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Dissertations / Theses on the topic 'Bulky Ligands'

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Published: 4 June 2021

Last updated: 14 February 2022

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1

Prabagar, Jasotha. "Synthesis of bulky phosphine ligands." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437012.

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2

Jones, Claire Frances. "Lanthanide complexes of bulky hybrid ligands." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/4009.

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The synthetic and redox chemistry of lanthanide organometallic complexes has considerably expanded since the discovery of Kagan’s reagent in 1977 and divalent ionic complexes are now known for the entire lanthanide series. The synthesis, solid-state structures and reductive chemistry of trivalent and divalent lanthanide complexes with cyclopentadienyl-type ligands is reviewed with a focus on the impact of the ligand on the reducing power of the metal centre. Trimethylsilyl and more recently, phosphine-borane stabilised carbanions have facilitated the isolation of trivalent and divalent lanthanide complexes of alkyl ligands with Ln—C σ-bonds. The synthesis, structures and known reactivity of these compounds is discussed. In order to probe the impact of alkyl carbanion and cyclopentadienyl coordination on lanthanide complex stability, structure and redox reactivity we have designed a novel set of hybrid ligands that combine these two functional groups into a single dianionic ligand. These ligands are potentially very versatile as the sterics and electronics of both groups in the ligand can be modified. The ligands are viable to support sterically congested trivalent complexes for sterically induced reduction as well as metal based reduction and they are good ligands for heteroleptic complexes because they chelate the metal avoiding ligand redistribution equilibria. The synthesis and characterisation of a range of trimethylsilyl-, phosphine-borane- and phosphine-stabilised alkyl bromo- and chlorosilane precursors is described: (Me3Si)2CHSiMe2Br [4], (Me3Si){PMe2(BH3)}CHSiMe2Cl [9], (Me3Si){PnPr2(BH3)}CHSiMe2Cl [13], {PMe2(BH3)}2CHSiMe2Cl [23], {PMe2(BH3)}{PPh2(BH3)}CHSiMe2Cl [27], {PPh2(BH3)}2CHSiMe2Cl [31] and (nPr2P)2CHSiMe2Cl [32]. iv The results of a computational study using NBO methods to investigate the relative stabilising effect of each of these silyl, phosphine-borane and phosphine carbanion stabilising groups on a model system akin to the alkyl part of the hybrid ligand are described. Reaction of (Me3Si)2CHSiMe2Br with Li/Na/K Cp/Cp’/Cp4Me followed by aqueous work-up gave the hybrid proligands {(CpH)Me2Si}(Me3Si)2CH [5], {(Cp’H)Me2Si}(Me3Si)2CH [6] and {Cp4MeH)Me2Si}(Me3Si)2CH [7] as mixtures of regioisomers [Cp4Me = 1,2,3,4-Tetramethyl-cyclopentadiene]. Reaction of LiCp4Me/KCp4Me with (Me3Si){PMe2(BH3)}CHSiMe2Cl and (Me3Si){PnPr2(BH3)}CHSiMe2Cl gave the hybrid proligands (CpH4MeMe2Si)(Me3Si)CH{PMe2(BH3)} [10] and (CpH4MeMe2Si)(Me3Si)- CH{PnPr2(BH3)} [14]. The compounds {Cp4MeH)Me2Si}(Me3Si)2CH, (CpH4MeMe2Si)- (Me3Si)CH{PMe2(BH3)} and (CpH4MeMe2Si)(Me3Si)CH{PnPr2(BH3)} crystallise as solvent-free monomers with very similar molecular conformations. The hybrid pro-ligands exhibit variable moisture sensitivity. Reaction of (Me3Si){PMe2(BH3)}CHSiMe2Cl with NaCp followed by aqueous work-up and column chromatography of the oily residue obtained gave the siloxane [(Me3Si){PMe2(BH3)}HCMe2Si]2O [19] and dicyclopentadiene. Reaction of (nPr2P)2CHSiMe2Cl with NaCp followed by aqueous work-up using deoxygenated water gave (nPr2P)2CH2 in quantitative yield. The same reaction avoiding the aqueous work-up gave (CpHMe2Si)CH(PnPr2)2 [33]. Hybrid ligands were prepared by metalation of {Cp4MeH)Me2Si}(Me3Si)2CH, {(Cp’H)Me2Si}(Me3Si)2CH and {(CpH)Me2Si}(Me3Si)2CH with MeK to give the hemisolvated dipotassium salts [(CpMe2Si)(Me3Si)2C]K2(Et2O)0.5 [50], [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O)0.5 [51] and [(Cp’Me2Si)(Me3Si)2C]K2(C6H6)0.5 [52], which decomposed slowly in THF and toluene. [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O) [51.Et2O] was crystallised as an alternative solvate from diethyl ether and the v extended structure consists of chelated [(hybrid ligand)K(Et2O)]- anionic units linked nose to tail by unsolvated K cations in a non-linear (zig-zag) polymer chain. [(Cp’Me2Si)(Me3Si)2C]K2(C6H6)·C6H6 [52.C6H6] also crystallised as a monosolvate from benzene, but with addition uncoordinated solvent present in the structure. There are two distinct types of polymer chain in the structure of [(Cp’Me2Si)(Me3Si)2C]K2(C6H6)·C6H6, one is similar to the chain in [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O) and in the other half the potassium cations in this chain are coordinated by only a cyclopentadienyl ring and a benzene ring. The remainder of the K cations are sandwiched between a carbanion and cyclopentadienyl ring of different hybrid ligands, as in [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O). These chains are cross-linked by a short contact between K and the –SiMe3 substituent of the Cp’ ring. Due to their more acidic alkyl protons metalation of (CpH4MeMe2Si)(Me3Si)CH{PMe2(BH3)}, (CpH4MeMe2Si)(Me3Si)CH{PnPr2(BH3)} and (CpHMe2Si)CH(PnPr2)2 could be achieved with BnK in THF. (CpH4MeMe2Si)(Me3Si)CH{PMe2(BH3)} is isoelectronic and isosteric with {Cp4MeH)Me2Si}(Me3Si)2CH. [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]K2(THF) [53.THF] crystallises as a solvate from benzene/THF with a 3D polymeric network structure through multiple agostic-type B—H····K contacts. Of the two symmetry inequivalent K cations in the structure the alkyl carbanion interacts directly only with the unsolvated cations and the solvated cations are coordinated through the borane-hydrogens. Metathesis reactions of [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O)0.5 and [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]K2(THF)0.5 with LaI3(THF) and SmI3(THF) in THF gave [(Cp4MeMe2Si)(Me3Si)2C]LaI(THF)2 [56] and [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]-SmI(THF)2 [57] after extraction into diethyl ether and crystallisation from toluene/THF and diethyl ether respectively. The vi hybrid ligand bound successfully to the lanthanide metal cations. [(Cp4MeMe2Si)(Me3Si)2C]LaI(THF)2 is a monomer in the solid-state, chelated by the hybrid ligand forming pseudo-four-membered ring and two coordinating molecules of THF in addition to the iodine anion. A zwitterion structure is adopted by [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]SmI(THF)3 with no contact between the Sm(III) cation and the alkyl carbanion centre. The hybrid ligands have a much larger cone angle and are far more sterically bulky when chelating the lanthanide metal, as in [(Cp4MeMe2Si)(Me3Si)2C]LaI(THF)2. The metathesis reaction of [(Cp4MeMe2Si)(Me3Si)2C]K2(Et2O)0.5 with CaI2 gave [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]Ca(THF)2 [58] after extraction and crystallisation from diethyl ether. In this structure the phosphine-borane stabilised carbanion group of the hybrid ligand coordinates the Ca cation through the carbanion centre. Synthesis of the Yb(II) analogue, [(Cp4MeMe2Si)(Me3Si){PMe2(BH3)}C]Yb(THF)x gave an almost identical NMR spectrum, but could not be crystallised.

