Dissertations / Theses: 'Group III metal complexes'

1

Caporale, Angelamaria. "Synthesis of novel ligands for the stabilization of organometallic complexes having potential antitumor activity." Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2191.

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2014 - 2015
The design of new metal complexes as anticancer agents has received considerable interest in recent years. Complexes of titanium (e.g.: titanocene dichloride), lanthanides complexes (e.g.: texaphyrrins lanthanide) and carbenic complexes of gold, silver and copper showed significant biological activity, and have progressed into clinical trials. Thus, the target of this PhD project are the synthesis of new ligands and metal complexes. Firstly 5 cyclopentadienyl pro-ligands were synthesised: 6-phenylfulvene, 6-(p-metoxyphenyl)-fulvene e 6- (3',4'-dymethoxyphenyl)fulvene, 6-(3',5')-dymethoxyphenyl)fulvene and 6-(2',4')- dymethoxyphenyl)fulvene. Then, the synthesis of 12 novel scandium, yttrium and neodymium complexes with these cyclopentadienyl ligands was carried out. The complexes were tested on DU146 (Prostatic carcinoma) and MDA.MB213 (Breast cancer) to verify inhibition of cell-proliferation, using MTT test with standard procedures. All the complex showed a strong concentration-dependent ability of inhibiting the growth tumor cell, referring to antiblastic activity. [edited by author]
XIV n.s.

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2

Popham, Michael Charles. "Complexes of Group III metal salts and titanium halides with tertiary pnictogen oxide and crown ether ligands." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274472.

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3

Le, Mest Yves. "Etude des propriétés électrochimiques de biporphyrines de type "face-à-face" : réactivité des dérives du cobalt vis-à-vis de l'oxygène." Brest, 1988. http://www.theses.fr/1988BRES2013.

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4

Webb, Kevin James. "Sterically hindered chalcogenolato complexes of group IIB metals." Thesis, University of East Anglia, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316298.

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5

Pounds, Thomas John. "Redox group-functionalised diphosphine complexes." Thesis, University of Liverpool, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367302.

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6

Gash, Rosslyn Clare. "Metal haloalkyl in complexes in catalysis." Thesis, University of St Andrews, 1993. http://hdl.handle.net/10023/14706.

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In this thesis, the preparation of a number of halomethyl complexes of rhodium, platinum, and palladium is described. Complexes of the type trans-[Rh(CH2X)X(P4)]+ (X = Cl, Br, I, P = PMe3, dmpe) were found to be unstable, decomposing in situ to give a mixtures of dihalo, trihalo, and phosphine ylide species. Platinum and palladium species of the type trans-M(CH2X)X(PEt3)2 (X = Cl, I, M = Pt, Pd), which were formed by the reaction between M(PEt3)3 CH2XY were also unstable. In the case of platinum, phosphine ylide species were isolated from reaction mixtures, whilst the palladium halomethyl species decomposed over a number of days to give dihalide complexes. However, palladium iodomethyl species prepared via reactions involving 2 moles of phosphine per mole of metal were found to be stable. Neutral rhodium halomethyl complexes were also found to be far more stable than their cationic counterparts. The synthesis and characterisation of trans-RhCl(CO)(CH2l)I(P)2/ (P = PMe3, PEt3, or Et2PPh), prepared by oxidative addition of CH2I2 to RhCl(CO)(P)2 is described. When less basic phosphines (such as PPh3) or the sterically hindered phosphine PCy3 were used, no evidence of any reaction between the rhodium complex and the CH2I2 was observed. The molecular structure of trans-RhCl(CO)(CH2l)I(PEt3)2 has been studied by X-ray diffraction analysis. This complex proved to be inert to substitution at the iodomethyl carbon atom by neutral nucleophiles such as H2O, CH3OH, and PEts, but prone to substitution by Cl-. The lability of iodomethyl (and chloromethyl) ligands towards CO insertion has also been studied. There is evidence to suggest that an iodoacyl platinum complex may form in solution after the complex cis-Pt(CH2l)I(PPh3)2 had been left under 1 atm CO for 24 hours. However, in the case of trans-Pd(CH2l)I(PCy3)2 this same reaction took 7 days under 70 atm pressure of CO. All of the rhodium iodomethyl complexes prepared were also inert to CO insertion at ambient temperature and 1 atm CO, but excellent evidence for CO insertion having taken place in irflns-RhCl(CO)(CH2l)I(PEt3)2 was observed at 70°C and 35 atm of CO. Evidence for CO insertion into a rhodium-chloromethyl bond was also observed under the more forcing conditions of 100°C and 70 atm CO. This insertion reaction may prove to be extremely useful in catalytic systems. A report of some preliminary catalytic studies involving the production of diethylmalonate from CH2I2 and C2-products from the hydroformylation of (CH2O)[sub]n under very mild conditions is also presented. It is thought that these catalytic reactions proceed via carbonyl insertion into a rhodium-iodomethyl bond.

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7

Harding, David James. "Redox-active group 6 transition metal alkyne complexes." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324328.

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8

Bell, Michael Niall. "Organometallic platinum group metal complexes incorporating macrocyclic ligands." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/13895.

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9

Campbell, Michael Glenn. "Synthesis, Structure, and Reactivity of New Palladium(III) Complexes." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11289.

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Palladium is one of the most common and versatile transition metals used in modern organometallic chemistry. The chemistry of palladium in its 0, +II, and +IV oxidation states is well-known; by comparison, the chemistry of palladium in its +III oxidation state is in its infancy. The work in this thesis involves the study of previously unknown Pd(III) complexes, including applications in materials chemistry and catalysis.
Chemistry and Chemical Biology

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10

Parsons, Teresa L. "Technetium(V), Rhenium(V), and Technetium(III) complexes /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9840026.

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11

Jefferis, Jesse Mark. "The preparation and reactivity of group 5 indenyl complexes." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/958792.

