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1
Cheung, Wai Man. "Transition metal complexes with dichalcogenoimidodiphosphinate ligands /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202007%20CHEUNG.
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Skinner, Michael E. G. "Transition metal complexes of diamide-diamine ligands." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365390.
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Seidel, Scott William 1971. "Transition metal complexes containing chelating amido ligands." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47411.
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Olson, Michael David. "Pyrazolyl based ligands in transition metal complexes." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/27610.
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Several uninegative/ multidentate pyrazolyl based ligands were synthesized [eg. HBPZ₃₋, HBpz”₃₋, MeGapz₃₋/ MeGapz” ₃₋, H2BpZ₂₋/ Me2Bpz₂₋/ Me2GapZ₂₋/ Me2Gapz"₂₋/ Me₂Gapz(OCH₂CH₂NH₂)⁻Me₂Gapz(OCH₂CH₂CH=CH₂)⁻ ; pz pyrazolyl/ pz" = 3, 5 dimethylpyrazolyl].
These ligands were reacted with the sterically hindered metal complex, HBpz*₃MCl (M = Co, Ni; pz* = 3-iPr-4-Br-pyrazolyl) and the mixed-ligand transition metal complexes of general formulae, HBpz*₃ML, were isolated. The X-ray crystal structure of one such complex, HBpz*₃Nipz"₃BH was determined showing a near octahedral arrangement of ligands about the nickel centre. The electronic spectra of the nickel complexes were recorded and compared to predicted transitions. The electronic spectra of the four coordinate nickel complex, HBpz*₃NiCl, fit a d⁸, tetrahedral, ligand field model. The six coordinate complexes, HBpz*₃NiL (L = HBPZ₃, HBpz"₃, MeGapz₃, MeGapz”₃), fit a d⁸, octahedral, ligand field model.
The unsymmetrical pyrazolylgallate ligands were reacted with the rhodium dimer [Rh(CO)₂CI]₂ to give the square planar complexes, LRh(CO) [L = Me2Gapz(OCH₂CH₂NH₂), Me₂Gapz(OCH₂CH₂CH=CH₂)]. These rhodium[I] complexes appeared to undergo oxidative additions of Mel, allylbromide and I₂. Furthermore these rhodium[I] complexes appeared to bind the small gas molecules, CO and ethene.
A number of heterobimetallic complexes, with direct metal-metal bonds, were prepared and isolated from the reaction of the molybdenum anion, HBpz"₃(CO)₃MO⁻ with the transition metal halides, [CuPPb₃Cl]₄, SnR₃Cl (R = Me, Ph) and GePh₃Cl.Science, Faculty of
Chemistry, Department of
Graduate
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Lawrence, Sally. "Early transition metal complexes of pyrazole-derived ligands." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433560.
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Franks, Mark A. "Transition metal complexes containing phenylthiolate and phenolate ligands." Thesis, University of Nottingham, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580393.
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Chapter 1 provides an introduction to metalloenzymes that either feature active sites containing Ni-thiolate ligation or utilise phenoxyl radicals to perform their catalytic function, with a particular emphasis on the enzymatic active sites of Ni-containing superoxide dismutase (Ni SOD), [NiFe] hydrogenase and galactose oxidase. Studies concerning low molecular weight complexes of each active site are reviewed and their relevance with respect to enzyme function discussed. Details of the project outline conclude the chapter. Chapter 2 details the syntheses and characterisation of the [Zn(tsalen)] derived complexes [ZneBuLsC3N)], [ZneBuLsC2N)], [ZneBuLsNMe)], [ZneBuLlyl)], [Zn(IBuLsPy2)], [ZneBuLsPhl)], [Zn(IBuLslml)2], [ZneBuLsPy3)2], [Zn(LsC2N)], [Zn(LsNMe)], [Zn(Llyl)], [Zn(LsPy2)] and [Zn(LsPh1)], via Zn(II) templated Schiff- base condensation reactions using two thiosalicylaldehyde derived units and a range of primary amines. The syntheses of 2,4-di-tert-butyl-thiosalicylaldehyde from tert- butyl benzene and three functionalised 1,3-propyldiamines (2-(2-pyridylmethyl)-1,3- propanediamine, 2-(2-pyridylethyl)-I,3-propanediamine and 2-benzyl-I,3- propanediamine) are described. X-ray crystallographic studies demonstrate the successful integration of the additional N-donors into the backbone of the ligand framework at the N-imine position. The range of S2N2, S2N3 and S2N4 ligand sets are shown to adopt an array of coordination geometries about the Zn(II) metal centre providing scope for these ligands in tuning the electronic structures of their Ni- containing complexes. Chapter 3 describes the syntheses and X-ray crystallographic, electrochemical and spectroscopic studies of a series of Ni(II) Schiff-base dithiolate complexes, [Ni(IBuLsC3N)], [Ni(IBuLsc2N)], [NieBuLsNMe)], [NieBuLlyl)], [Ni(IBuLly2)], III [Ni(BuLlhl)], [Ni(BuLs1ml)2], [Ni(tBuLly3h]' [Ni(LsPyl)], [Ni(LsPY2)] and [Ni(LsPhl)] obtained via transmetallation from the analogous [Zn(BuLl)] and [Zn(LsR)] complexes described in Chapter 2. The effect that the additional pendant N-donors have upon the redox properties of the individual complexes are considered with respect to reproducing the structural, spectroscopic and functional properties of NiSOD. Particular attention is focussed on the redox properties of [Ni(BuLsPyl)], [Ni(tBuLsPy2)] and [Ni(BuLsPhl)], which together highlight a rare example of the ability of one N-donor group to assume the role of an endogenous donor upon oxidation. The proposed internal rearrangement of the Ni coordination sphere may encourage the formation of a predominantly metal-based SOMO following the oxidation process. Insight upon how this coordination chemistry relates to the chemistry of the active site of Ni SOD is discussed. Chapter 4 reports the electrochemical and spectroscopic characterisation of a range of binuclear [Ni(LsR)Fe(CO)3] and trinuclear [Ni(LsR){Fe(CO)3h] complexes (R = PhI, PyI and Me) synthesised via the reaction of [Ni(tsalen)]-type complexes, [Ni(LsR)], with Fe2(CO)9. X-ray crystallographic studies show that the complexes incorporate biologically relevant structural elements reminiscent of the active site of [NiFe] hydrogenase, including a binuclear Ni(1l2-S)Fe core featuring a ea. 2.9 A Ni- Fe separation. Chapter 5 details the preparation of a series of Zn(II), Ni(lI) and Cu(lI) Schiff-base diphenolate complexes utilising the two novel pentadentate pro-ligands, [H2tBuLo C3N] and [H2tBuLo NMe]. Cyclic voltammetric, spectroelectrochemical and EPR studies show the Zn(lI) and Cu(lI) complexes support two ligand-based oxidation processes, yielding kinetically inert species possessing phenoxyl radical character. Conversely, the paramagnetic Ni(lI) complexes, [Ni(BuLo NMe)] and IV [Ni(tBuLo C3N)], support both metal and ligand-based oxidation chemistry. The chapter concludes by discussing the relative stability of phenoxyl and phenylthiyl radical ligands by comparison with the redox properties of the analogous Schiff-base Zn(II)-dithiolate complexes described in Chapter 2.