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3

Frew, Jamie J. R. "Novel bulky fluorinated ligands for homogeneous catalysis." Thesis, University of St Andrews, 2008. http://hdl.handle.net/10023/852.

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A series of novel monodentate and bidentate phosphine ligands substituted with bulky tert-butyl and fluorinated aryl groups have been synthesised. Borane protection has proved to be an excellent method for easy synthesis and purification of bidentate ligands in some cases. However, several of the bulky fluorinated ligands do not form stable borane complexes leading to complications in the synthesis and purification of these compounds. By reaction with transition metal platinum and palladium precursors, it was possible to form dichloride complexes from the synthesised ligands, which were characterised by X-ray crystallography. The complexes were found to be effective catalysts for the hydroxycarbonylation of vinyl arenes (yields of up to 95 % with 3 mol% catalyst). An unsymmetrical bidentate complex (3.18) in combination with paratoluenesulfonic acid and LiCl promoters has given exceptional (for a diphosphine ligand) regioselectivity for the branched acid (98.7 % branched) in the hydroxycarbonylation of styrene. The role of the promoters has been found to be crucial in deciding the activity and selectivity in this reaction.

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4

SoÌˆezerli, Sebnem Esen. "Organometallic compounds with bulky silyl-substituted ligands." Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388678.

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5

Slot, Saskia Carolien van der. "Rhodium-catalysed hydroformylation using bulky phosphorus diamide ligands." [S.l : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2001. http://dare.uva.nl/document/60662.

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6

Graham, A. "Binuclear and polynuclear metal complexes with bulky ligands." Thesis, University of Edinburgh, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.651687.

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This thesis presents routes to transition metal complexes of pyridonate and carboxylate ligands. Low nuclearity complexes with triphenyl acetate and 1<sup>st </sup>row transition metals of the formula [M<sub>4</sub>(OMe)<sub>4</sub>(O<sub>2</sub>CCPh<sub>3</sub>)<sub>4</sub>(MeOH)<sub>4</sub>] (M = Co, Ni or Zn) have been synthesised and mark a change from reactions with other carboxylates which produce linear trinuclear complexes. Molecular modelling studies investigate the close contacts that arise if triphenyl acetate is incorporated into a linear trinuclear compound to establish whether steric interactions are controlling reactivity. High nuclearity complexes with cobalt and nickel have been, made, many of which extend the range of complexes in which the metal atoms form a centred tricapped trigonal prism. These complexes all contain [M<sub>10</sub>(OH)<sub>6</sub>(O<sub>2</sub>CCPh<sub>3</sub>)<sub>6</sub>(xhp)<sub>6</sub>]<sup>2+</sup> (xhp = a pyridone anion substituted at the six position) core with metal atoms capping the triangular faces of the centred prism. A variant on previous trapped trigonal prisms is also presented, in which the cap metal atoms cap the prism edges. In other complexes the metal atoms form new topologies, ranging from hexa- to octanuclear. In some complexes sodium atoms are also incorporated into the polynuclear cages. Reaction conditions for formation of these cages was investigated. Variation of the metal salt from chloride to nitrate influences both the yield of high nuclearity complexes and the timescale over which they are formed. The choice of recrystallisation solvent affects the cage formed. For example. hexanuclear and heterometallic octanuclear cobalt complexes follow identical syntheses except for the recrystallisation solvent. The means by which counterion and recrystallisation solvent influence reactivity is unclear.

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7

Graham, Alasdair. "Dinuclear and polynuclear metal complexes with bulky ligands." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/12051.

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8

Hawkes, Simon Anthony. "Main-group organometallic compounds with bulky silyl-substituted allyl ligands." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285104.

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9

Pugh, Robert Ian. "Phospha-adamantanes : a new class of bulky alkyl phosphine ligands." Thesis, University of Bristol, 2000. http://hdl.handle.net/1983/45a5eb1f-2213-49d6-a041-f5e597fa3469.

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10

Hopman, Martyn. "Organometallic compounds with bulky, phenyl-substituted, or derived donor-substituted ligands." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285105.

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11

Doran, Seán. "The synthesis and application of bulky S-stereogenic and P- stereogenic chiral ligands." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/96997.