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The preparation of tri-n-butylstannylindene, has led to new synthetic routes to obtaining indenyl metal complexes of the Group V metal halides. Also, the fluxional behavior of tri-n-butylstannylindene has been studied by variable temperature 1H NMR spectroscopy.The interaction of the Group V metal halides with tri-n-butylstannylindene has led to the isolation and characterization of [(q5-C9H7)2TaC12] [TaC16] and [('q5-C9H7)2NbC12] [NbCl6]. Subsequent Lewis base chemistry has produced (T15-C9H7)TaC14(PMe3). The crystal structures of [(r15-C9H7)2TaCl2] [TaC16] and (15-C9H7)TaC14(PMe3) have been determined. The preparation and characterization of these compounds are discussed as well as the exploratory indenyl, Lewis base, and /or salt chemistry of vanadium, niobium, and tantalum.
Department of Chemistry

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12

Baxter, Paul N. W. "Substituted #alpha#-diimine complexes of group VI metal carbonyls." Thesis, University of Kent, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279680.

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13

Boonyuen, Supakorn. "The redox chemistry of Group 6 metal alkyne complexes." Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420906.

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Riddlestone, Ian Martin. "Synthesis and reactivity of transition metal-group 13 complexes." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:f253a2a5-cc6e-4978-86d9-5f3064dadc1b.

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The synthesis and reactivity of a number of mixed transition metal-aluminium and σ-alane complexes are detailed in this thesis. Chapter III reports on the formation and structural characterisation of N,N'-chelated aluminium dihalide precursors featuring amidinate and guanidinate substituents. These precursors of the type RC(R'N)₂AlX₂ (R = ⁱPr₂N or Ph; R' = Cy or ⁱPr or Dipp; X = hal), readily react with Na[CpFe(CO)₂] via salt elimination to form the corresponding mixed iron-aluminium complexes CpFe(CO)2[(X)Al(NR')2CR] which have been characterised both spectroscopically and by X-ray diffraction. The reactivity of the novel mixed aluminium-iron complexes towards halide abstraction agents has been investigated and a propensity for augmented coordination at the aluminium centre observed. Furthermore, complementary syntheses of the methyl substituted complex CpFe(CO)₂[(Me)Al(NCy)₂CNⁱPr₂] have been developed. This can be achieved either via the reaction between the related chloride complex and MeLi, or from the reaction between ⁱPr₂C(CyN)₂Al(Me)Cl and Na[CpFe(CO)₂]. The research detailed in Chapter IV builds on the previous chapter and is focussed on the use of more sterically demanding substituents at both aluminium and transition metal, as well as more electron rich transition metal fragments. The transition metal anions Na[Cp*Fe(CO)₂] and Na[Cp^SiFe(CO)(PPh₃)] react with the aluminium precursors forming related mixed iron-aluminium complexes which have been structurally characterised. The Dipp₂NacNacAlCl₂ precursor has been shown to undergo reaction with both Na[CpFe(CO)₂] and Na[Cp*Fe(CO)₂]. The halide abstraction chemistry of the latter utilising both Lewis acid and salt metathesis based abstraction approaches has been investigated. The dehydrohalogenation chemistry of the Dipp₂NacNacAlCl₂ precursor was investigated and the ligand activated products of reactions with both alkyl lithium and alkyl potassium reagents characterised. Chapter V reports the extension of salt metathesis for the formation of an Al-H-Mn interaction, and the product has been fully characterised. In addition, the coordination of Al-H bonds from a number of alane precursors to in situ generated 16-electron fragments has allowed the structural characterisation of a number of novel σ-alane complexes. The incorporation of the transition metal fragments [Cp'Mn(CO)₂] and [W(CO)₅] permit comparison to archetypal borane and silane σ-complexes. Quantum chemical calculations suggest that the alane ligand has a binding energy close to that of dihydrogen but significantly less than that of CO, consistent with a predominant σ-donor role of the Al-H bond. The formation and structural characterisation of the κ²-complexes (OC)₄M[κ²-H₂AlDipp₂NacNac] (M = Cr, Mo or W) define an unprecedented binding motif for the alane ligand. In the cases of chromium and molybdenum the κ²-complexes can be prepared either photolytically or via alkene displacement from the corresponding (OC)₄M(cod) reagent. In the case of tungsten the alkene displacement route yields the desired product, but only under more forcing conditions. Spectroscopic characterisation of the related κ¹-complex (OC)₅Cr[κ¹-H₂AlDipp₂NacNac], which readily forms the κ²-complex in solution without photolysis, has enabled the kinetics of chelate ring closure to be investigated. This analysis further characterises the formation of the unprecedented κ²-binding motif for the alane ligand.

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15

Pierssens, Luc Jean-Marie. "Aspects of subvalent group 14 metal chemistry." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360491.

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16

陳展榮 and Chin-wing Chan. "Transition metal complexes of quaterpyridines and photochemical studies of cyclometallated gold(III) and platinum(II) complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B31233454.

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17

Chan, Chin-wing. "Transition metal complexes of quaterpyridines and photochemical studies of cyclometallated gold(III) and platinum(II) complexes /." [Hong Kong : University of Hong Kong], 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13671753.

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18

Coles, Martyn Paul. "Transition metal imido complexes : synthesis and applications to polymerisation catalysis." Thesis, Durham University, 1995. http://etheses.dur.ac.uk/5215/.