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Rivers, Christopher John. "Transition metal complexes incorporating trialkylsilyl substituted pentalene ligands." Thesis, University of Sussex, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289228.
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Herring, A. M. "New transition metal complexes containing functionalised phosphine ligands." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383967.
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Ivison, Peter. "Transition metal complexes of hard-soft donor ligands." Thesis, Kingston University, 1992. http://eprints.kingston.ac.uk/20562/.
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Ghebregziabiher, Berhe Haile. "Synthesis of chiral thiourea ligands and their transition metal complexes." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53610.
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Thesis (MSc)--Stellenbosch University, 2003.ENGLISH ABSTRACT: Modification of chitosan with benzoylisothiocyanate was attempted, however due to solvent problem the study was left incomplete till appropriate solvent is designed. N,N-diethyl-N -camphanoylthiourea (HL8), N-piperidyl-N '-camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthiourea (HL10) and N,N-diethyl-N -adamantylcarbonyl thiourea (HL11)have been synthesised and characterised for the first time. Two of these ligands HL8 and HL11, were used to form a number of transition metal complexes, namely H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], translcis-[Zn(L 8_S,0)2], translcis-[Pt(L 8_S,0)2], Ag2[(HL8-S)(L-J.1-S,O)]2, translcis- [Ni(L11-S,O)2]and translcis-[Cu(L11_S,O)2]. The new products are fully characterised by means of MS, IR spectroscopy, NMR spectroscopy, elemental (C, H, Nand S) analysis and melting point determinations. The H30+{fae-[Co(L8-S,Obn, cis-[Ni(L8- S,O)2], trans-[Cu(L8-S,O)2] and Ag2[(HL8-S)(L-J.1-S,O)]2 are also characterised by Xray diffraction analysis. The structure of the new chiral N,N-dialkyl-N' -camphanoylthiourea ligand (HL8) has a significant effect on its coordination chemistry with transition metal ions. This ligand forms H30+ {fae-[Co(L8-S,Obn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,O)2] and Ag2[(HL8- S)(L8-J.1-S,O)]2 complexes with the Co(II), Ni(II), Cu(II) and Ag(I) metal ions respectively. The spectroscopic and X-ray diffraction results of these complexes indicate a bidentate mode of coordination of the ligand (with its Sand °donor atoms) to the Co(II), Ni(II) and Cu(II) metal ions. The reaction of this ligand with silver(I) however affords the formation of a binuclear silver(I) complex exhibiting monodentate and bidentate modes of coordination within the same complex. The exclusive formation of trans-[Cu(L8-S,0)2] is a new phenomenon for the HL type thiourea ligands with Sand °donor atoms. Up to this point a maximum of 15 % trans-isomer has been reported in ltterature." All the transition metal complexes made with HL8and HL11are air stable in both the liquid and solid states except the H30+{fae-[Co(L 8-S,Ob]} Interestingly the deep green fae- H30+{fae-[Co(L8-S,Obn complex is air sensitive and the Co(II) oxidizes to Co(III) in the complex by atmospheric O2. The oxidation of Co(II) to Co(III) in the complex is confirmed by 1Hand 13CNMR spectra as well as by UV-Visible spectra of the complex. The NMR spectra of the complexes indicated the presence of one isomer in each complex except for the NMR spectra of the platinum complex of the HL8 ligand. The presence of the minor trans-[Pt(L8-S,Q)21 isomer in combination with the major cis-[Pt(L8-S,Q)21 isomer in the platinum complex was indicated by the 1H, 13Cand 195ptNMR spectra of the complex.
AFRIKAANSE OPSOMMING: Pogings om chitosan met benzoylisothiocyanate te modifiseer is onvoltooid gelaat weens die gebrek aan'n geskikte oplosmiddel. N,N-diethyl-N -carnphanoylthiourea (HL8), N-piperidyl-N -camphanoylthiourea (HL9), N-pyrrolidyl-N -camphanoylthlourea (HL10) en N,N-diethyl-N -adamantylcarbonyl thiourea (HL11) is vir die eerste keer gesintetiseer en gekarakteriseer. Twee van die ligande, HL8 en HL11, is gebruik om verskeie oorgangsmetaalkomplekse te berei, nl. H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L8-S,0)2], trans/cis-[Zn(L8 - S,0)2], trans/cis-[Pt(L8-S,0)2], Ag2[(HLB-S)(L-jl-S,0)]2, trans/cis-[Ni(L11-S,0)2] en trans/cis-[Cu(L11_S,0)2]. Die nuwe produkte is volledig gekarakteriseer deur middel van MS, IR spektroskopie, KMR spektrometrie, elemente (C, H, N en S) analise en smeltpuntbepaling. Die komplekse H30+{fao-[Co(L8-S,0)3n, cis-[Ni(L8-S,0)2], trans- [Cu(L8-S,0)2] en Ag2[(HLB-S)(L-jl-S,0)]2 is ook deur middel van X-straaldiffraksieanalise gekarakteriseer. Die struktuur van die nuwe chirale N,N-dialkyl-N'-camphanoylthiourea ligand (HL8) het In beduidende invloed op die koordinasie van hierdie ligand met oorgangsmetaalione. Die ligand vorm H30+{fac-[Co(L8-S,Ohn, cis-[Ni(L8-S,0)2], trans-[Cu(L-S,0)2] en Ag2[(HL8-S)(L8-Il-S,0)]2 komplekse met Co(ll)-, Ni(II)-, Cu(II)- en Ag(I)-ione respektiewelik. Spektroskopiese en X-straaldiffraksie-analise van die komplekse toon dat die ligande op 'n bidentate wyse d.m.v. die S- en O-donoratome met Co(II), Ni(lI) en Cu(lI) koordineer. Die reaksie van hierdie ligand met Ag(I)-ione lei egter tot die vorming van 'n dikernige silwer(I)-kompleks waarin die ligande monodentaat (S) en bidentaat (S en 0) aan die metaal gebind is. Die vorming van uitsluitlik die trans-[Cu(L8-S,0)2] in die reaksie van HL8 met Cu(lI) is 'n besondere fenomeen in die chemie van hierdie tipe ligande; in die literatuur word melding gemaak van slegs een ander trans-kompleks met hierdie ligande, en dan wel met 'n maksimum opbrengs van 15%.29 Alle oorgangsmetaalkomplekse met HLB en HL11 is stabiel indien blootgestel aan lug, ongeag of die verbindings opgelos word of in die vastetoestand verkeer, behalwe H30+{fao-[Co(L8-S,Ohn. Die diep-groen gekleurde H30+{fao-[Co(L8-S,Ohn)3]} kompleks is lugsensitief; Co(lI) word deur lugsuurstof na Co(lIl) ge-oksideer. Die oksidasie in die kompleks kan deur middel van 1H en 13CKMR spektrometrie sowel as UV-sigbare spektrofotometrie bevestig word. Die KMR spektra van alle komplekse dui op die teenwoordigheid van slegs een isomeer in oplossing, behalwe in die geval van die platinum(lI) kompleks met HL8. Die teenwoordigheid van lae konsentrasies trans-[Pt(L8-S,0)2] isomeer tesame met veel hoër konsentrasies van die cis-[Pt(L8 -S,O)2] isomeer word deur 1H, 13Cen 195ptKMR spektroskopie aangedui.
