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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Magnetostructural correlations in polynuclear complexes of phtalazine based tetra- and hexadentate ligands /

Sheppard, Christopher Lorenzo, January 1998 (has links)
Thesis (M. Sc.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 147-155.
62

Rate of elimination of water molecules from the first coordination sphere of paramagnetic cations as determined by nuclear magnetic resonance measurements of Oℓß

Stover, Eleanor Diane. January 1960 (has links)
Thesis (M.S. in Chemistry)--University of California, Berkeley, Sept. 1960. / "UCRL-9265." TID-4500 (15th ed.). Bibliography: leaf 33.
63

Hydrothermal synthesis of metal coordination polymers using mixed pyridine-carboxylate ligands /

Lin, Zhuojia. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.
64

Competitive transport, extraction and coordination chemistry of a number of ligands with selected transition and post-transition metal ions /

Sheng, Xia. January 2008 (has links)
Thesis (MSc)--University of Stellenbosch, 2008. / Bibliography. Also avialable via the Internet.
65

Main group supramolecular coordination chemistry : design strategies and dynamic assemblies /

Pitt, Melanie A., January 2009 (has links)
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 160-172) Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.
66

Síntese, caracterização e investigação das atividades biológicas de complexos de cobre(II) contendo moléculas bioativas e ligantes nitrogenados

Silva, Patricia Bento da [UNESP] 21 September 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-21Bitstream added on 2014-06-13T20:38:24Z : No. of bitstreams: 1 silva_pb_dr_araiq_parcial.pdf: 270201 bytes, checksum: 585f52f1db0eaf23bbed52ec96e38cc7 (MD5) Bitstreams deleted on 2015-06-25T13:01:12Z: silva_pb_dr_araiq_parcial.pdf,. Added 1 bitstream(s) on 2015-06-25T13:03:28Z : No. of bitstreams: 1 000712513_20160921.pdf: 237556 bytes, checksum: ed160724489b8fe3d24f76bb41a4fa85 (MD5) Bitstreams deleted on 2016-09-23T13:56:38Z: 000712513_20160921.pdf,. Added 1 bitstream(s) on 2016-09-23T13:57:52Z : No. of bitstreams: 1 000712513.pdf: 10287291 bytes, checksum: 9a55b72e349e9fa39a285e594f6348e4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cobre é o terceiro elemento de transição mais abundante no corpo humano e está presente no sítio ativo de enzimas que participam de reações oxidativas como a citocromo oxidase ou a superóxido dismutase. Além disso, é reconhecido há muito tempo que compostos de cobre são capazes de inibir uma gama de fungos e bactérias. Dentro dessa perspectiva, o objetivo principal deste trabalho consistiu na síntese, caracterização e investigação da atividade antibacteriana de complexos de cobre(II) contendo como ligantes moléculas bioativas {etambutol (EMB), isoniazida (INH) e pirazinamida (PZA)}, ácido isonicotínico (Hina), diaminas {N-dodecil-1,2-etanodiamina (L1), N-tetradecil-1,2-etanodiamina (L2), N,N´-bisdodecil-1,2-etanodiamina (L3), N-dodecil-1,3-propanodiamina (L4), N-tetradecil-1,3- propanodiamina (L5)} e aminoálcoois {N-tetradecil-2-amino-etanol (L6), N-tetradecil-2-amino-propanol (L7), 2-(tetradecilamino)-2´-metil-1-propanol (L8) e N-tetradecildietanolamino (L9)}. Foram preparados 14 compostos de cobre(II) inéditos: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) e [CuCl2L9] (20). Os compostos foram caracterizados por análise elementar, espectroscopia vibracional no infravermelho, espectroscopia eletrônica no UV/Visível, ressonância paramagnética eletrônica e por análsie térmica (TGA e DTA). O composto [CuCl2(L4)2] H2O (15) teve sua estrutura determinada por difratometria de raios X de monocristal. A superfície dos compostos foi analisada por microscopia eletrônica de varredura e a textura porosa dos compostos [Cu(NCS)2(INH)2]·5H2O (4) e... / Copper is the third most abundant transition metal element in biological systems and was recognized as essential biological element in 1920. The use of copper salts as fungicide has been known for a long time. The main purpose of this study consisted in the synthesis, spectroscopic characterization and investigation of the antibacterial activity of copper(II) complexes containing biological active molecules {ethambutol (EMB), isoniazid (INH) and pyrazinamide (PZA)}, isonicotinic acid (Hina), diamines {Ndodecyl- 1,2-ethanediamine (L1), N-tetradecyl-1,2-ethanediamine (L2), N,N´-bisdodecyl-1,2- ethanediamine (L3), N-dodecyl-1,3-propanodiamine (L4), N-tetradecyl-1,3-propanodiamine (L5)} and amino alcohols {N-tetradecyl-2-amino-ethanol (L6), N-tetradecyl-2-amino-propanol (L7), 2- tetradecylamino)-2´-methyl-1-propanol (L8) and N-tetradecyldiethanolamine (L9)}. Fourteen new complexes were prepared: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) and [CuCl2L9] (20). The compounds were characterized by elemental analysis, infrared spectroscopy, UV-Vis spectroscopy, electron paramagnetic resonance, thermogravimetry and differential thermal analysis. The compound [CuCl2(L4)2]·H2O (15) had its structure determined by single crystal X ray diffraction. The surface of the compounds was analysed by scanning electron microscopy, and the porous texture of the complexes [Cu(NCS)2(INH)2]·5H2O (4) and [Cu(NCO)2(INH)2]·4H2O (5) was analysed by nitrogen adsorption-desorption (ASAP technique), which showed that both complexes are mesopores. The copper(II) complexes were submitte... (Complete abstract click electronic access below)
67