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This thesis describes studies into Group 5 and Group 6 transition metal imido complexes, with particular emphasis on the development of complexes which can be applied to catalytic processes. Chapter 1 highlights the electronic and structural aspects of the imido and alkylidene ligands. The isolobal analogy between Group 4 bent metallocene. Group 5 half-sandwich imido and Group 6 bis(imido) metal fragments is outlined. In addition, Ziegler-Natta type a-olefin polymerisation and Ring Opening Metathesis Polymerisation (ROMP) are briefly reviewed. Chapter 2 describes initial screening of half-sandwich vanadium imido and chromium bis((^t)butylimido) dichloride complexes as catalyst precursors. Synthesis of the chromium bis(imido) dialkyl complex Cr(N(^t)Bu)(_2)(CH(_2)Ph)(_2) (1) is described, its conversion to a cationic alkyl species is probed and the polymerisation activity associated with the resultant compound is addressed. Finally this chapter details the synthesis and characterisation of a range of bis(adamantylimido) chromium complexes. Chapter 3 presents a synthetic entry point into the bis(arylimido) chemistry of chromium. The complex Cr(NAr)(_2)(NH(^t)Bu)Cl (12) is described (Ar = 2,6-(^i)Pr(_2)C(_6)H(_3)) and its conversion to the dichloride complex Cr(NAr)(_2)Cl(_2) (14) is examined. 14 forms the stable monoadduct with pyridine, the X-ray crystallographic study of which reveals a distorted square based pyramidal geometry about the chromium atom. The inclusion of the arylimido ligand at the metal centre allows stabilisation of the chromium bis- phosphine complexes Cr(NAr)(_2)(PMe(_3))(_2) (18) and Cr(NAr)(_2)(PMe(_2)Ph)(_2) (19). The reactivity of 18 towards unsaturated hydrocarbon substrates is briefly investigated. Chapter 4 focuses on the organometallic chemistry of the [Cr(NAr)(_2)] moiety. A range of dialkyl derivatives are isolated and the molecular structures of a selection are solved. The generation of the nascent species [Cr(NAr)(_2)(=CHCMe(_3))] is investigated and the conversion of Cr(NAr)(_2)(CH(_2)CMe(_3))(_2) (24) to Cr(NAr)(-2)(CHDCMe(_3))(C(_6)D(_5)) (25) is the subject of a kinetic study. In chapter 5, the ROMP of a series of amino acid derived norbomene monomers is studied. The resultant polymers are fully characterised and a brief molecular modelling study is carried out on representative polymers chain lengths. Chapter 6 contains experimental details to chapters 2-5.

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19

Williams, Daniel M. "Phosphate ester hydrolysis promoted by lanthanide (III) and transition metal complexes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0015/NQ55393.pdf.

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20

Williams, Daniel M. "Phosphate ester hydrolysis promoted by lanthanide (III) and transition metal complexes." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35551.

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Phosphate ester linkages are omnipresent in nature and are found in many biologically important molecules such as DNA, RNA and ATP. Many enzymes that hydrolyze phosphate esters are activated by metal ions. Since the structure of biological enzymes can be quite complicated, it is often useful to work with simpler artificial metalloenzymes to help elucidate the mechanisms by which phosphate ester hydrolysis is activated by metals.
In principle, simple dinuclear metal complexes could hydrolyze phosphate esters by double Lewis acid activation or by a combination of single Lewis acid activation and metal-hydroxide activation. These two mechanisms are kinetically indistinguishable. In this study, two different phosphate substrates are used to distinguish these mechanisms.
Lanthanide (iii) salts have proven extraordinarily effective in accelerating the rate of phosphate ester hydrolysis by several orders of magnitude. Consequently, there has been much effort in recent years to develop a ligand that would bind lanthanides so as to further improve their ability to hydrolyze phosphates. These efforts have met with limited success. Reported here is a dinuclear lanthanide (iii) complex which hydrolyzes BNPP (bis p-nitrophenyl phosphate) with unprecedented reactivity at pH 7.0 and 25°C.
A mononuclear copper (ii) 6,6'-diamino-2,2 '-bipyridyl complex is synthesized which gives one of the fastest rate accelerations reported for hydrolyzing 2',3 '-cAMP. A hydrogen bonding mechanism is proposed for the acceleration of the rate of hydrolysis of the cyclic phosphate.

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21

Wang, Modi. "The application of iridium(iii) complexes in luminescent sensing." HKBU Institutional Repository, 2016. http://repository.hkbu.edu.hk/etd_oa/296.

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Luminescent transition metal complexes have arisen as viable alternatives to organic dyes for sensory applications due to their notable advantages. This thesis aimed to synthesize different kinds of iridium(III) complexes as chemosensors and G-quadruplex probes for the detection of metal ions, small molecules, proteins and DNA to demonstrate the versatility of iridium(III) complex in luminescence sensing. Iridium(III) complex chemosensors were synthesized and developed for the detection of Cu2+ and cysteine. The iridium(III) complex plays the role of the "signaling unit", which transduces the analyte binding event into an optical (luminescent) signal and the "receptor unit" attached to the metal complex selectively binds the analyte of interest. Meanwhile, a series of iridium(III) complexes incorporating a variety of C^N and N^N donor ligands were synthesized and were shown to exhibit G-quadruplex-selective binding properties via emission titration, fluorescence resonance energy transfer melting and G-quadruplex fluorescent intercalator displacement experiments. These G-quadruplex-selective Ir(III) complexes were utilized as signal transducers to monitor the conformational changes of oligonucleotides in label-free oligonucleotide-based luminescent detection platforms for metal ion (Ag+), small molecules (cocaine), protein (insulin and AGR2) and gene deletion.

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22

Hopkins, A. D. "Group 15/alkali metal complexes and applications to photoemissive materials." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604223.