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Hawkins, I. M. "New transition metal complexes containing phosphine and sulphur ligands." Thesis, University of East Anglia, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235225.
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Wilson, Paul John. "Early transition metal imido complexes supported by heterocyclic ligands." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285593.
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Chung, Simon S. M. "Transition metal complexes of new mixed donor tridentate ligands." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367415.
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Forder, Robin James. "Transition metal complexes of phosphine and mixed phosphathia ligands." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243129.
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Hayashi, Akito. "Studies of late transition metal complexes bearing phosphaalkene ligands." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136303.
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Zhang, Lilu. "Synthesis and chemistry of lanthanide complexes with phosphorus ylides, amides or porphyrinate ligands, and of transition metal complexes with polydentate ligands." HKBU Institutional Repository, 1999. http://repository.hkbu.edu.hk/etd_ra/182.
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Johnson, Donald Martin. "Cyanoscorpionates and Transition Metal Complexes." Digital Commons @ East Tennessee State University, 2010. https://dc.etsu.edu/etd/1725.
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The new dihydrobis(4-cyano-3-tert-butylpyrazolylborate) ligand has been synthesized. Isolated crystals of the thallium complex were collected and structurally characterized by X-ray diffraction. Transition metal complexes of the ligand are currently under investigation.
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Chi-Tien, Chen. "Transition metal amidinate complexes as new catalysts for olefin polymerisation." Thesis, University of Oxford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365820.
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Organtzis, Stefanos. "Polynuclear transition metal complexes containing azido and pyrazolinato bridging ligands." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496513.
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Following the discovery that a single molecule can behave as a magnet, the field of research on magnetism has become of great interest to scientists. A large number of polynuclear compounds have been produced and studied worldwide over the past two decades, in an effort to obtain better single molecule magnets (SMMs). The synthesis of such compounds involves mainly first row transition metals and a wide range of bridging ligands.
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Potts, Storm Victoria. "Structural analysis of transition metal complexes of imidazole-derived ligands." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2261.
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Duckmanton, Paul Andrew. "Anion-binding ureaphosphine ligands and their late transition metal complexes." Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438264.
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Lu, Canzhong. "Novel transition metal complexes of sterically hindered silyl thiolate ligands." Thesis, University of Essex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307857.
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Hill, Angela M. "Synthesis and studies on transition metal complexes of antimony ligands." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241988.
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Smith, Charles J. "Transition metal complexes on novel, polydentate, water-soluble, phosphine ligands /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841335.
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Jarvis, Amanda G. "Multidentate phosphino-alkene ligands and their late transition metal complexes." Thesis, University of York, 2011. http://etheses.whiterose.ac.uk/1573/.
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The synthesis and characterisation of a new class of multidentate conformationally flexible phosphino-alkene ligands, called dbaPHOS (127) and monodbaPHOS (128), are described is this PhD thesis. The related phosphine sulphide ligands, namely dbaTHIOPHOS (137) and monodbaTHIOPHOS (149), have also been prepared. The coordination chemistry of the novel ligands was investigated with a variety of late-transition metals, including Cu, Rh, Pd and Pt. X-ray crystal structure determination of the complexes containing these ligands highlights the multiple coordination modes and versatility of each ligand system. The ability of the 1,4-dien-3-one backbone to adopt different conformational geometries around metal centers is of particular note. DbaPHOS (127) was found to act as a cis- and trans-chelating bisphosphine in both square planar PdII and PtII complexes. The 1,4-dien-3-one motif is hemilabile; exchange between coordinated and non-coordinated alkenes is observed in both the Pd0 complex, 167, and the related cationic CuI complex, 193. An investigation into the CuI complexes’ activity in the cyclopropanation of styrene, as catalysts, showed that they are commensurate with other recently reported systems. In addition to the coordination chemistry of the novel ligand systems, some interesting findings emerged in the ligand synthesis and characterisation studies. For example, monodbaTHIOPHOS (149) undergoes an interesting solid-state [2+2] intramolecular cycloaddition transformation, giving cycloadduct, 206. Furthermore, 2-hydroperoxytetrahydrofuran was found to be an impurity in the microwave-assisted Horner-Wadsworth-Emmons reaction of 2-(diphenylthiophosphine)benzaldehyde (136) with 1,3-bis-(ethoxyphosphonato)-acetone (130) to give of dbaTHIOPHOS (137) and an unexpected THF insertion product, 138. The latter is explained by a side reaction involving the reduced compound, tetrahydrofuran-2-ol, derived from 2-hydroperoxytetrahydrofuran.
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Hagiwara, Jun. "A Study on Transition Metal Complexes with Redox-active Ligands." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120931.
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Holland, Stephanie. "Synthesis, characterisation and transition metal complexes of nitrogen-containing ligands." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/8162.
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Hamilton, Ewan J. M. "Mono- and dianionic carbaborane ligands and their transition metal complexes." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/14970.
