, carbonyl···carbonyl, as well as unconventional anion-pi(pyridyl ring) interactions. Intermolecular dipolar carbonyl···carbonyl interaction of three principal types serves as a common dominant non-covalent interaction in the supramolecular conglomeration of these complexes. / Di-2-pyrazinylmethanone (L3) readily undergoes metal-assisted hydration reaction in its Ag(I), Cu(II), Co(II) and Cd(II) complexes, and is potentially useful for the construction of extended coordination networks with its gem-diol (2-C4H3N2)2C(OH) 2 (L3a) or anionic (2-C4H3N 2)2C(OH)CO- (L3b) form as an architectural moiety. A sheet-like net, an alpha-polonium topology of the NaCl-type and a rare 1-D nanotubular coordination architecture has been generated in its Ag(I) complexes through the tuning of counter-anions. Three isostructural complexes Cu(L3a)2X2· nH2O (n = 4.5; X = ClO 4-, BF4-, PF 6-) have been obtained and characterized. The 3-D host frameworks of these complexes are constructed from the linkage of mononuclear Cu(L3a)22+ metallotectons through a combination of hydrogen-bonding and anion-pi interactions, leading to honeycomb-like channels that accommodate guest water molecules. A cubane-like Co(II) cluster stabilized by L3b and the topological structure of Cd(II) complexes with L3a have also been obtained. / Di-2-pyridinylmethanone (di-2-pyridyl ketone) is a well-known versatile ligand among the basic building blocks for the construction of metal-organic hybrid materials. It can exist in its neat form, or in the hydrated gem-diol and alcoholated hemiketal forms. In this thesis, through modification of the heterocyclic ring and the bridging functional group, we have systematically synthesized a series of transition metal complexes of five carbonyl-bridged heterocycles (L1-L5) (see P. xi) and two structural analogs with sulfinyl and sulfonyl bridging groups (L6-L7), which are expected to provide flexible coordination bonding and additional non-covalent interactions in the generation of metal-organic hybrid frameworks. / In the two mononuclear Cu(II) complexes of 2,6-pyridinediylbis(3-pyridinyl)methanone (L1) with the ligand taking a chelating mode, four distinct types of unconventional intermolecular C=O···pi interactions between the carbonyl and pyridyl rings were identified. Moreover, the mu2-bridging L1 via two 3-pyridyl N atoms proves to be an excellent building block for the construction of disilver(I) metallacyclophanes with a [Ag2(L1) 2]2+ skeleton in a series silver(I) complexes. The [Ag 2(L1)2]2+ metallacycle functions as a secondary building unit to form infinite chains through Ag···O=C or argentophilic interactions, which are further assembled into a 3-D supramolecular structure via collective weak interactions including the anion-pi interaction. The employment of different Cd(II) and Hg(II) salts to react with the flexible L1 ligand has resulted in infinite chain, mononuclear, and 3-D network structures, in which L1 takes eta1-terminal, N,N-chelating, and mu2- and mu3-bridging modes. In these complexes, C--H···O, C--H···Cl--M hydrogen bonding, pi···pi, carbonyl···carbonyl, O(perchlorate)···C=O, as well as unconventional anion···pi(pyridyl ring) interactions, play important roles in consolidation of the supramolecular frameworks. / Sulfinyldipyrazine (L7) is capable of forming intriguing architectures in various sivler(I) salts, including a series of coordination polymers exhibiting (4,4) net, infinite chain and 3-D framework structures. A remarkable characteristic of L7 is that the electron-deficient pyrazinyl ring and the sulfonyl group provide potential bonding sites for lone-pair-aromatic interactions in the supramolecular assemblies, such as anion-pi and S=O···pi(pyrazinyl ring) interactions. The S=O moiety of the sulfonyl group exhibits an affinity for the pyrazinyl ring, which is evidenced by the existence of two types of such interaction in the silver(I) complexes of L7. (Abstract shortened by UMI.) / by Wan, Chongqing. / Adviser: Thomas C. W. Mak. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3504. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 172-190). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
278

Late transition metal-carboryne complexes and their reactions with alkenes and alkynes. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Abstract not available. / Qiu, Zaozao. / Adviser: Zuowes Xie. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 150-161). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
279

The chemistry of bisgermavinylidene, bis-(iminophosphorano)methanide tin(II) chloride and group 14 metal bis(thiophosphinoyl) complexes. / CUHK electronic theses & dissertations collection