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The research presented in this thesis falls into four related areas. The synthetic approach used in all studies was the stepwise deprotonation of primary amines and phosphines with Group 15 dimethylamido reagents to produce heterobimetallic Group 15/alkali metal complexes. The principal aim was to examine the decomposition of these species, potentially into photoemission alkali metal antimonate layers. After an initial introduction (Chapter 1) detailing previous methods of synthesis of imido heterobimetallic complexes and photodiode materials, there follows an experimental section (Chapter 2) in which all the experimental details of the various synthetic studies are collected. Chapter 3 deals with the synthesis and characterisation of a range of heterobimetallic complexes of antimony and heavy alkali metals using the stepwise deprotonation of primary amines. Then presented is the first application of the stepwise deprotonation technique to primary phosphines (Chapter 4), demonstrating a direct comparison with heterometallic imido cages. Also presented is the decomposition of the new phosphinidene complex produced into Zintl compounds, providing a low-temperature route to these species. The applications of a heterometallic Sb/Li phopshinidene complex and an Sb/Li Zintl compound to the formation of photosensitive alloys is investigated and measurements show that photoactive materials are accessible via this route. In Chapter 5 the decomposition of phosphinidene complexes into Zintl compounds is probed. The formation of heterocyclic anions of the type [(RP)_nE]^- (E=Sb, As) in various reactions of [E(NMe₂)₃] with [RP(H)Li]_n and [RPH₂] (R=cyclohexyl, tertiary butyl) suggests that Zintl compounds are generated via these species. In Chapter 6 the study shifts its focus to the synthesis of heterometallic As/alkali metal complexes containing [As₂(NCy)₄]^2- anions (Cy=cyclohexyl) and the investigation of the co-ordination chemistry of this species. The theme of ligand synthesis is continued in Chapter 7, where anionic species containing P-P and P-As frameworks are developed.

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23

Hart, I. J. "Synthesis and reactions of some Group 6 metal alkylidyne complexes." Thesis, University of Bristol, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233743.

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24

Cragg-Hine, Ian. "Early main group metal complexes of multi-functional organic molecules." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/271932.

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25

Llewellyn, Susan Clare. "Early main group and mixed-metal complexes of multifunctional amines." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272755.

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26

Blackburn, Octavia Ann. "Synthesis of group 10 metal complexes for potential electronic applications." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/synthesis-of-group-10-metal-complexes-for-potential-electronic-applications(144ae5b9-9bdd-4e74-85d8-24995e3aa50e).html.

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The unique properties of dichroic dyes allow a guest-host display to be fabricated whereby an image is formed by liquid crystal (LC)-assisted orientational changes of the dyes upon application of an electric field. This technology is currently of interest for use in electronic paper, which aims to provide the consumer with the advantages of electronic media whilst enjoying portable paper-like images. Essential to this approach is the availability of chromophores with especially high dichroic ratios (DRs). This thesis concerns the relatively unprecedented use of metal ions in constructing new dichroic dyes. Previous studies have shown that DRs can be augmented by elongation of a dye, which can be facilitated by using metal ions to link simple organic chromophores. Linear connection of azobenzene moieties has been achieved by the synthesis of twenty new N2O2-chelated NiII and PdII complexes, resulting in approximately two-fold elongation. Single crystal X-ray structures have been obtained for two pro-ligands and five complexes, the latter showing strictly square-planar arrangements about the metal centres, except for a NiII complex of a ‘salen-like’ ligand. 1H NMR spectra of NiII complexes display broadening attributed to some distortion from square-planar in solution. UV–visible spectra of the complexes display intense bands in the range 409–434 nm with some metal-to-ligand charge-transfer (MLCT) character, as confirmed through Zerner’s intermediate neglect of differential overlap (ZINDO) and time-dependent density functional theory (TD-DFT) calculations. DR measurements in several LC matrices show that complexation to NiII results in an increased DR whereas PdII appears to have a detrimental effect. Side-by-side connection of azobenzene chromophores yields more intricately shaped complexes which are intended to show improved alignment within an LC through ‘mutual packing’. Eight new chloride-/acetate-bridged dipalladium complexes of push–pull azobenzene ligands have been synthesised. The complexes possess complicated UV–visible spectra, which are interpreted with the aid of TD-DFT calculations. The azobenzene-based band at low energy has superior dichroism to the metal/bridge-based band at higher energy, although no improvement in DR with respect to the pro-ligands is observed. Elongated analogues of these dinuclear systems are provided by three new chloride-bridged tetrapalladium complexes of 1,4-bis[trans-phenylazo]benzenes (BPAB) and an azoazoxybenzene derivative. Single crystal X-ray structures have been obtained for two pro-ligands and one complex, showing severe departures from planarity caused by the methyl groups of the central aryl rings. UV–visible spectra differ for BPAB and azoazoxybenzene complexes, which TD-DFT calculations show is due to charge-transfer character in the latter. DR results follow the same trends as for the dinuclear complexes, and in both cases these results correlate with the TD-DFT-calculated directions of the transition dipole moments (μ12). Six new PtII NCN-pincer complexes of 1,3-bis(N-methylimino)benzene ligands have been synthesised with various 5-substituents. The UV–visible spectra show intense high-energy ILCT bands for aryl- and styryl-substituted complexes with several low energy bands of mixed parentage. Structured emission is observed in solution at room temperature, with quantum yields of 0.1–0.2% and lifetimes of 159–170 ns, except for styryl-substituted complexes where emission is quenched by trans–cis isomerisation. DFT calculations indicate the emission to be of 3LLCT/3MLCT origins. Single crystal X-ray structures of two complexes reveal symmetric planar PtNCN cores with non-ideal N–Pt–N angles, and short intermolecular Pt…Pt distances (3.5469(4) Å) for an unsubstituted complex. Absorption DR results are negligible and measurement of dichroic luminescence is complicated by luminescence of the LC.

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27

Scheibel, Markus. "Metal-Nitrogen Multiple Bonds with Square-Planar Group 9 Transition Metal PNP Pincer Complexes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9944-4.

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28

Clode, Kirsten Everald. "Mono-and dimetallic #PI# - complexes of the group VI metals." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329849.

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29

Jolly, B. S. "Sterically hindered organic complexes of the heavier group 14 elements." Thesis, University of Sussex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383558.