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Chapter 1 consists of a brief overview of transition metal cyclopentadienyl chemistry and of the chemistry of carbametallaborane species derived from [7,8-nido-C2B9H11]2-, with specific reference to the bonding modes commonly adopted by each ligand to transition metal fragments. The forms of the π-MO's of [C_5H_5]^-, [C_2B_9H_11]^2- and of the monoanionic ligand [9-SMe_2-7,8-C_2B_9H_10]^- (or [carb']^-), as obtained by extended Huckel molecular orbital (EHMO) calculations, are also presented. In Chapter 2, the structure of [7,8-C_2B_9H_12]^-, (1), is presented, showing an endo -H atom, rather than the commonly accepted μ-H, associated with the open ligand face. This result is supported by those of n.m.r. and theoretical studies. Isolobal replacement of the endo-terminal hydrogen atom by a (PPh3Au+ ) fragment leads to complex (2), [10-endo-(PPh3Au)-7,8-nido-C2B9H11]-, which has also been studied crystallographically. Structural trends within the series (1), (2) and [PPh3 Cu(C2B9H11)]- have been rationalised via the results of EHMO calculations. Chapter 3 presents the structure of [10,11-μ-H-9-SMe_2-7,8-nido-C_2B_9H_10], (3), the protonated precursor to the monoanionic ligand [carb']^-. The molecule possesses an asymmetric bridging H atom on its open face, a structural feature whose origin may be traced using MO calculations at the extended Huckel level. The (triphenylphosphine)gold(I) and (triphenylphosphine)copper(I) derivatives of [carb']^-, (4) and (5), have been prepared, and their structures determined by X-ray methods. In all three compounds, the SMe_2 substituent appears to adopt a preferred conformation, and it is suggested that this is allied to an intramolecular electrostatic interaction. Analysis of structural patterns within (3), (4) and (5) reveals different trends to those observed for the related series in the previous chapter. These differences may be rationalised by frontier MO considerations.
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Hightower, Sean E. "Preparative and computational studies of metal complexes containing molecular cages." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1400962461&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Green, Simon Michael. "The synthesis and application of novel chiral transition metal complexes." Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285879.
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Reinhardt, Maxwell James. "Metal complexes containing non-innocent ligands for functional materials." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/11723.
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The existence of complexes of that display non-innocence has been of interest in the field of coordination chemistry since the investigations of square-planar dithiolene complexes of the late transition metals in the 1960s. The ligands used in these systems are termed “non-innocent” when bound to a number of the late transition metals, because the orbital energy levels are similar to those of the central metal ion. This allows there to be significant electron delocalisation over the complex with the potential for the complexes to exist in a number of electronic states due to the combined electrochemical activity. In 1966, Jørgensen classified innocence as ligands that “allow oxidation states of the central atoms to be defined”, thus by this logic non-innocent ligands are defined as complexes where the precise oxidation states of the ligand and metal are ambiguously assigned. However it should be noted that no ligand is inherently non-innocent, but rather the ligand may behave in a non-innocent manner under the right circumstances. The qualification of non-innocence should therefore only be applied to combinations of metal and ligand that result in the aforementioned properties. In this thesis, the term “non-innocent” will be used to define ligands that often possess non-innocent behaviour when complexed to the metal centres they are bound to. A general form of ligand that displays non-innocent behaviour is that of the 1,2-bidentate moiety with an unsaturated carbon backbone. The chelating donor groups (X) are either O, NH, S, or a combination of the three. The central transition metal is generally a late metal that favours a square-planar geometry, because the planarity of the complex is crucial for electron delocalisation within the molecule and molecular interactions in the solid material. When the metal is nickel or platinum for example, their square-planar complexes with such ligands have shown threemembered electron-transfer series. Specific examples of ligands that have been shown to display non-innocent behaviour are those of catechol (1,2-dihydroxybenzene) and 1,2-diaminobenzene, where the unsaturated backbone is provided by a phenyl group. The electronic nature of these compounds has been extensively investigated by the groups of Pierpont and Lever, with focus on their redox and magnetic properties. The combined metal and ligand redox activity results in interesting magnetic behaviour, with potential for magnetic exchange interactions between a paramagnetic metal centre and the radical ligand or between two radical ligands mediated by a diamagnetic metal centre. This research has been advanced by Wieghardt and co-workers who have performed experimental and theoretical examination of non-innocent complexes of 1,2-substituted phenyl chelates, where the donor group is a combination of O and NH. These studies have focused on the understanding the nature of the metal-ligand interactions to apply to biological systems, such as those observed at the active site of enzymes that act upon molecules with similar moieties to the non-innocent ligands. Compounds of catechol may be referred to as dioxolenes in analogy to the sulfur-based dithiolenes. The deprotonated, dianionic form of catechol is known as catecholate (cat), which can be readily oxidised to the monoanionic o-semiquinone (SQ) and neutral o-benzoquinone (Q) forms. It has been seen that catecholate compounds can be described by localised electronic states with defined oxidation states, unlike many of the dithiolene class of molecules. However these states can exist in equilibrium with each other when the metal and ligand orbitals are close in energy, with differences in the charge and spin definition in what has been described as “valence tautomerism”. Therefore, although the complexes may not be seen as non-innocent by definition that their oxidation states are not ambiguous, it is still a useful description due to the potential for easily accessible charge states. Metal dithiolene complexes, where the metal is coordinated by one or more ligands with two S-donor atoms linked by a conjugated backbone, are one of the best researched of the non-innocent class of molecules. The square-planar bis-dithiolenes of the late transition metals have interesting magnetic, optical and electrical properties arising from the delocalised nature of the constituent metal and ligand orbitals, which has enabled their use for a wide range of applications such as non-linear optics, transistors and near-infrared switches. Of particular interest is the ability to fine tune the electrical properties to fit the application by changing the substituents on the core dithiolene moiety. For example, Anthopoulos has shown that by lowering the energy of the lowest unoccupied molecular orbital (LUMO), stable n-channel conductivity can be observed in field-effect transistors (FETs). Materials based on square-planar non-innocent complexes have been tested in FETs, and been seen to display field-effect mobilities as high as 10˗2 cm2 V˗1 s˗1 as with Ni bis(o-diiminobenzo-semiquinonate) complexes. Most of these molecules are based on conjugated, chelating ligands such as 1,2-diaminobenzene and the dithiolene class of molecules. Field-effects have also been observed in square-planar Pt complexes, where the conductivity is thought to arise from beneficial Pt-Pt bonds in addition to the π-stacking between molecules. Despite the similarity to the diaminobenzene and dithiolene counterpart, there are no reports of catechol-based materials displaying field-effect properties in the literature. Catechol compounds are well-researched in the field of biological chemistry due to the prevalence of the catechol moiety and enzymes with which it interacts in nature. However they have not been examined far beyond their simple coordination chemistry or chemical characterisation.
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He, Fan. "Transition metal complexes with N-heterocyclic carbene ligands : synthesis and reactivity." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF031/document.