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This doctoral thesis was focused on the design and synthesis of novel chiral ligands for application in asymmetric catalysis. One of the best examples of asymmetric catalysis is the asymmetric hydrogenation reaction for its atom economy, ease of access to both S and R enantiomers and almost ultimate enantiomeric excess obtainable in a multitude of substrates. There has been much investigation into this reaction and there has been a plethora of chiral ligands designed which catalyze this reaction in high enantiomeric excess using metals such as rhodium, iridium and ruthenium. The vast majority of these ligands are diphosphines with their chirality lying either on the backbone of the ligand or on the coordinating phosphorus atom itself. In the beginning of this work investigation was undertook to explore the possibility of successfully employing a new type of ligand class in the asymmetric hydrogenation reaction, namely the N-phosphino sulfinamide or PNSO ligands. PNSO ligands had been successfully applied to the asymmetric Pauson-Khand reaction in the Riera group yielding cyclopentenone Pauson-Khand adducts in high yield and very high enantioselectivity. The family of PNSO ligands prepared in the Riera group was attractive because apart from the high yields and enantioselectivities obtained from the reactions in which they were used, they proved to be easily prepared in short syntheses from commercially available starting materials. It was believed if they could be successfully applied in asymmetric hydrogenation for their ease of preparation they would be an attractive alternative to the diphosphine ligand class. Unfortunately the first two PNSO-Rh complexes successfully prepared provided low enantioselectivities and difficulties were encountered while trying to prepare further analogues. After some time trying to achieve PNSO-Rh complex analogues unsuccessfully the direction of the project was shifted away from the N-phosphino sulfinamide ligand class in asymmetric hydrogenation. The MaxPhos ligand had recently been developed in the group and had proven highly promising. A study was demanded of its substrate scope as applied in rhodium catalyzed asymmetric hydrogenation. Substrates already described in the literature were prepared and the asymmetric hydrogenation of them catalyzed by the MaxPhos-Rh precatalyst was performed and conditions to do so were optimized. Of seven substrates prepared the MaxPhos-Rh proved to hydrogenate five of those with high enantioselectivity. The TOF of the MaxPhos rhodium catalyst applied in the hydrogenation of the Z-MAC substrate was examined by monitoring the flux of hydrogen and was calculated at 0.065 s-1. MaxPhos complexes of cobalt and palladium were prepared to form part of the investigation into widening the reaction scope of the ligand. [(MaxPhos)Co2(CO)4(C2H2)] proved to catalyze the Pauson-Khand reaction of norbornadiene and 1-hexyne with 24 % yield and 28 %, a noteworthy enantiomeric excess for the catalytic asymmetric Pauson-Khand reaction. Chalcogenated derivatives of MaxPhos were prepared. The diselenide was used to explore the electronic nature of the ligand. The MaxPhos-rhodium carbonyl stretching was examined. MaxPhos-BH3 was used to prepare mono-chalcogenated MaxPhos derivatives. They were applied also in asymmetric hydrogenation once complexed to rhodium but enantiomeric excess of no more than 21 % was obtained in the hydrogenation of the substrate Z-MAC. The aminophosphine, a chiral building block and key intermediate in the preparation of the MaxPhos ligand, was used in the attempt to prepare bulky chiral amidine ligands and although two such species were prepared they proved inapplicable in asymmetric catalysis.<br>Se desarrollaron los ligandos N-fosfino sulfinamida (PNSO) en el grupo de Riera para su aplicación en la reacción Pauson-Khand asimétrica. Se probaron que estos ligandos eran muy eficaces en esta reacción y daban rendimientos y enantioselectividades muy altos de los aductos Pauson-Khand. Probar la eficacia de estos ligandos PNSO en hidrogenación asimétrica formó parte de este trabajo. Se prepararon dos ligandos PNSO, se complejaron con rodio formando complejos neutros. Se protonaron los complejos neutros con ácido tetraflorobórico para formar los complejos catiónicos. Se usaron estos complejos de rodio- PNSO, tanto los complejos neutros como los catiónicos como catalizadores en la hidrogenación asimétrica del sustrato Z-MAC. Los complejos de rodio con el ligando PNSO substituido por el grupo tolilo en azufre no hidrogenaba el sustrato pero los complejos de rodio con el ligando PNSO dotado de tres grupos tert-butilos hidrogenaba el sustrato aunque con baja selectividad. Después de un tiempo intentando conseguir análogos de ligandos tipo PNSO sin éxito se cambió la dirección del proyecto. Se decidió centrarse en el ligando MaxPHOS el cual había sido desarrollado recientemente en el grupo Riera. El ligando MaxPHOS demostró gran eficacia en hidrogenación asimétrica con dos sustratos pero se deseaba un estudio mas amplio del potencial del ligando así que se sintetizaron siete sustratos y se probó el catalizador MaxPHOS en la hidrogenación asimétricas de esos sustratos. El catalizador MaxPHOS-Rh proporcionó excesos enantioméricos muy altos en cinco de los siete sustratos. Se hizo un estudio de las propiedades electrónicas del ligando MaxPHOS aprovechando los estudios de (31)P RMN y el MaxPHOS diselenuro lo cual se preparó anteriormente. También se estudió el “stretching” carbonilo del complejo MaxPHOS-Rh. Se demostró que el ligando MaxPHOS era menos rico en electronos que el ligando trichickenfootphos. Se prepararon complejos de MaxPHOS con paladio y cobalto para examinar la eficacia del ligando en reacciones mas allá de hidrogenación asimétrica como la reacción Pauson–Khand catalítica asimétrica. Se sintetizaron varios derivados del ligando MaxPHOS a partir de los intermedios clave en la preparación del ligando y se probaron en hidrogenación asimétrica proporcionando excesos enantioméricos bajos.

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12

Cornet, Stephanie Michele Marie. "Synthesis and characterisation of some main-group compounds with bulky electron-withdrawing substituents." Thesis, Durham University, 2002. http://etheses.dur.ac.uk/4173/.

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Several new group 13, 14 and 15 derivatives with the ligands 2,4,6-(CF(_3))(_3)C(_6)H(_2) (Ar), 2,6- (CF(_3))(_2)C(_6)H(_3) (Ar') and / or 2,4-(CF(_3))(_2)C(_6)H(_3) (Ar") have been prepared. They have been characterised by multinuclear NMR spectroscopy and, for all isolated compounds, by elemental analysis and, where possible, single crystal X-ray diffraction. Reaction of ArLi or the mixture Ar'Li/Ar"Li with BCI3 has led to the characterisation of several mono- and disubstituted compounds, but attempted substitution in AICI3 was unsuccessful. Reaction of EC1(_4) (E = Si, Ge, Sn) with the Ar'Li/Ar"Li mixture yielded predominantly the less sterically hindered disubstituted product Ar"(_2)ECl(_2) for E = Si and Ge but to Ar'(_2)ECl(_2) for E = Sn. In the case of B or Si, chlorine exchange is observed and Ar(_2)BF, Ar(_2)SiF(_2) and Ar'(_2)SiF(_2) have been synthesised. Ar(_2)SiF(_2) is the only product identified in the reaction of ArLi with SiC1(_4). Reaction of ArLi or the Ar'Li/Ar"Li mixture, in an appropriate ratio, with group 15 derivatives gave rise to several mono-or disubstituted compounds of the type ArEX(_2), Ar(_2)EX, Ar'EX(_2), Ar"EX(_2), Ar"(_2)EX and Ar'Ar"EX (E = P or As; X = H, CI or Br). (^19)F NMR spectra of Ar'Ar"EX show that, for the two ortho-CF(_3) groups of the Ar' moiety, there is free rotation of the aryl group around the central atom. A series of variable temperature studies has been carried out, and allowed the determination of the rotational energy barrier of the molecule. For the first time, the molecular structures of derivatives containing three fluoroxyl ligands have been determined (Ar"(_3)B and Ar'Ar"(_2)Sb).The synthesis of some new platinum complexes has been facilitated by reaction of phosphanes with the platinum dimer [(PtCl(_2)(Pet(_3))](_2) or [(PtBr(_2)(Pet(_3))](_2). Reactions of the platinum dimer with arsane derivatives have not been successful. Halogen exchange was observed between bromophosphane ligands and CI groups on the platinum. Attempts have been made to synthesise new P=E derivatives containing the electron- withdrawing substituents Ar or Ar' via reaction with the chlorine abstractor W(PMe(_3))(_6)- ArP=PAr and Ar'P=PAr' have been prepared. Synthesis of the first phosphaalkyne containing Ar or Ar' has been attempted by reacting a phosphaalkene with a Pt(0) species.