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30

Wu, Chun. "The application of iridium(III) complexes in luminescent sensing and theranostics." HKBU Institutional Repository, 2020. https://repository.hkbu.edu.hk/etd_oa/805.

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The development of transition metal complex-based luminescent probes and theranostic have recently aroused tremendous interest for labelling and detecting environmental contaminants and cellular biomarkers, particularly in the use of real- time diagnosis and treatment of disease. Reasons behind include the unique photophysical properties of transition metal complexes, particularly in the properties of their long-lived and environmentally sensitive emission, which can be easily fine-tuned via the modification of the metal center and auxiliary ligand of the metal complex to achieve the desired emissive characteristics. In Chapter 2, a series of luminescent iridium(III) complexes were introduced and their synthesis and evaluation on their ability to interact with hydroxide (OH- ) ion in semi-aqueous media at ambient temperature were discussed. Upon addition of OH- ion, a nucleophilic aromatic substitution reaction takes place at the bromine groups of the N^N ligand of iridium(III) complex 2.1, resulting in the generation of product with a yellow-green luminescence. Complex 2.1 showed a 35-fold enhancement in emission signal at pH 14 when compared to neutral pH, and the detection limit for OH- ions was found to be 4.96 μM. Complex 2.1 exhibited high sensitivity and selectivity, long-lived luminescence and impressive stability. Additionally, practical application of complex 2.1 was demonstrated to be able to detect OH- ions in simulated wastewater. In Chapter 3, a series of luminescent iridium(III) complexes were introduced and their design and evaluation on their affinity to detect oxalyl chloride ((COCl)2) at ambient temperature were discussed. In the presence of (COCl)2, a double amidation reaction takes place at the diamino functionality of complex 3.1, leading to the switching-on of a long-lived red luminescence with 9-fold enhancement in emission signal. Complex 3.1 exhibited high sensitivity and selectivity and the detection limit for (COCl)2 was found to be 32 nM. Additionally, complex 3.1 can be used to detect (COCl)2 using a simple smartphone, which allows the detection to be a real-time one. iii In Chapter 4, a dual-functional luminescent probe and inhibitor was designed for the in-situ monitoring of neuraminidase (NA) using a structure-based molecular design strategy. The candidate iridium(III) complexes 4.1a-4.1d were synthesized by grafting an oseltamivir moiety as a binding unit onto signaling iridium(III) precursors, generating probes that allowed for the simultaneous inhibition and sensing of NA. Complexes 4.1a-4.1d showed strong yellow or red luminescence in aqueous buffer containing 0.5% acetonitrile in response to NA. In particular, complex 4.1d exhibited enhanced inhibition against NA compared to the FDA-approved antiviral drug, oseltamivir. Moreover, complex 4.1d also displayed a long-lived lifetime, large Stokes shift, and high quantum yield, allowing its luminescence output to be distinguished in the presence of an interfering auto- fluorescent background. We have successfully developed the first dual-functional molecule 4.1d for the in-situ inhibition and detection of NA, which provides the possibility for the in-field simultaneous therapy and monitoring of influenza infection. In Chapter 5, a general strategy was introduced for the development of a long- lifetime iridium(III) theranostic by grafting a well-known inhibitor as a "binding unit" onto an iridium(III) complex precursor as a "signaling unit". To further optimize their emissive properties, the effect of imaging behavior was explored by incorporating different substituents onto the parental "signaling unit". This design concept was validated by a series of tailored iridium(III) theranostic 5.2a-5.2h for the visualization and inhibition of EGFR in living cancer cells. By comprehensively assessing the theranostic potency of 5.2a-5.2h in both in vitro and in cellulo contexts, probe 5.2f containing electron-donating methoxy groups on the "signaling unit" was discovered to be the most promising candidate theranostic with desirable photophysical/chemical properties. Probe 5.2f selectively bound to EGFR in vitro and in cellulo, enabling it to selectively discriminate living EGFR- overexpressing cancer cells from normal cells that express low levels of EGFR with an "always-on" luminescence signal output. In particular, its long-lived lifetime enabled its luminescence signal to be readily distinguished from the interfering iv fluorescence of organic dyes by using time-resolved technique. Complex 5.2f simultaneously visualized and inhibited EGFR in a dose-dependent manner, leading to a reduction in the phosphorylation of downstream proteins ERK and MEK, and inhibition of the activity of downstream transcription factor AP1. Notably, complex 5.2f is comparable to the parental EGFR inhibitor 5.1b, in terms of both inhibitory activity against EGFR and cytotoxicity against EGFR- overexpressing cancer cells. This tailored dual-functional iridium(III) theranostic toolkit provides an alternative strategy for the real-time and personalized diagnosis and treatment of cancers. Chapter 6 discusses the challenges and future inspirations for the development of iridium(III) complex-based luminescent probes and theranostic

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31

Du, Guodong. "Group 4 Metalloporphyrin diolato Complexes and Catalytic Application of Metalloporphyrins and Related Transition Metal Complexes." Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2004. http://www.osti.gov/servlets/purl/835301-irsXCw/webviewable/.

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32

McAslan, Ewan Blyth. "Synthetic, structural and spectroscopic studies on some platinum group metal complexes." Thesis, University of Edinburgh, 1986. http://hdl.handle.net/1842/28560.

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33

Ghaffar, Tallit. "Synthesis, structure and catalytic activity of some platinum group metal complexes." Thesis, King's College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281709.

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34

Burger, M. R. (Marga Retha). "Condensed phase properties of platinum group metal complexes from computational simulations." Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16263.