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L’objectif de ce travail est la synthèse de complexes contenant des ligands NHC protiques fonctionnalisés avec un groupement imine dans le but de développer des méthodologies de synthèse donnant accès à des ligands pNHC ainsi que la synthèse des groupes imidazolide anioniques liés par le C et leurs complexes homo et hétéro-dinucléaires. Dans le cas des imidazoles sans groupe fonctionnel, la déprotonation à l’aide de n-butyl lithium a permis l’obtention de (1-aryl-1H-imidazol-2-yl)lithium avec de bons rendements. La réaction de (1-aryl-1H-imidazol-2-yl)lithium avec [Ir(cod)(μ-Cl)]2 ou [Rh(cod)(μ-Cl)]2 a conduit à des complexes dinucléaires bipontés en C2,N3. Dans le cas de l’imidazole possédant une fonctionnalité imine, le complexe de l’Ir(I) lié au N de l’imidazole peut se tautomériser en complexe de l’Ir(I) imine avec un ligand pNHC suite à la réaction d’abstraction du chlorure à température ambiante, alors que la tautomérisation de l’analogue du Rh(I) nécessite une température de 110°C. La déprotonation des complexes de l’Ir(I) et Rh(I) liés par le N de l’imidazole avec addition de [Ir(cod)(μ-Cl)]2 ou de [Rh(cod)(μ-Cl)]2 in situ permet l’obtention de complexes homo et hétéro-dinucléaires. La métallation des sels d’imidazolium fonctionnalisés avec un groupement imine s’est avére être une méthode efficace pour la synthèse de complexes métallés ayant un ligand pNHC et a été étendue des complexes bidentes aux complexes chélatants pNHCThe purpose of this work is the synthesis of complexes containing imine-functionalized protic NHC ligands in order to further develop synthetic methodologies giving access to pNHC, C-bound ‘anionic’ imidazolide, and homo- and heterodinuclear complexes. In the case of imidazoles without functional group, deprotonation with n-butyl lithium afforded (1-aryl-1H-imidazol-2-yl)lithium in good yield. Reaction of (1-aryl-1H-imidazol-2-yl)lithium with [Ir(cod)(μ-Cl)]2 or [Rh(cod)(μ-Cl)]2 yielded a doubly C2,N3-bridged dinuclear complex. In the case of imine-functionalized imidazole, the Ir(I) N-bound imidazole complex can tautomerize to Ir(I) imine-functionalized pNHC complex chloride abstraction at room temperature, while in the Rh(I) analog the tautomerization can be achieved at 110 °C. In situ deprotonation of the N-bound imidazole Ir(I) or Rh(I) complexes, followed by addition of [Ir(cod)(μ-Cl)]2 or [Rh(cod)(μ-Cl)]2 led to the isolation of homo- and heterodinuclear complexes. The metalation of imine-functionalized imidazolium salts is also an effective procedure for synthesis of pNHC metal complexes, and it was extended from bidentate to pincer-type pNHC complexes
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Cordes, David B., and n/a. "Supramolecular transition metal architectures." University of Otago. Chemistry Department, 2005. http://adt.otago.ac.nz./public/adt-NZDU20060705.144929.
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This thesis describes the investigation of the coordination and supramolecular chemistry of three different types of pyridine-containing ligand with a selection of Ag(I), Cu(I), Cu(II) and Cd(II) salts. The ligand types are flexible and four-armed, rigid and four-armed and bent with two rigid arms. All the ligands also display the ability to form additional supramolecular interactions.
Chapter one introduces supramolecular chemistry and crystal engineering and covers background on several areas of current interest in these fields. Network structures, both coordination polymers and hydrogen-bonded systems, are discussed and topological analysis as a method of describing and comparing network structures is introduced. An outline of the ligand design, choice of transition metals and anions is given.
Chapter two provides a review of flexible four-armed pyridine-containing ligands and their use in coordination chemistry. The synthesis and characterisation of three flexible four-armed ligands 1,2,4,5-tetrakis(2-pyridylmethyl-sulfanylmethyl)benzene (2tet), 1,2,4,5-tetrakis(3-pyridylmethyl-sulfanylmethyl)benzene (3tet) and 1,2,4,5-tetrakis(4-pyridylmethyl-sulfanylmethyl)benzene (4tet) are given. The synthesis and characterisation of the Ag(I), Cu(II) and Cd(II) complexes formed with these three ligands are also given. The complex of [Cd(2tet)(NO₃)₄] was structurally characterised by X-ray diffraction and was found to be a discrete species. The complexes {[Ag₂(3tet)](ClO₄)₂}n̲, {[Ag₂(3tet)](PF₆)₂}n̲, {[Ag₂(3tet)](CF₃CO₂)₂}n̲, {[Ag₂(4tet)]-(ClO₄)₂�2MeCN�2CHCl₃}n̲, {[Ag₂(4tet)](PF₆)₂�6MeCN}n̲ and {[Ag₂(4tet)](ClO₄)₂-�3H₂O}n̲ were likewise structurally characterised by X-ray diffraction. All these complexes were three-dimensional coordination polymers. A comparison of the seven structures is given at the end of the chapter.
Chapter three reviews rigid four-armed pyridine-containing ligands and their use in coordination chemistry. The preparation of the rigid four-armed ligand 2,3,4,5-tetrakis(4-pyridyl)thiophene (pyth) is given. The synthesis and characterisation of the Ag(I), Cu(I) and Cd(II) complexes formed with this ligand are also given. The complexes [Ag(pyth)](BF₄)�3MeCN�CH₂Cl₂}n̲, [Ag(pyth)](PF₆)�MeCN�CH₂Cl₂}n̲, [Ag(pyth)]-(CF₃SO₃)�2MeCN�CH₂Cl₂}n̲, [Cu(pyth)](PF₆)�MeCN�CH₂Cl₂}n̲ and [(Cu₂I₂)(pyth)]-(BF₄)�1/2CH₂Cl₂�H₂O}n̲ were structurally characterised by X-ray diffraction. The complex with CuI was a two-dimensional coordination polymer, and the other four complexes were three-dimensional coordination polymers. A comparison of the five structures is given at the end of the chapter.