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13

Taguchi, Hiroomi. "Studies on PNP-Pincer Type Phosphaalkene Complexes Stabilized by a Fused-Ring Bulky Protection Group." Kyoto University, 2018. http://hdl.handle.net/2433/232481.

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14

Zhu, Hongping. "The Reaction Chemistry of Aluminum(I,III) Compounds Stabilized by Sterically Bulky Ligands." Doctoral thesis, [S.l.] : [s.n.], 2005. http://webdoc.sub.gwdg.de/diss/2005/zhu.

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15

Köhne, Ingo. "Novel Bulky Bis(benzoxazol-2-yl)methane Ligands in s-Block Metal Coordination." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E3E8-1.

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16

Chao, Hsiu-Yi. "Luminescent organogold(I) complexes with electron rich bulky phosphine ligands : synthesis and spectroscopic studies /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?23242309.

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17

趙修毅 and Hsiu-Yi Chao. "Luminescent organogold(I) complexes with electron rich bulky phosphineligands: synthesis and spectroscopicstudies." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31241499.

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18

Espana, Raquel Gracia. "Structural, electronic and catalytic studies of diruthenium and diosmium paddlewheels with bulky carboxylate ligands." Thesis, University of Sheffield, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556689.

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A senes of RU2(II,III) complexes containing the bulky carboxylate ligand 2,4,6- triisopropylbenzoate (TiPB) of form trans-[Ru2(TiPB)2(02CCH3)2X] [X = Cl 1, PF6 2] and [Ru2(TiPB)4X] [X = Cl 3, PF6 4] have been synthesised. The corresponding RU2(II,II) complexes trans-[Ru2(TiPB)2(02CCH3)2] 5 and [Ru2(TiPB)4] 6 were also isolated. The Ru-Ru bond length in the RU2(II,II) complex 6 [2.2425(6) A] is the shortest observed for a diruthenium tetracarboxylate and, surprisingly, is 0.014 A shorter than in the analogous RU2(II,III) complex 4, despite an increase in the formal bond order from 2.0 in the RU2(II,II) complex 6 to 2.5 in the RU2(II,III) complex 4. This is rationalised in terms of the extent of internal rotation about the RU2 core. This was supported by DFT calculations on the model complexes [RU2(02CH)4]OI+, that demonstrate the relationship between Ru-Ru bond length and internal rotation. The mixed carboxylate complexes trans-[Ru2(02CCH3)2(02CAr)2Cl] 7 and trans[ RU2(02CCH3)2(02CAr)2] 11 (02CAr 2,6-di(p-tolyl)benzoate) have been synthesised along with [Ru2(02CAr)4(CH2Cb)Cl] 9 and [RU2(02CAr)4] 12 complexes. The structure of 9 is a rare example of a structurally characterised dichloromethane complex. The bulky -02CAr ligand protects the axial positions from intermolecular interactions in the absence of strong nuc1eophiles for 9 and 12, and the effect this has on the electronic structure of the diruthenium core in these complexes was investigated. Complexes [RU2(,l1-0)2CU-TiPB)2(TiPB)2] and [RU2(,l1- OMe )2(,l1-TiPB)2(TiPB)2] were structurally characterised using crystals obtained from decomposition of [Ru2(TiPB)4] solutions. [RU2 TiPB)4] is capable of activating dioxygen, and can act as a biologically-inspired catalyst for the aerobic oxidation of alcohols to aldehydes. The synthesis of the diosmium tetracarboxylates [Os2(TiPB)4Cb] 15 and [Os2(TiPB)2(02CCH3)2Cb] 16 is also reported and the electronic structure of these complexes is probed with the aid of DFT calculations.

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19

Megrahi, Abdunnaser. "Super bulky α-diimine ligands and their coordination complexes for use as polymerization catalysts". Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505376.

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The TiCl4 mediated condensation of benzil with anilines followed by Li mediated cyclodehydrogenation of the resulting benzildiimines to access the superbulky a-dimine ligands Ll (N,N'-bis-(2,6-diisopropylphenyl)-phenanthrene-9, 1 O-diylidendiamine) and L2 (N-(2,6- diisopropylphenyl)-N'-(2,4,6-trimethylphenyl)-phenanthrene-9, 1 O-diylidenediamine) is described in this work. This route has been chosen among many other routes which failed to access these ligands. These ligands have been for the first time synthesized and fully characterized, including their single crystal X-ray structures. Attempts to tetrahedrally coordinate NiBr2 to the super bulky ligand Ll failed due to the axial crowding caused by the aryl substituents in the ortho position. Reducing this axial bulk at one side of the ligand from isopropyl groups to methyl groups as in ligand L2 enabled the synthesis of the tetrahedral NiBr2-complex (L2NiBr2). A failure has been also the attempt to coordinate MO(CO)4 to both these ligands. Instead, with the super bulky ligand Ll, a square planar Ni-allyl complex [(113- LINiC3~COOCH3)t. {B[C6H3(CF3)2k} could be easily accessed. These Ni-complexes have shown to be potent catalysts for ethylene polymerisation. The Ni-allyl version of ligand Ll has not been able to polymerize I-hexene. PdCh complexes (LIPdCh) and (L2PdCh) have been synthesized. Stirring of (LIPdCh) complex with Na B[C6H3(CF3)2]4 in acetonitrile afforded a good yield of the cationic chloroacetonitrile complex [LIPdCINCCH3t.{B[C6H3(CF3)2k}. This reaction with (L2PdCh) afforded also good yields not of the desired [L2PdCINCCH3t.{B[C6H3(CF3)2k} but of the dimer [(L2PdCI)2]2+.2{B[C6H3(CF3)2k}. This behaviour has precedent in the literature and might be due to the reduced bulk of this ligand as compared with Ll. [LIPdCINCCH3t.{B[C6H3(CF3)2]4-} has been successfully methylated with Sn(CH3)4 in DCM as solvent affording good yields of the methyl acetonitrile complex [LIPdCH3NCCH3t.{B[C6H3(CF3)2k}. The methylation of the dimer [(L2PdCI)2]2+.2{B[C6H3(CF3)2]4-} failed in DCM but was succesful in acetonitrile affording a good yield of [L2PdCH3NCCH3t.{B[C6H3(CF3)2]4-}. These palladium methyl acetonitrile complexes have been tested for ethylene, I-hexene and cyclopentene polymerization. Branched polyethylene and polyhexene with relatively high molecular weight have been produced by these catalysts. Catalyst [LIPdCH3NCCH3t.{B[C6H3(CF3)2]4-} was more active and produced higher molecular weight and less branched polymer than catalyst [L2PdCH3NCCH3t.{B[C6H3(CF3)2k } in the polymerization of ethylene. The opposite trend has been observed for I-hexene polymerization where catalyst [L2PdCH3NCCH3t.{B[C6H3(CF3)2k} was more active and produced higher molecular weight polymer than catalyst [LIPdCH3NCCH3t.{B[C6H3(CF3)2]4-}. Atactic polycyclopentene with much lower T g and T m than the ones reported in the literature for isotactic polycyclopentene, has been obtained with these catalysts. Tacticity was determined by 13CNMR.