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Thesis (MSc)--University of Stellenbosch, 2004
ENGLISH ABSTRACT: A variety of computational techniques are used to calculate structural, thermodynamic and transport properties of two specific Platinum Group Metal (PGM) complex systems. The first system consists of a PGM complex ([PdCl4]2-; [PtCl4]2-; [PtCl6]2- or [RhCl6]3-) with sodium counter-ions in a water solution at 30ºC and at a concentration of 0.106 mol/dm3. The second system under consideration is that of a PGM complex ([PdCl4]2-; [PtCl4]2-; [PtCl6]2- or [RhCl6]3-) with sodium counter-ions in a water solution in the presence of four poly (ethylene oxide) (PEO) chains at 30ºC and at a concentration of 0.013 mol/dm3. A conformational study of the two types of dihedral angles in a PEO chain (-C-O-C-Cand -O-C-C-O-) is performed and the extreme flexibility of the polymer is confirmed. Dihedral angle distributions of the two dihedral angles are calculated and explained in terms of the potential energy surface obtained from the conformational study. The solvation geometries of the PGM complexes are confirmed and the results are contrasted with those in the system where the polymer (PEO) is present. It is concluded that the effect of the polymer on the structure and degree of solvation is negligible. The free energy of solvation values of the PGM complexes are calculated to provide insight into their structural characteristics such as solvation shell volume and geometry. The structural and thermodynamic properties of the PGM complexes in solution are also used to explain the trends observed in the calculated diffusion coefficients. Comments are made on the accuracy of the calculated diffusion coefficients as well as the legitimacy of the mechanistic speculations which results from them. Suggestions regarding possible future improvements to the computational methods are made.
AFRIKAANSE OPSOMMING: Verskeie berekenings tegnieke is aangewend om die strukturele, termodinamiese en verplasings eienskappe van twee spesifieke Platinumgroep Metaal (PGM)-kompleks sisteme te bereken. Die eerste sisteem bestaan uit die PGM-kompleks ([PdCl4]2-; [PtCl4]2-; [PtCl6]2- of [RhCl6]3-) met natrium teenione in water by 30ºC en met ‘n konsentrasie van 0.106 mol/dm3. Die tweede sisteem bestaan uit die PGM-kompleks ([PdCl4]2-; [PtCl4]2-; [PtCl6]2- of [RhCl6]3-) met natrium teen-ione in water in die teenwoordigheid van vier poli-etileenoksied (PEO) kettings by 30ºC en met ‘n konsentrasie van 0.013 mol/dm3. ‘n Studie is gemaak van die konformasies van die twee soorte dihedrale-hoeke in ‘n PEOketting (-C-O-C-C- en -O-C-C-O-) en die insense buigbaarheid van die polimeer is hiermee bevestig. Die dihedrale-hoek-verspreidings van die twee tipes dihedrale hoeke is bereken en word verduidelik in terme van die potensiёle energie kromvlakke soos bereken tydens die konformasie analiese. Die geometrie van die solvasie van die PGM-komplekse is bereken en vergelyk met die sisteme waar die polimeer (PEO) teenwoordig is. Hieruit word afgelei dat die effek van die polimeer op die struktuur en graad van solvasie van die komplekse minimal is. Die vrye energie van solvasie van die PGMkomplekse is bereken met die doel om insig in te win oor die stukturele eienskappe soos byvoorbeeld die volume van die solvasie sfeer en die geometrie daarvan. Die strukturele en termodinamiese eienskappe van die PGM-komplekse in oplossing word ook gebruik om die neigings in die berekende diffusie koёffisiente te verduidelik. Opmerkings word gemaak aangaande die akkuraatheid van die berekende diffusie koeffisiente asook die geldigheid van die meganistiese spekulasies wat daaruit gemaak word. Voorstelle word ook gemaak rakende toekomsige verbeterings aan die reken tegnieke.

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35

Bunker, Janet Constance. "The effects of some platinum group metal complexes on bacterial growth." Thesis, Royal Holloway, University of London, 1985. http://repository.royalholloway.ac.uk/items/a0148261-1454-40d1-94dc-bf2b46c26c71/1/.

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Experimental conditions were established which gave reproducible power-time and biomass-time traces for Klebsiella aerogenes growing in glucose-limited medium and Staphylococcus aureus 13137, Ps47 and Pseudomonas aeruginosa in nutrient broth. Aeration of the cultures was critical in determining the shape and reproducibility of the power-time traces. High oxygen tensions caused a reduction in the final biomass value and an increase in waste heat production in nutrient broth. Biomass production occured without any accompanying heat production and vice versa in nutrient broth. The reproducible power-time and biomass-time traces were used to assess the effects of a range of platinum group metal complexes (PGMC) on bacterial metabolism. Several complexes showed anitbacterial activity unlike any other antibacterial agent studied, whilst other complexes had a negligible effect on bacterial growth. Generally complexes were active against either K.aerogenes or S.aureus. Neither organism was able to develop resistance against active complexes. No structure-activity relationships could be established. However, three square-planar palladium complexes, with different ligands, had similar effects on the thermal and growth properties of K.aerogenes. Changes occurring in PGMC solutions with time, monitored spectrophotometrically, reduced antibacterial activity as did interactions between the complex and components of nutrient broth. PGMC solutions had a markedly different effect on bacterial growth when present in the medium before inoculation compared to the effect when the complex was injected in the mid-exponential growth phase. Microcalorimetry is a technique which allows for rapid screening of complexes and continuous monitoring of their effects on bacterial metabolism. The apparent inability of bacteria, even a strain of S.aureus resistant to several antibiotics, to develop resistance against active complexes indicates their potential in clinical applications.

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36

Fujita, Kenichi. "Synthesis, Structure, and Reactivity of Novel Group 8 Transition Metal Complexes." Kyoto University, 1997. http://hdl.handle.net/2433/202318.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第6878号
工博第1629号
新制||工||1070(附属図書館)
15965
UT51-97-H262
京都大学大学院工学研究科物質エネルギー化学専攻
(主査)教授光藤武明, 教授植村榮, 教授玉尾皓平
学位規則第4条第1項該当

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37

Nettles, Shawn M. "Synthesis and characterization of electrophilic group 4 metal complexes of benzynes." Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=175.