Chapter four begins with a review of rigid angular bridging ligands and their use in coordination and supramolecular chemistry. The preparation of the ligand bis(4-pyridyl)amine (bpa) is given. The structural arrangement of bpa in the solid state was determined by X-ray diffraction. Complexes of Ag(I), Cu(I), Cu(II) and Cd(II) formed with this ligand were synthesised and characterised. The complexes {[Ag(bpa)(MeCN)](CF₃SO₃)}n̲, {[Ag(bpa)](PF₆)�MeCN}n̲, {[Ag(bpa)](ClO₄)-�2MeCN}n̲, {[Ag(bpa)](ClO₄)}n̲, {[Ag(bpa)](NO₃)}n̲, [(Cu₂I₂)(bpa)₂]n̲, {[Cu(bpa)₂Cl₂]-�3DMF�3/2H₂O}n̲, {[Cd(bpa)₂(NO₃)(H₂O)](NO₃)}n̲, {[Cd(bpa)₂(SO₄)(H₂O)]�3H₂O}n̲, [Cd(bpaH)₂(SO₄)₂(H₂O)₂]�2MeCN and {[Cd(bpa)(SCN)₂]�1/5iPrOH}n̲ were structurally characterised by X-ray diffraction. All complexes with Ag(I) were one-dimensional coordination polymers, with two of them helical, the other three zigzag. Both complexes with Cu(I) and (II) were two-dimensional coordination polymers. One complex with CdSO₄ was discrete, with the bpa ligands mono-protonated, but all other three other Cd(II) complexes were three-dimensional coordination polymers. Seven of these complexes showed hydrogen-bonding interactions linking them together to form supramolecular structures of higher dimensionalities. A comparison of the twelve structures is given at the end of the chapter.
Chapter five is a brief summary of the outcomes of this thesis.
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Sampanthar, J. T. "Multinuclear NMR studies on rhodium compounds containing N-heterocyclic ligands." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295834.
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Chen, Xiaoping. "Synthesis, structure and catalytic property of transition metal complexes with phosphorus-nitrogen and sulfur-nitrogen ligands." HKBU Institutional Repository, 2002. http://repository.hkbu.edu.hk/etd_ra/361.
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Tse, Man Chung. "Preparation and reactivity of transition-metal complexes of polydentate ligands containing both amino and phosphino functional groups." HKBU Institutional Repository, 1995. http://repository.hkbu.edu.hk/etd_ra/46.
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Williams, Charlotte Katherine. "Novel ferrocenediyl ligands, their transition metal complexes and potential for catalysis." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246677.
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Scharf, Austin Bennett. "First-Row Transition Metal Complexes of Dipyrrinato Ligands: Synthesis and Characterization." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11090.
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A library of variously-substituted dipyrrins and their first-row transition metal (Mn, Fe, Cu, Zn) complexes have been synthesized, and the effects of peripheral substituents on the spectroscopic, electrochemical, and structural properties of both the free-base dipyrrins and their metal complexes has been explored. The optical and electrochemical properties of the free dipyrrins follow systematic trends; with the introduction of electron-withdrawing substituents in the 2-, 3-, 5-, 7-, and 8-positions of the dipyrrin, bathochromic shifts in the absorption spectra are observed, oxidation becomes more difficult, and reduction becomes more facile. Similar effects are seen for iron(II) dipyrrinato complexes, where peripheral substitution of the dipyrrinato ligand induces red-shifts in the absorption spectra and increases the oxidation potential of the bound iron. Steric interactions between the peripheral halogens and the 5-substituent of the dipyrrinato ligand can induce distortion of the ligand from planarity, resulting in widely varying 57Fe Mössbauer quadrupole splitting (|ΔEQ|) parameters.Chemistry and Chemical Biology
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Bhachu, Tarnjeet Singh. "Synthesis and characterisation of transition metal complexes of functional dithiolene ligands." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436866.
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Atkinson, Nigel Anthony. "Transition metal complexes with sulphur/nitrogen donor macrocycles and related ligands." Thesis, University of Huddersfield, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.290395.
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Koe, Julian Robert. "The fluxional behaviour of transition metal complexes of chalcogen-alkene ligands." Thesis, University of Exeter, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328487.
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Halcovitch, Nathan Ross. "Phosphinoamide ligands for the synthesis of early transition metal organometallic complexes." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45102.
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Early transition metal hydrides are currently of great interest; they are intermediates in catalytic processes, and have demonstrated ability to activate small molecules. While these complexes are traditionally supported by cyclopentadienyl-type ancillary ligands, current efforts are focused on alternative architectures. In particular, chelating mixed-donor ancillary ligands are currently employed for the synthesis of metal hydride complexes. Bidentate phosphinoamide ligands ([ArNPiPr₂]¹- where Ar = 3,5-dimethylphenyl) were used herein for the synthesis of scandium, yttrium and zirconium organometallic complexes that were characterized using NMR spectroscopy and X-ray diffraction techniques.
Mixed phosphinoamide-alkyl yttrium complexes were generated in solution as a mixture of products from reaction of ArNHPiPr₂ with Y(CH₂SiMe₃)₃(THF)₂. Using the same methodology, (ArNPiPr₂)₂Sc(CH₂SiMe₃)(THF) was prepared and reaction with H₂ or PhSiH₃ gave the ligand redistribution product (ArNPiPr₂)₃Sc(THF), along with insoluble materials. A ferrocene-linked diphosphinoamide ligand was developed ([fc(NPiPr₂)₂]²- where fc = 1,1′-ferrocenyl) and employed for the synthesis of a discandium dihydride complex which is bridged by both hydride and phosphinoamide ligands. Because of the insolubility of this discandium dihydride subsequent attempted reactions with CO, alkenes and alkynes were unsuccessful.
Triphosphinoamide zirconium complexes (ArNPiPr₂)₃ZrX (X = Cl, Et, CH₂Ph, BH₄, PHPh) were prepared and proved to be poor precursors for the synthesis of a zirconium hydride complex. The ferrocene-linked diphosphinoamide ligand was used in the synthesis of zirconium organometallic complexes, fc(NPiPr₂)2ZrR₂ (R = Me, CH₂Ph, CH₂tBu, tBu). While these dialkyl zirconium complexes were unreactive with respect to H₂, they have been shown to undergo insertion of (2,6-dimethylphenyl)isocyanide to generate the expected iminoacyl complexes. The reactivity of the iminoacyl complexes has been examined and a thermally induced 1,2-hydrogen shift reaction was observed for the benzyl-substituted iminoacyl, to generate an amidoalkene complex; the kinetics of the transformation were studied and deuterium isotopic labelling experiments revealed a primary isotope effect for the migrating hydrogen.
The electrochemical oxidation of ferrocene-linked diphosphinoamide scandium and zirconium complexes was examined using cyclic-voltammetry; irreversible oxidation of the ferrocenyl diphosphinoamide ligand in these complexes was observed.