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20

Johnson, Adam Reid 1971. "Low-valent and low-coordinate titanium and molybdenum complexes supported with bulky amido ligands." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10220.

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21

Stokes, Sheree Lynell 1971. "Synthesis and characterization of iron complexes supported by bulky amide ligands : reduction and oxidation chemistry." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9856.

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22

Champouret, Yohan D. M. "Late transition metal complexes of bulky mono- and bi-nucleating ligands : synthesis and catalytic applications." Thesis, University of Leicester, 2006. http://hdl.handle.net/2381/29977.

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In Chapter One, a background to the application of binucleating ligands in biomimetic chemistry sets the scene for a comprehensive discussion of homogeneous catalysis in the field. Chapter Two describes the strategies employed for the preparation of sterically encumbered multidentate oligopyridylimine ligands. In Chapters Three and Four, the new oligopyidylimine ligands prepared in Chapter Two are treated with divalent metal halides (iron, cobalt, nickel, zinc) and the resultant complexes fully characterised. Specifically, Chapter Three focuses on the reactivity of the potentially pentadentate ligands [bis(imino)terpyridine and imino-quaterpyridine] while Chapter Four concentrates on the resulting coordination chemistry of the potential tetra-, hexa- and hepta-dentate ligands [imino-terpyridine, bis(imino)quaterpyridine and bis(imino)quinquepyridine]. In both chapters, theoretical calculations (DFT) on pre-identified complexes are used in order to investigate the effect of the R substituent (H vs. Me) and metal centre on the coordination chemistry of the ligand. To conclude the synthetic work, the screening for polymerisation or oligomerisation of ethylene is systematically investigated with a selection of the new complexes. In Chapter Five, the synthesis of multidentate ligands featuring sterically encumbered imino-pyridine end-groups linked by phenyl-, thiophene- and phenolate-spacers is studied. The new (pro)ligands are fully characterised and their coordination chemistry with the same series of divalent metal halides is investigated. Furthermore, derivatisation of pre-identified bimetallic complexes is performed. Finally, a selection of the bimetallic compounds is screened as precatalysts for the oligomerisation and/or polymerisation of ethylene.

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23

謝文忠 and Man-chung Tse. "Syntheses, structural studies and photophysical properties of mono, diand polynuclear d10-metal complexes with bulky and electron-richphosphine ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31241086.

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24

Gianopoulos, Christopher G. "Development of Bulky Dipyrromethene Complexes of Aluminum, Zinc, and Rhodium." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418317025.

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25

Maekawa, Miyuki [Verfasser]. "Coordination chemistry of bulky alkyl substituted cyclopentadienyl and indenyl ligands with manganese, iron and cobalt / Miyuki Maekawa." München : Verlag Dr. Hut, 2014. http://d-nb.info/1064560105/34.

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26

Tse, Man-chung. "Syntheses, structural studies and photophysical properties of mono, di and polynuclear d10-metal complexes with bulky and electron-rich phosphine ligands /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21490181.

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27

MacKinnon, I. A. "Some aspects of the chemistry of bulky alkoxide ligands OCBu't3Ì² and OCBu't2Ì²CH2Ì²PR2Ì² (R = Me or Ph)." Thesis, University of Sussex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379498.

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28

Isobe, Toru. "Synthesis of polychalcogenoether ligands tethered with bulky substituents and their application to the synthesis of transition metal complexes." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136902.

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29

Hamaki, Hirofumi. "Synthesis, structure, reactivity and catalytic activities of group 4 metal complexes with novel β-diketiminato ligands bearing bulky substituents". 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136794.

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30

Nagata, Kazuto. "Studies on the synthesis and properties of the disulfur and diselenium complexes of platinum utilizing new bulky phosphine ligands." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/149099.

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31

Shimizu, Daisuke. "Synthesis of novel polythioether ligands bearing bulky substituents and their applications to the synthesis of the transition metal complexes." 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144211.

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32

Maekawa, Miyuki [Verfasser], and Marc Daniel [Akademischer Betreuer] Walter. "Coordination chemistry of bulky alkyl substituted cyclopentadienyl and indenyl ligands with manganese, iron and cobalt / Miyuki Maekawa ; Betreuer: Marc Daniel Walter." Braunschweig : Technische Universität Braunschweig, 2014. http://d-nb.info/1175820466/34.

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33

Köhne, Ingo [Verfasser], Dietmar [Akademischer Betreuer] Stalke, Edmone [Gutachter] Roffael, and Franc [Gutachter] Meyer. "Novel Bulky Bis(benzoxazol-2-yl)methane Ligands in s-Block Metal Coordination / Ingo Köhne ; Gutachter: Edmone Roffael, Franc Meyer ; Betreuer: Dietmar Stalke." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1159768986/34.

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34

Wambua, Pasco M. "Chemistry of Magnesium and Zinc Complexes Supported by Bulky Ancillary Ligands and their Applications in the Ring-Opening Polymerization Studies of Cyclic Esters." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406125367.

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35

Peace, Richard John. "Bulky ligand systems containing pi-acidic aryl and carboranyl groups." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5388/.

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This thesis describes studies into the synthesis and coordination chemistry of ligands containing bulky π-acidic groups. Both π-acidic aryl and carboranyl groups have been investigated. Chapter One highlights electronic and structural aspects of ligands investigated and computational techniques employed. Chapter Two describes the synthesis of aromatic systems bearing nitrogen substituents and trifluoromethyl groups, with a view to their use in the synthesis of new ligands. The π -interaction between the nitrogen substituent and aromatic ring has been investigated and is found to vary considerably with the nature of the substituent and position of the CF(_3) groups on the ring. Chapter Three describes the synthesis of molybdenum compounds containing CF3 substituted aryl-imido ligands. The presence of the π-acidic group is found to decrease π-bonding from the ligand to the metal which results in changes in the reactivity of such complexes. Chapter Four describes the synthesis of nitrogen-substituted carboranes 1- NHX-2-R-l,2-C(_2)B (_10)H(_10) (R = Me, Ph; X = 2-R-l,2-C(_2)B(_10)H(_10), NHAr, OH, H) and 1- NX-2-R-C(_2)B(_10)H(_10) (R = Me, Ph; X = 0, NAr). The structures of many of these compounds are described and the π-interaction between the cage and substituent investigated. This 7t-interaction determines the orientation of the substituent relative to the cage and causes changes in the geometry of the cage. The "B NMR shift of the atom directly opposite the nitrogen substituent is found to give an accurate indication of the exo π-bond order. In light of these observations data from other systems have been re-examined. Chapter Five describes the incorporation of carborane containing ligands into metal systems. The π-acidic carboranyl group reduces 7i-bonding from the ligand to the metal. The consequences of this on the structure and reactivity of these complexes are discussed. Chapter Six gives experimental details for Chapters Two to Five. Richard John Peace (August 1996).