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Thesis (M.S.)--West Virginia University, 1998.
Title from document title page. Document formatted into pages; contains vii, 69 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 62-64).

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38

Genge, Anthony Richard John. "Mono- and bi-dentate group 15 and 16 ligand complexes of main group metal halides." Thesis, University of Southampton, 1999. https://eprints.soton.ac.uk/393598/.

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39

Coward, Kathleen Margaret. "Studies into the adduct chemistry of group III and II metal alkyls." Thesis, University of Salford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395743.

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40

Lu, Lihua. "Design and syntheses of Ir(III) complexes as luminescent biosensors." HKBU Institutional Repository, 2015. https://repository.hkbu.edu.hk/etd_oa/276.

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Luminescent transition metal complexes have attracted tremendous interest in the analytical field. Most luminescent metal complexes possess long emission lifetimes in the visible region, and their phosphorescence can be readily distinguished from short-lived background auto-fluorescence. Moreover, their large Stokes shift can prevent self-quenching, while their modular synthesis allows their properties to be readily tuned without labor-intensive synthetic protocols. These properties render transition metal complexes as promising candidates for the development of biosensors. In this study, I aimed to explore different kinds of Ir(III) complexes that can be used as biosensors to monitor DNA secondary structures or protein conformations. Chapter 1 gives a brief introduction regarding the luminescence mechanism of transition metal complexes, and the properties, structures and preparations of Ir(III) complexes are also introduced. Chapters 24 report the syntheses and screening of Ir(III) complexes, and the use of these Ir(III) complexes to monitor the secondary structure of DNA, such as G-quadruplex, G-triplex and i-motif DNA. Chapter 2 reports the G-quadruplex-selective properties of two luminescent Ir(III) complexes 2.1 and 2.9 for the detection of ochratoxin A (OTA) and nicking endonuclease in aqueous solution, respectively; Chapter 3 explores a novel Ir(III) complex 3.8 which is highly specific for G-triplex DNA, and was thus employed for Mung Bean nuclease activity detection; Chapter 4 introduces the Ir(III) complex 4.1 that exhibited a high signal enhancement to i-motif DNA, and was therefore used for terminal deoxynucleotidyl transferase (TdT) activity detection. Chapter 5 describes the two novel cyclometalated Ir(III) complexes 5.1 and 5.21 that were used to monitor two kinds of proteins, human serum albumin (HSA) and beta-amyloid(140) (Aβ140), respectively.

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41

Le, Roux Adele. "Hard-hard and soft-soft coordination in complexes of Group 6 and Group 10 & 11 metals respectively." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/868.

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42

Kamadulski, Andrew. "Design and Synthesis of Mn(III) dipyrromethene Metal Complexes as Peroxynitrite Reduction Catalysts." Thesis, Southern Illinois University at Edwardsville, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10249951.

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Since first being proposed as a biological oxidant in 1990 by Beckman¹, the understanding of peroxynitrite’s role in oxidative and nitroxidative stress has rapidly expanded. Peroxynitrite has been shown to react wide a wide variety of biomolecules through both nitration and oxidation events, causing extensive cellular damage. Physiological and biochemical studies have implicated peroxynitrite in a wide range of disease states including cardiac disease, ischaemia/reperfusion injury, cancer, diabetes, and both inflammatory and neuropathic pain. Clearly, compounds that are capable of scavenging peroxynitrite are highly desirable.

Compounds known to reduce peroxynitrite, primarily Mn(III) and Fe(III) Porphyrin, Corrole and Salen complexes, have been widely described in the literature. Typically these are polycationic complexes which render them highly water soluble and excellent for in vitro laboratory measurements, yet poor candidates for in vivo pharmacology due to poor solubility through the hydrophobic spaces within membranes. In order to develop more ideal drug candidates, with the ultimate goal of oral bioavailability, our group initially synthesized charge shielded, cyclohexyl fused, Mn(III) porphyrin complexes that have demonstrated remarkable results in the animal models of antinociceptive, neuropathic and inflammatory pain, conditions known to be driven by the over production of peroxynitrite. Further investigations by our group have also proven Mn(III) complexes derived from the B,O chelated boron dipyrromethene dyes first reported by Burgess are also highly effective in animal pain models.

The work herein describes the development of Mn(III) complexes of both porphyrins and bis-hydroxyphenyl dipyrromethenes for the use as pharmacological tools in understanding of the role of peroxynitrite in pain and other diseases. A history of porphyrin chemistry and the development of the charge shielded porphyrin scaffold as a synthetic peroxynitrite reductase is given. Design and synthesis of the newly designed Mn(III) bishydroxyphenyl dipyrromethene based complexes is discussed including their advantages over Mn(III) porphyrins. New synthetic work in creating non-cyclohexyl fused analogues of our prototype compounds through a set of orthogonal, Palladium(0) mediated cross-coupling reaction conditions is presented. As the library of catalyst compounds grew a rapid method for the assay of catalytic activity was sought. The development of a novel in vitro chemical assay is demonstrated and its utility in ranking compounds with regards to their peroxynitrite reductase activity, as well as estimating the 2^nd order rate constants is also illustrated.

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43

Jones, Simon C. "Metal-metal coupling in bi- and multimetallic systems : organometallic pentalene and group 14-bridged cyclopentadienyl complexes of transition metals." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270635.

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44

Wicks, Joseph Leslie Michael. "Routes to mixed metal compounds of the platinum group : metal σ-acetylide complexes and platinum clusters." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620495.

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45

Kristofzski, John Gregory. "Ionization-structure relationships of thin film and gas phase group VI metal-metal quadruple-bonded complexes." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184384.