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Rösel, Pirmin. "Mononuclear and oligonuclear transition metal complexes with acyclic and macrocyclic ligands /." [S.l.] : [s.n.], 2009. http://edoc.unibas.ch/diss/DissB_8780.
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Monticelli, Marco. "Novel di(N-heterocyclic carbene) ligands and related transition metal complexes." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAE051.
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Le travail de thèse, en co-tutelle entre l'Université de Padoue et l'Université de Strasbourg, se concentre sur la chimie des carbènes bis-(N-hétérocycliques) et peut être divisé en quatre familles de ligands qui constituent les quatre chapitres du manuscript : i) complexes métalliques de Cu(I), Ag(I), Au(I), Ir(III) et Ru(II) avec des ligands di(carbène N-hétérocyclique) portant un pont phénylène rigide entre les unités carbèniques; ii) complexes métalliques de Cu(I), Ag(I), Au(I) et Ru(II) combinant un ligand NHC fonctionnalisé avec un triazole dans la position 5 du squelette; iii) complexes métalliques d’Ag(I), Au(I) et Pd(II) avec des ligands hétéroditopiques à base d'un imidazol-2-ylidène et d’un 1,2,3-triazol-5-ylidène reliés par un pont propylène; iv) proligands bis (benzoxazoles) et les tentatives de complexation sur des métaux de transitionThe PhD, a collaboration between the University of Padova and the University of Strasbourg, is focused on the chemistry of di(N-heterocyclic carbene) ligands and can be divided in four families of ligands that constitute the four chapters: i) metal complexes (Cu(I), Ag(I), Au(I), Ir(III), Ru(II)) with di(N-heterocyclic carbene) ligands bearing a rigid phenylene bridge between the carbene units; ii) metal complexes (Cu(I), Ag(I), Au(I), Ru(II)) combining an imidazole-based NHC ligand functionalized with a triazole in the 5 position of the backbone; iii) metal complexes (Ag(I), Au(I), Pd(II)) with heteroditopic ligands based on imidazol-2-ylidene and 1,2,3-triazol-5-ylidene moieties connected with a propylene bridge; iv) bis(benzoxazolium) proligands and attempted synthesis of related transition metal complex
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Kawai, Masahiro. "Synthesis and Application of Transition Metal Complexes Bearing Overcrowded Phosphine Ligands." 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/124436.
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Nyamwihura, Rogers. "Synthesis of Gold Complexes From Diphosphine Ligands and Screening Reactions of Heterocyclic Acetylacetonato (ACAC) Ligands with Transitional Metal Complexes." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804890/.
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Syntheses of diphosphine gold (I) complexes from gold THT and two ligands, 4, 5-bis (diphenylphosphino)-4-cyclopenten-1, 3-dione (BPCD) and 2,3-bis(diphenylphosphino)-N-phenylmaleimide (BPPM), were done separately. The reactions happened under ice conditions followed by room temperature conditions and produced two diphosphine gold (I) complexes in moderated yield. Spectroscopic results including nuclear magnetic resonance (NMR) and X-ray crystallography were used to study and determine the structures of the products formed. Moreover, X-rays of all newly synthesized diphosphine gold (I) complexes were compared with the known X-ray structures of other phosphine and diphosphine gold (I) complexes. There were direct resemblances in terms of bond length and angle between these new diphosphine gold (I) complex structures and those already published. For instance, the bond lengths and angles from the newly prepared diphosphine gold (I) complexes were similar to those already published. Where there were some deviations in bond angles and length between the newly synthesized structures and those already published, appropriate explanation was given to explain the deviation. Heterocyclic ligands bearing acetylacetonate (ACAC) side arm(s) were prepared from ethyl malonyl chloride and the heterocyclic compounds 8-hydroxylquinoline, Syn-2-peridoxyaldoxime, quinoxalinol and 2, 6-dipyridinylmethanol. The products (heterocyclic ACAC ligands) from these reactions were screened with transition metal carbonyl compounds in thermolytic reactions. The complexes formed were studied and investigated using NMR and X-ray crystallography. Furthermore, the X-ray structures of the heterocyclic ACAC ligand or ligand A and that of rhenium complex 1 were compared with similar published X-ray structures. The comparison showed there were some similarities in terms of bond length and bond angles.
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King, Adam Charles. "Rhodium complexes of some functionalised pyridine ligands incorporating nitrogen and sulphur donor sets." Thesis, University of Cambridge, 1991. https://www.repository.cam.ac.uk/handle/1810/271927.
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Lutterman, Daniel Aaron. "Investigation of transition metal complexes with potential photochemical applications." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1184601514.
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Zhang, Shuanming. "Synthesis and reactivity of polyfunctional phosphorus ligands and their transition metal complexes." Strasbourg, 2011. http://www.theses.fr/2011STRA6024.
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Les synthèses de ligands chélatés P,N ainsi que celles de leurs complexes de métaux de transition ont suscité un intéret croissant durant ces dernières années, du fait de leurs propriétés struturales intrinsèques et du large champs d’applications. De tels ligands hétérofonctionnels associants un donneur dur, l’azote, et un donneur mou, le phosphore, peuvent conduire à une grande diversité de propriétés chimiques et structurales, et peuvent également générer des systèmes hémilabiles plus réactifs. Nous nous sommes particulièrement intéressé aux systèmes phosphines-thiazoline et phosphines-oxazoline, qui sont souvent actifs en catalyse d’oligomérisation d’olefine. Nous nous sommes également intéressé aux complexes du Pt(II) à ligands fonctionnels tel que PPh2CH2PPh2 (dppm), qui montrent d’intéressantes propriétés de luminescenceThe synthesis of P,N chelating ligands and their transition metals complexes has become increasingly attractive in the last few years owing to their intrinsic structural properties and broad applications. Such heterofunctional ligands possess a hard nitrogen donor with a soft phosphorus donor leading to considerable chemical and structural diversity and may generate hemilabile systems endowed with enhanced reactivity. 1k, 1m We are particularly interested in thiazoline- and oxazoline-based phosphine systems, which are often active in catalytic ethylene oligomerisation. We are also interested in Pt(II) complexes derived from P,P functional ligands derived from Ph2PCH2PPh2 (dppm), which exhibit interesting luminescence properties
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Habtu, Michael M. "A study of the transport, extraction and co-ordination chemistry of a number of thiourea ligands with a series of transition and post-transition metal ions." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/97374.