January 2007 (has links)
Chapter 1 describes the reactivities of bisgermavinylidene [(Me 3SiN=RPh2)2C=Ge→Ge=C(PPh2=NSiMe 3)2] (25). With the use of CpMnCO2(THF), Mn2(CO)10 and group 11 metal halides, manganese-germavinylidene complexes and germavinylidyl group 11 metal complexes were prepared respectively. Radical reaction of 25 with 2,2,6,6-tetramethylpiperidine N-oxide affords [(Me3SiN=RPh2)2C=Ge(ONCMe2C 3H6CMe2)2] (40). Cycloadditon reactions of 25 were studied. The reaction of 25 with benzil, azobenzene or 3,5-di-tert-butyl-o-benzoquinone affords [(Me3SiN=PPh2)2C=Ge{O(Ph)C=C(Ph)O}] (41), [(Me3SiN=PPh2)2C=Ge( o-C6H4NHNPh)](42) and [(Me 3SiN=PPh2)2C=Ge=C-(PPh2=NSiMe 3)2] (44), respectively. The C=Ge bond of 25 can undergo cycloaddition reactions with Me3SiN 3, Me3SiCHN2 or AdNCO (Ad = adamantly) to give [(Me3SiN=PPh2)2CGeN(SiMe3)N=N] (46), [(Me3SiN=PPh2)2C-GeN=NCH-SiMe 3] (48) and [(Me3SiN=PPh2)2 CGeN(Ad)C-O] (47), respectively. Furthermore, 1,2-addition products of rhodium(I) and tin(IV) complexes were prepared from the reaction of 25 with (cod)RhCl and (nBu) 3SnN3, respectively. The syntheses of bimetallic chlorides [(Me3SiN=PPh2)2(GcCl)CMn(mu-Cl)]2 (51) and [(Me3SiN=PPh2)2(GeCl)CFeCl] (52) are also reported. / Chapter 2 concerns the reactivities of bis(iminophosphorano)methanide tin(II) chloride [HC(PPh2=NSiMe3)2SnCl] ( 79). The reactivity of the lone pair in 79 was studied. The reaction of 79 with benzil or 3,5-di-tert-butyl- o-benzoquinone gives the corresponding cycloaddition products. Treatment of 79 with NaN3 or AgOSO2CF3 affords the corresponding substituted heteroleptic stannylenes. The reaction of 79 with W(CO)5THF gives an adduct [HC(PPh 2=NSiMe3)2(Cl)Sn→W(CO)5] ( 81). Compound 79 reacts with Fe{N(SiMe3) 2}2 to afford [HC(PPh2=NSiMe3) 2Fe(mu-Cl)]2 (86). Moreover, treatment of 79 with LiC≡CPh gives [HC(PPh2=NSiMe3) 2C(Sn)=C(Ph)Sn(C≡CPh)2]2 (87). / Chapter 3 deals with the preparation and characterization of group 14 bis(thiophosphinoyl) metal complexes. The newly developed ligand [(S=PPr i2CH2)2-C5H 3N-2,6] (126) undergoes metalation with nBuLi or (nBu)2Mg to afford the lithium complex [Li{(S=PPri 2CH)(S=PPi2CH2)C 5H3N-2,6}(Et2O)] (127) and magnesium complex [Mg(S=PPri2CH)2C 5H3N-2,6] (128), respectively. 1,3-Distannylcyclobutane and 1,3-diplumbacyclobutane were prepared from treatment of 126 with M{N(SiMe3)2}2 (M Sn, Pb) by the amine-elimination reaction. Furthermore, compound 127 reacts with GeCl2.dioxane or SnCl2 to afford digermylgermylene Ge[GeCl2{(S=PPr i2CH)(S=PPri 2CH2)C5H3N-2,6}]2 ( 131) and ionic tin(II) complex [{C5H3N-2,6-(CH 2PPri2=S)(CHPPr i2=S)}SN+][SnCl3 -] (134), respectively. / Chapter 4 describes the conclusion of the first three chapters. The future works of the first three chapters were also reported. / This thesis is focused on four areas: (i) the reactivities of bisgermavinylidene; (ii) the reactivities of bis(iminophosphorano)methanide tin(II) chloride; (iii) the synthesis of group 14 bis(thiophosphinoyl) metal complexes and (iv) conclusions and future works. / Kan, Kwok Wai. / "Aug 2007." / Adviser: Kevin W. P. Leung. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 1007. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.
280

Syntheses, structures and reactivities of metal complexes containing tridentate pyridyl-linked dianionic ligands. / Synthesis, structures and reactivities of metal complexes containing tridentate pyridyl-linked dianionic ligands / CUHK electronic theses & dissertations collection

January 2002 (has links)
"January 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / 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.

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