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Principles involving the electronic structure of group VI metal-metal multiple bonded complexes are examined in order to provide insights into the intramolecular and intermolecular interactions of these systems. Examination of chromium, molybdenum and tungsten tetracarboxylate thin films by ultraviolet photoelectron spectroscopy has provided the first experimental evidence for the location of the σ ionization in dimolybdenum tetracarboxylate quadruple bonded complexes. These compounds have significant intermolecular interactions as thin films which destabilizes ionization of the valence σ state, allowing it to be experimentally observed. This is supported by the observed destabilization of the σ ionization feature of the ditungsten analogue in going to the thin film. The Cr₂(O₂CCH₃)₄ comparison shows a destabilization of the leading predominantly metal ionizations consistent with the broad range of M-M bond lengths observed for Cr₂ complexes. The Group VI M₂(mhp)₄ and M₂(chp)₄ [mhp=6-methyl-2-oxo-pyridine and chp=6-chloro-2-oxo-pyridine] complexes are also examined. The geometric constraints imposed on the compounds by the ligand effectively block intermolecular interaction axial to the metal-metal bond in the solid state. Comparison of the two ligand spectra, Hmhp and Hchp, has provided a unique opportunity to assign ionizations previously attributed to the keto form of the Hmhp tautomers. The spectra of the complexes exhibit minimal relative shifting of ionization features in going to the thin films because of this constraint. A band previously believed to be due to spin orbit coupling is assigned to the σ ionization in the ditungsten complex. The overall ionization band profiles of the two series correlate well, metal by metal, with the expected shifting due to substitution of the more electronegative chlorine atoms for a methyl group. The synthesis and characterization of Mo₂(N-t-butyl-acetamide)₄, the first tetraamidodimetal compound without large rings with delocalized pi structure, is described. The single crystal X-ray structure is presented, revealing the novel (one of three examples) cis configuration of the MoN₂O₂ ligand set. The Mo-Mo bond length of 2.063 Å is one of the shortest seen to date. A preliminary gas phase He I valence spectrum is reported.

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46

Halepoto, Dost Muhammad. "Syntheses and structures of some novel chromium(II), vanadium(II) and vanadium(III) complexes." Thesis, University of Surrey, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375971.

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47

Parkin, Christopher James. "The structure and co-ordination chemistry of group 2 metal salicylate complexes." Thesis, University of Hull, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417162.

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48

Bartlett, Ian Mark. "The redox activiation of alkyne ligands in group 6 transition metal complexes." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390376.

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49

Hawkes, Kirsty June. "Group 9 and 10 transition metal n-heterocyclic carbene complexes in catalysis." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/56061/.

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This thesis describes the theoretical and experimental study of group 9 and 10 transition metal N-heterocyclic carbene complexes in catalytic reactions. In order to overcome decomposition reactions discovered in the use of carbene complexes for carbon monoxide/ethylene copolymerisation, chelating thiazolium salts were prepared for the synthesis of corresponding palladium complexes. Complex formation proved difficult and experimental attempts to overcome possible side reactions caused by reactant-metal interactions were unsuccessful. Theoretical studies indicated a sulfur-palladium interaction may be contributing to alternative products, with the use of the bulky lBu coordination at the thiazolium 5 position likely to block this interaction enough to allow C2 carbene formation. Theoretical calculations for the oxidative addition of azolium salts to a model Wilkinson's catalyst (RhCl(PH3)3) is described. According to free energy calculations, a six ligand associative route with a concerted three-centred transition structure may be competitive to a route in which phosphine predissociation occurs. Exchange of the phosphine molecule on the metal centre with trimethylphosphine had a significant effect in lowering the barrier to oxidative addition and decreasing the endothermicity of the reaction, while explicit and bulk solvation was found to have a moderate effect on the overall reaction. Extension of the oxidative addition of azolium salts to rhodium carbene complexes have been examined, in which a range of ligands is described from the pi-acidic carbon monoxide ligand to multiple carbene ligands. Increasing basicity decreases activation barriers while increasing the exothermicity of the overall reaction for C-H activation, however the complex most successful at C-H activation was not considered hospitable enough for related C-C activation of 2-methylazolium salts. Switching to iridium indicated a large benefit in C-H activation. Unfortunately, C-C activation remained unfavourable for iridium due to a high barrier to reaction. A mechanism for the experimentally successful C-C coupling of azolium salts to alkenes by nickel complexes is studied, indicating an oxidative addition, alkene insertion and reductive elimination cycle seems likely. Experimentally, the switching of catalytically active phosphine ligands to the related carbenes causes the reaction to be halted. Theoretical calculations imply minor changes to reaction conditions may significantly affect the outcome of catalytic reactions by stabilisation of important reaction intermediates. Further studies of the alternative C4 activation of the azolium salts and use of related azoles show C4 activation and coupling may be possible, while the unactivated azoles are unlikely to be coupled using the same mechanism. (Abstract shortened by UMI.)

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50

Burgoyne, Andrew R. "Development, synthesis and anticancer evaluation of trinuclear Platinum Group Metal organometallic complexes." Doctoral thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20303.

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Over the past few decades metals in medicine have played to play a significant role, especially after the discovery of the anticancer properties of cisplatin. However, acquired and intrinsic resistance, toxicity and a host of side-effects have encouraged the research for new metal based anticancer agents. Organometallic complexes have proved to be successful anticancer agents and several have commenced clinical trials. The aim of this study was to prepare and characterize trinuclear platinum group organometallic complexes and investigate their in vitro activity. The first series of ester containing complexes were prepared. The ligands were generated by the preparation of Schiff base ligands obtained from the condensation of 4-aminophenylmethanol and either benzaldehyde, 2-pyridinecarboxaldehyde or salicylaldehyde. Trimeric ester ligands were prepared from these monomeric ligands by reaction with trimesoyl chloride.

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Dissertations / Theses on the topic 'Group III metal complexes'

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