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Thesis (MSc)--Stellenbosch University, 2003.ENGLISH ABSTRACT: In this study, a number of mono- and di-substituted acyl(aroyl)thioureas were investigated for potential application as specific carriers (ionophores) for the transport and extraction of Ag(l) from a mixture of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(lI) ions. The experimental arrangement for the transport experiments employed a liquid membrane set up involving a 3-phase system - 2 aqueous phases (source and receiving phase) separated by a chloroform membrane incorporating the ligand. Competitive metal ion transport experiments were conducted using the liquid membrane set up. The aqueous source and receiving phases were analyzed using Atomic Absorption Spectroscopy (AAS) and results were confirmed by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICPOES). The transport results show that the N,N-dialkyl-substituted-N'-acyl(aroyl) (HL) thioureas studied, with the exception of the N,N-di-(2-hydroxyethyl)-N'-benzoylthiourea (HL3 ) and N-piperidyl-N'-4-nitrobenzoylthiourea (HL9 ), were efficient and selective for Ag(I). HL9 was also selective for Ag(l) but not efficient. HL3 was selective for Cu(II). Under the experimental conditions employed, 13% Cu(lI) was transported by HL3 . Among the N,Ndialkyl- N'-aroylthioureas, maximum Ag(l) transport was obtained by using N,N-diethyl-N'-4- chlorobenzoylthiourea (HL5 ) and N,N-di-n-butyl-N'-benzoylthiourea (HL \ Under the experimental conditions employed, the percentages of Ag(l) transported by HL5 and HL 1 were 48% and 42% respectively. The transport selectivity and efficiency of 3,3,3' ,3'-tetraethyl-1 ,1'-isophthaloylbisthiourea (H2L12 ) and N,N-diethyl-N'-camphanoylthiourea (HL13)for Ag(l) were also studied. We were particularly interested, in comparing the Ag(l) transport and extraction efficiency of these ligands with that of the HL and H2L ligands. The experimental results reveal that, of all the ligands we investigated in this study, HL 13 was the most efficient and selective carrier for Ag(l) transport. The interesting result is that, depending on the ligand concentration used, HL 13 transported 71-81% of Ag(I). Competitive two-phase metal ion solvent extraction experiments were also performed under conditions similar to the transport studies. The results show that by varying the ligand concentration in the membrane phase, up to 100% Ag(l) can be selectively and efficiently extracted from the mixture of the seven metal ions. Finally, the N,N-di-(n)-butyl-N'-benzoylthiourea (HL1) ligand and its complex with Ag(l) were synthesized. Single crystals of the complex were grown for X-ray crystallography and the crystal and molecular structure of the complex was determined. The crystal structure showed that Ag(l) is bonded to the deprotonated ligand through the S,O atoms forming interesting cluster [Ag (L - S, 0)] 4 in the solid state. This structure is monoclinic and crystallizes in the space group P21!c with a = 17.805 (4) A, b = 21.759 (4) A, c = 36.438 (7) A, f3= 96.34(3)°, Z = 8 and a final R-factor of 5.4%.
AFRIKAANSE OPSOMMING: In hierdie proefskrif is 'n aantal mono- en di-gesubstitueerde asiel(ariel) tioureums ondersoek vir moontlike gebruik as ionofore (spesifieke draers) vir die transportasie en ekstraksie van Ag(l) vanuit 'n mengsel van Co(ll), Ni(II), Cu(II), Zn(II), Cd(II), Ag(l) en Pb(lI) ione. 'n Drie-fase selsisteem is gebruik vir die transportasie eksperimente, twee waterige fases (bron- en ontvang-fase) wat geskei is met die chloroform membraan fase wat die ligande bevat. Kompeterende metaalioon transportasie eksperimente is uitgevoer met behulp van hierdie vloeistof membraan stelsel. Die twee waterige fases is deur middel van Atoomabsorpsie Spektroskopie (AAS) ge-analiseer en resultate is bevestig met gebruik van Induktief-gekoppelde Plasma-Optiese Emissie Spektroskopie (IGP-OES). Die resultate het getoon dat elkeen van die N,N-dialkiel-gesubstitueerde-N'-asiel(ariel) (HL) tioureums, met uitsondering van N,N-di(2-hidroksie-etiel)-N'-benzieltioureum(HL 3) en Npiperidiel- N'-4-nitrobenzieltioureum(HL9 ), doeltreffend en selektief was vir Ag(l) transportasie. HL9 was selektief vir Ag(I), maar die transportasie waarde was nie hoog nie, dws. dit was nie doeltreffend nie. HL3 was selektief vir Cu(II). Met gebruik van ons eksperimentele kondisies is 13% Cu(lI) getransporteer deur HL 3. Van die N,N-dialkiel-N'- ariel tioureums, is maksimum transportasie van Ag(l) verkry met gebruik van N,N-dietiel- N'-4-chlorobenzieltioureum (HL5) en N,N-di-n-butiel-N'-benzieltioureum (HL1). Met gebruik van ons eksperimentele kondisies was die persentasie transportasie van Ag(l) deur HL5 en HL 1 48% en 42% onderskeidelik. Die selektiwiteit en doeltreffendheid van 3,3,3' ,3'-tetra-etiel-1 ,t-isoftaltelblstioureumtl+L 12) en N,N-di-etiel-N'-kamfonieltioureum (HL13) vir Ag(l) transportasie is ook onderneem. Ons was besonder ge-interesseerd om die Ag(l) transportasie en ekstraksie van hierdie ligande te vergelyk met dié van die HL en H2L tipe ligande. Die eksperimentele resultate het getoon dat van al die ligande wat bestudeer is, HL 13 die doeltreffendste en mees selektiewe ionofoor was. Van besondere, belang was dat, afhangend van die ligand konsentrasie wat gebruik is, HL13 71-81% Ag(l) getransporteer het. Kompeterende twee-fase metaalioon vloeistof-vloeistof ekstraksie eksperimente is ook uitgevoer onder toestande soortgelyk aan dié van die transportasie eksperimente. Die resultate toon dat met varierende ligand konsentrasie, tot soveel as 100% Ag(l) selektief en doeltreffend geëkstrakeer word vanuit 'n mengsel van die sewe metaal ione. N,N-di-n-butiel-N'-benzieltioureum (HL1 ) ligande en die kompleks daarvan met Ag(l) is ook gesintetiseer. Enkel-kristalle van die kompleks is verkry en X-straal kristallografiese analiese is onderneem. Die kristalstruktuur toon hoedat Ag(l) gebind is aan die gedeprotoneerde ligand deur die S en Q atome en toon ook interessante [Ag(L-S,Q)]4 groepe in die vaste toestand. Hierdie struktuur is monoklinies en kristaliseer in die ruimtegroep P21!c met a = 17.805(4) Á, b = 21.759(4)Á, c = 36.438(7)Á, P = 96.34(3t, z = 8 en 'n finale R-faktor van 5.4%.