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36

Maria, Felipe Henrique Santa. "Análise térmica da influência do oxigênio na amorfização de ligas baseadas em Cu-Zr." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18158/tde-23052018-105250/.

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Os vidros metálicos baseados em Cu-Zr representam uma classe bastante promissora para a categoria de materiais estruturais, tendo em vista suas interessantes propriedades resultantes da natureza amorfa. Sabe-se que o oxigênio tem grande influência na formação da estrutura amorfa e consequentemente nas propriedades dessa classe de materiais. No presente trabalho, ligas amorfas baseadas em Cu-Zr foram analisadas termicamente a fim de se observar o comportamento das mesmas frente à contaminação com oxigênio. As análises térmicas foram realizadas em um equipamento de calorimetria exploratória diferencial (DSC), e as temperaturas características como de transição vítrea, cristalização, fusão e líquidus foram determinadas. Concluiu-se que conforme a literatura apresenta, o processo de cristalização é favorecido pela presença de oxigênio, causando uma queda na energia de ativação dos processos de cristalização das ligas trabalhadas. Através de ensaios que simularam tratamentos térmicos, cristalizou-se controladamente as amostras amorfas baseadas em Cu-Zr a fim de formar compósitos entre cristais e vidros metálicos buscando diminuir a fragilidade das ligas.<br>Cu-Zr-based bulk metallic glasses represent a very promising class of structural materials with interesting properties resulting from the amorphous nature. It is known that oxygen has a great influence on the formation of the amorphous structure and consequently on the properties of these materials. In the present work, Cu-Zr-based amorphous alloys were thermally analyzed in order to observe their behavior against oxygen contamination. Thermal analyzis were performed on a differential scanning calorimetry (DSC) equipment, and characteristic temperatures as glass transition, crystallization, melting and liquidus were determined. It was concluded that, according to the literature, the crystallization process is favored by the presence of oxygen, causing a decrease in the activation energy of the crystallization processes of the worked alloys. Through tests that simulated heat treatments, the amorphous samples were crystallized in order to form composites between crystals and metallic glasses in order to reduce the brittleness of the alloys.

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37

Noor, Awal. "Early transition metal complexes stabilized by bulky aminopyridinato ligands." 2008. http://opus.ub.uni-bayreuth.de/volltexte/2008/454/.

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38

Wiacek, Robert Johnny. "The use of bulky ligands for the stabilization of group 15 radicals and cations." 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3099515.

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39

Yang, Zhi. "Synthesis, Reactivity, and Structural Elucidation of Aluminum Compounds with Bulky Ligands." Doctoral thesis, 2007. http://hdl.handle.net/11858/00-1735-0000-0006-AC8D-7.

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40

Lee, Jian-Cheng, and 李堅呈. "Palladium Catalyzed Aryl Amine Formation Using Cobalt-containing Bulky Phosphine Ligands." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/96191169010019946850.

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碩士<br>國立中興大學<br>化學系<br>93<br>Aromatic amines play a key role in a number of fields. These include pharmaceuticals, agrochemicals, photography, xeroxography, pigments and electronic materials. One of the most revealing facts is that in 1994’s list of the twenty top-selling pharmaceuticals, a significant number contained aromatic carbon-nitrogen bonds. We use Dewar-Chatt-Duncanson’s Model principle, and develop several dicobalt-containing phosphine ligands. The applications of these ligands in the amination reactions were pursued. Palladium catalyzed amination reactions using bromobenzene and morpholine as reaction substrates, were carried out by employing the cobalt-containing phosphine ligand 1 chelated palladium complex. It was found that in the case of 1:Pd(OAc)2 the performance is better with the ratio of 1:1 than 2:1. A novel palladium complex, [1-H+]-Pd(OAc) 2, was obtained from the reaction of a dicobalt-containing mono-phosphine ligand, [(-PPh2CH2PPh2) Co2(CO)4][-PhC≡CP(t-Bu)2] 1 with Pd(OAc)2. As revealed by the crystal structure, a process of ortho-metallation took place and presumably accompanied by the release of one equivalent of acetic acid. 2 is a stable compound and is not regarded as the active species in amination reactions.

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41

"Group 4 transition-metal and lanthanide complexes supported by bulky amino ligands." Thesis, 2011. http://library.cuhk.edu.hk/record=b6075208.

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Ku, Ka Wai.<br>Thesis (Ph.D.)--Chinese University of Hong Kong, 2011.<br>Includes bibliographical references.<br>Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.<br>Abstract also in Chinese.

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42

Noor, Awal [Verfasser]. "Early transition metal complexes stabilized by bulky aminopyridinato ligands / vorgelegt von Awal Noor." 2008. http://d-nb.info/989833038/34.

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43

"Synthesis and reaction chemistry of divalent metal complexes derived from bulky guanidinate ligands." 2013. http://repository.lib.cuhk.edu.hk/en/item/cuhk-1292021.

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Wong, Fai George.<br>Thesis Ph.D. Chinese University of Hong Kong 2013.<br>Includes bibliographical references.<br>Abstracts also in Chinese.<br>Title from PDF title page (viewed on 16, December, 2016).

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44

Gwynne, Erin. "Synthesis, Characterization, and Hydrogenation Activity of Group 10 Metal Complexes Featuring Bulky Phosphine Ligands." Thesis, 2010. http://hdl.handle.net/1807/24576.

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Bulky, electron-rich phosphine ligands facilitate unique reactivity in various chemical systems and can stabilize metal species in unusual oxidation states or environments. Routes to bulky bis(phosphine) chelating ligands that mimic the sterics of the exceptionally bulky tri-tert-buylphosphine are explored with the ultimate goal of preparing novel catalyst systems of group 10 metals capable of hydrogenation. Attempts to target bulky phosphines from phosphinimine precursors highlight some interesting phosphinimine reactivity, however attempts to reduce the phosphinimine bond revealed limitations. Bis(aminophosphine) ligands present an alternate route to bulky bis(phosphines) and allow for tunability of the environment around phosphorus. The coordination of these ligands with palladium and nickel exhibit a novel bonding mode in which C-H or N-H activation of the ligand occurs to form strained metallacycles. Prepared compounds showed some activity as catalysts under hydrogen and isomerized 1-hexene to 2-hexene, offering support for their potential use as hydrogenation catalysts.

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45

"The coordination chemistry of sterically bulky guanidinate ligands with chromium and the lanthanide metals." 2014. http://library.cuhk.edu.hk/record=b6115525.

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本項研究工作主要對五個結構類似的胍基配體，即 [(2,6-Me₂C₆H₃N)C(NHPri)(NPri)]⁻ (L¹)， [(2,6-Me₂C₆H₃N)C(NHCy)(NCy)]⁻ (L²)， [(2,6-Me₂C₆H₃N)C{N(SiMe₃)Cy}(NCy)]⁻ (L³)， [(2,6-Pri₂C₆H₃N)C{N(SiMe₃)₂}(NC₆H₃Pri₂-2,6)]⁻ (L⁴) 和 [(2,6-Pri₂C₆H₃N)C(NEt₂)(NC₆H₃Pri₂-2,6)]⁻ (L⁵) 與二價鉻以及二價鑭系金屬[Sm(II)、Eu(II) 及 Yb(II)] 的配位化學進行研究，同時，一系列由 L¹ 配體所衍生的三價鑭系金屬配合物亦成功被合成。<br>第一章概括介紹了由胍基配體所構築的金屬配合物的研究背景。<br>第二章敍述了含 L¹ 與 L⁴ 的二價鉻配合物的合成、結構及其化學反應。通過胍基鉀化合物 [KL¹･0.5PhMe] (1) 與二氯化鉻反應可得到單核二價鉻雙胍基配合物 [Cr(L¹)₂] (3)。通過胍基鋰化合物 [LiL⁴(Et₂O)] (2) 與二氯化鉻反應，成功製備了單胍基二價鉻配合物 [Cr(L⁴)(μ-Cl)₂Li(THF)(Et₂O)] (4)。而把二價鉻配合物 4於甲苯溶液中重結晶可得到二聚體的二價鉻配合物 [{Cr(L⁴)(μ-Cl)}₂] (5)。另外，我們對二價鉻配合物 3 及 4 的反應特性也進行了研究。 [Cr(L¹)₂] (3) 與單質碘、二苯基硫族化合物 PhEEPh (E = S, Se, Te) 以及叠氮金剛烷反應可得相對應的三價鉻混合配體化合物，分別爲 [Cr(L¹)₂I] (6)、[Cr(L¹)₂(EPh)] [E = S (7), Se (8), Te (9)]，及四價鉻配合物 [Cr(L¹)₂{N(1-Ad)}] (10)。透過單胍基二價鉻配合物 [Cr(L⁴)(μ-Cl)₂Li(THF)(Et₂O)] (4) 與 NaOMe反應可得甲氧基-胍基配合物 [{Cr(L⁴)(μ-OMe)}₂] (11)。<br>第三章主要報導含 L¹， L²， L³ 和 L⁵ 配基的二價鑭系配合物的合成、結構和化學反應特性。透過 [LnI₂(THF)₂] (Ln = Sm, Eu, Yb) 與胍基鉀鹽反應，我們成功合成一系列二價鑭系絡合物，包括 [{Eu(L¹)(μ-L¹)}₂] (15)， [{Ln(L²)(μ-L²)}₂･nC₆H₁₄] [Ln = Eu, n = 2 (16); Ln = Yb, n = 0 (17)，[Yb(L²)₂(THF)₂] (18)， [Ln(L³)₂(THF)₂･0.25C₆H₁₄] [Ln = Eu (19), Yb (20)]， [{Sm(L³)(μ-I)(THF)}₂] (21) 和 [Sm(L⁵)₂] (22)。本章亦同時探討二價鑭系配合物15， 18， 20 和 22 作爲還原劑的化學反應特性。配合物 15 與單質碘反應可得三價銪配合物 [{Eu(L¹)₂(μ-I)}₂] (23)。配合物 18 與二苯基硫族化合物 PhEEPh (E = S, Se) 反應，可得相對應的三價鐿配合物 [{Yb(L²)₂(μ-EPh)}₂] [E = S (24), Se (25)]。 18 與氯化亞銅反應得到三價鐿配合物 [{Yb(L²)₂(μ-Cl)}₂] (26)。除此之外，配合物 18 與偶氮苯反應得到雙核配合物 [{Yb(L²)₂}₂(μ-η²:η²-PhNNPh)] (27)，而 20 與偶氮苯的反應可得單核配合物 [Yb(L³)₂(η²-PhNNPh)･PhMe] (28)。配合物 22 與二硫化碳的反應得出不對稱偶合配合物 [(L⁵)₂Sm(μ-η³:η²-S₂CSCS)Sm(L⁵)₂] (29)。<br>第四章敍述由胍基配體 L¹ 所衍生的一系列三價鑭系金屬配合物 [Ln(L¹)₃] [Ln = Ce (30), Pr (31), Gd (32), Tb (33), Ho (34), Er (35), Tm (36)] 的合成及其結構。通過相對應的鑭系金屬三氯化物與 1 反應可得配合物 30-36。另外， CeCl₃及 LuCl₃與 1 反應亦可合成 [{Ln(L¹)₂(μ-Cl)}₂] [Ln = Ce (37), Lu (38)]。<br>第五章總結了本項研究工作，並對本工作的未來發展作出建議。<br>This research work is focused on the coordination chemistry of five closely related guanidinate ligands, namely [(2,6-Me₂C₆H₃N)C(NHPri)(NPri)]⁻ (L¹), [(2,6-Me₂C₆H₃N)C(NHCy)(NCy)]⁻ (L²), [(2,6Me₂C₆H₃N)C{N(SiMe₃)Cy}(NCy)]⁻ (L³), [(2,6Pri₂C₆H₃N)C{N(SiMe₃)₂}(NC₆H₃Pri₂-2,6)]⁻ (L⁴) and [(2,6-Pri₂C₆H₃N)C(NEt₂)(NC₆H₃Pri₂-2,6)]⁻ (L⁵), with divalent chromium and lanthanide metal ions. A series of trivalent lanthanide derivatives of the L¹ ligand were also prepared and structurally characterized in this work.<br>Chapter 1 gives a brief introduction to the chemistry of metal guanidinate complexes.<br>Chapter 2 reports on the synthesis, structure and reactivity of chromium(II) complexes derived from the bulky L¹ and L⁴ ligands. Treatment of CrCl₂ with [KL¹･0.5PhMe] (1) afforded the mononuclear Cr(II) bis(guanidinate) complex [Cr(L¹)₂] (3). Reaction of CrCl₂ with [LiL⁴(Et₂O)] (2) resulted in the isolation of ate-complex [Cr(L⁴)(μ-Cl)₂Li(THF)(Et₂O)] (4). Recrystallization of 4 from toluene gave neutral, dimeric [{Cr(L⁴)(μ-Cl)}₂] (5). The reaction chemistry of the Cr(II) complex 3 and 4 was studied. Treatment of 3 with I₂, PhEEPh (E = S, Se, Te), 1-AdN₃ (1-Ad = 1-adamantyl) gave the corresponding mixed-ligand Cr(III) complexes, namely [Cr(L¹)₂I] (6) and [Cr(L¹)₂(EPh)] [E = S (7), Se (8), Te (9)] and Cr(IV) complex [Cr(L¹)₂{N(1-Ad)}] (10). Besides, the reaction of 4 with NaOMe resulted in the isolation of the Cr(II) methoxide-guanidinate complex [{Cr(L⁴)(μ-OMe)}₂] (11).<br>Chapter 3 deals with the synthesis, structure and reactivity of lanthanide(II) complexes supported by the L¹, L², L³ and L⁵ ligands. Lanthanide(II) guanidinate complexes were prepared by the reactions of an appropriate lanthanide diiodide with the corresponding potassium guanidinate complexes [KL¹･0.5PhMe] (1), [KL²(THF)₀.₅]n (12), KL³ (13) and [KL⁵(THF)₂] (14). Reaction of EuI₂(THF)₂ with 1 gave the homoleptic complex [{Eu(L¹)(μ-L¹)}₂] (15). Metathesis reactions of LnI₂(THF)₂ (Ln = Yb, Eu) with 12 and 13 led to the isolation of [{Ln(L²)(μ-L²)}₂･nC₆H₁₄] [Ln = Eu, n = 2 (16); Ln = Yb, n = 0 (17)], [Yb(L²)₂(THF)₂] (18) and [Ln(L³)₂(THF)₂･0.25C₆H₁₄] [Ln = Eu (19), Yb (20)]. Direct reaction of SmI₂(THF)₂ with 13 yielded the iodide bridged Sm(II) complex [{Sm(L³)(μ-I)(THF)}₂] (21), whilst reaction of SmI₂(THF)₂ with 14 gave homoleptic [Sm(L⁵)₂] (22). The reaction chemistry of 15, 18, 20 and 22 as reducing agents was examined. Oxidation of 15 with I₂ afforded the Eu(III) complex [{Eu(L¹)₂(μ-I)}₂] (23). Reactions of 18 with PhEEPh (E = S, Se) gave the corresponding Yb(III) chalcogenide complexes [{Yb(L²)₂(μ-EPh)}₂] [E = S (24), Se (25)], whilst treatment of 18 with CuCl led to the isolation of [{Yb(L²)₂(μ-Cl)}₂] (26). Besides, addition of complex 18 to PhNNPh yielded binuclear [{Yb(L²)₂}₂(μ-η²:η²-PhNNPh)] (27), whereas treatment of 20 with PhNNPh resulted in the isolation of mononuclear [Yb(L³)₂(η²-PhNNPh)･PhMe] (28). Addition of CS₂ to 22 gave the unsymmetrical coupling product [(L⁵)₂Sm(μ-η³:η²S₂CSCS)Sm(L⁵)₂] (29).<br>Chapter 4 describes the preparation and structural characterization of lanthanide(III) complexes derived from L¹. A series of homoleptic lanthanide(III) tris(guanidinate) complexes [Ln(L¹)₃] [Ln = Ce (30), Pr (31), Gd (32), Tb (33), Ho (34), Er (35), Tm (36)] were prepared by the reactions of an appropriate LnCl₃ with three molar equivalents of 1. Treatment of CeCl₃ and LuCl₃ with two equivalents of 1 gave the corresponding chloride bridged guanidinate complexes [{Ln(L¹)₂(μ-Cl)}₂] [Ln = Ce (37), Lu (38)].<br>Chapter 5 summarizes the findings of this study. A short description on the future prospect of this work will also be given.<br>Detailed summary in vernacular field only.<br>Detailed summary in vernacular field only.<br>Detailed summary in vernacular field only.<br>Detailed summary in vernacular field only.<br>Detailed summary in vernacular field only.<br>Detailed summary in vernacular field only.<br>Au, Chi Wai.<br>Thesis (Ph.D.) Chinese University of Hong Kong, 2014.<br>Includes bibliographical references.<br>Abstracts also in Chinese.

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Yang, Zhi [Verfasser]. "Synthesis, reactivity, and structural elucidation of aluminum compounds with bulky ligands / vorgelegt von Zhi Yang." 2007. http://d-nb.info/984694676/34.

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Zhu, Hongping [Verfasser]. "The reaction chemistry of aluminum(I, III) compounds stabilized by sterically bulky ligands / vorgelegt von Hongping Zhu." 2005. http://d-nb.info/977037711/34.

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mingin-Wang and 王敏靖. "Investigation of Suzuki, Amination and Heck Reactions by Employing Palladium Complexes Having Metal-containing Bulky Phosphine Ligands." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/30458433554559701760.

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碩士<br>國立中興大學<br>化學系<br>93<br>Two bulky, mono-dentate alkyne-bridged dicobalt-phosphine complexes [(m-PPh2CH2PPh2)Co2(CO)4](m,h-PhC≡CP(ipr)2) 3, [(m-PPh2CH2PPh2)Co2(CO)4](m,h-Me3C≡CPcy2) 5 have been proved to be effective monodentate phosphine ligands in theseSuzuki, Amination and Heck Reactions .

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Hsin-Pei, Chen, and 陳鑫培. "Catalyst of Transition Metal Complexes with Bidentate Steric Bulky P-N Ligands on Polymerization and Coupling Reactions." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/10445665600228892956.

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博士<br>國立臺灣大學<br>化學研究所<br>91<br>New P~N ligands with bulky substituents and their transition metal complexes were prepared in this study. Unusual coordination phenomena and interesting C-H activation in cationic Pd complexes were observed in ligands 2a and 2b, when t-Bu group was introduced on the pyridine ring at a position. In this case the ligands behave P~N~C tridendates more likely in cationic Pd complexes. The influence of temperature toward C-H activation was also investigated. When another steric bulky ligands(10a, 10b) with mesityl as the substituent were adopted, the P~N chelated Pd complexes were achieved after reacting with [(COD)PdMeCl]. The cationic Pd complexes can be obtained by remove of Cl-, and the stepwise CO and olefin insertion reactions of these cationic complexes were also discussed in this research. All the complexes were characterized by NMR, IR and X-ray analysis. Activity of these complexes toward polymerization/co- polymerization with some a olefins and/or CO was investigated, whereas Pd complexes show less activity. However, compared with the other P~N complexes synthesized by our lab in ethylene oligomerization reaction base on FAB analysis. There were 14 ethylene units inserted into the Pd center which indicate that the sreric hindrance of the ligands effectively reduce the b-hydrogen elimination. Different from the Pd complexes, the Ni complexes with MAO as cocatalyst in ethylene oligomerization which behave extreme activity .The T.O.F. can be up to 9.5×105 g mol-1 h-1 and the dimers and trimers can be collected. On the other hand, highly crystallinic P.E. can be obtained as the less amount of MAO is used. The m.p. of the crystallinic P.E. range from 115 to 121℃. The Ni(II) and Cu(I) complexes used as catalyst in different kinds of intermolecular coupling reactions were also studied in this research. All of these catalysts show activity in different kinds of reactions, and the yield were calculated by G.C and N.M.R. analysis.

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Bor-Hunn, Huang. "Synthesis, Characterization and Structural Determination of Lithium and Magnesium Complexes Stabilized by New Ancillary Bulky Ligands BCP from Application of Lactide Polymerization: Nanostructure and Nanotemplate from Self-Assembly of Biodegradable Block Copolymers." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0005-2508200611310300.

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