Síntese, caracterização e investigação das atividades biológicas de complexos de cobre(II) contendo moléculas bioativas e ligantes nitrogenados /

Silva, Patricia Bento da. January 2012 (has links)
Orientador: Regina Celia Galvão Frem Di Nardo / Banca: Marlus Chorilli / Banca: Victor Marcelo Deflon / Banca: Alexandre Cuin / Banca: Gustavo Von Poelhsitz / Resumo: O cobre é o terceiro elemento de transição mais abundante no corpo humano e está presente no sítio ativo de enzimas que participam de reações oxidativas como a citocromo oxidase ou a superóxido dismutase. Além disso, é reconhecido há muito tempo que compostos de cobre são capazes de inibir uma gama de fungos e bactérias. Dentro dessa perspectiva, o objetivo principal deste trabalho consistiu na síntese, caracterização e investigação da atividade antibacteriana de complexos de cobre(II) contendo como ligantes moléculas bioativas {etambutol (EMB), isoniazida (INH) e pirazinamida (PZA)}, ácido isonicotínico (Hina), diaminas {N-dodecil-1,2-etanodiamina (L1), N-tetradecil-1,2-etanodiamina (L2), N,N'-bisdodecil-1,2-etanodiamina (L3), N-dodecil-1,3-propanodiamina (L4), N-tetradecil-1,3- propanodiamina (L5)} e aminoálcoois {N-tetradecil-2-amino-etanol (L6), N-tetradecil-2-amino-propanol (L7), 2-(tetradecilamino)-2'-metil-1-propanol (L8) e N-tetradecildietanolamino (L9)}. Foram preparados 14 compostos de cobre(II) inéditos: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) e [CuCl2L9] (20). Os compostos foram caracterizados por análise elementar, espectroscopia vibracional no infravermelho, espectroscopia eletrônica no UV/Visível, ressonância paramagnética eletrônica e por análsie térmica (TGA e DTA). O composto [CuCl2(L4)2] H2O (15) teve sua estrutura determinada por difratometria de raios X de monocristal. A superfície dos compostos foi analisada por microscopia eletrônica de varredura e a textura porosa dos compostos [Cu(NCS)2(INH)2]·5H2O (4) e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Copper is the third most abundant transition metal element in biological systems and was recognized as essential biological element in 1920. The use of copper salts as fungicide has been known for a long time. The main purpose of this study consisted in the synthesis, spectroscopic characterization and investigation of the antibacterial activity of copper(II) complexes containing biological active molecules {ethambutol (EMB), isoniazid (INH) and pyrazinamide (PZA)}, isonicotinic acid (Hina), diamines {Ndodecyl- 1,2-ethanediamine (L1), N-tetradecyl-1,2-ethanediamine (L2), N,N'-bisdodecyl-1,2- ethanediamine (L3), N-dodecyl-1,3-propanodiamine (L4), N-tetradecyl-1,3-propanodiamine (L5)} and amino alcohols {N-tetradecyl-2-amino-ethanol (L6), N-tetradecyl-2-amino-propanol (L7), 2- tetradecylamino)-2'-methyl-1-propanol (L8) and N-tetradecyldiethanolamine (L9)}. Fourteen new complexes were prepared: [Cu2(NCS)4(EMB)] (2), [Cu(NCS)2(INH)2]·5H2O (4), [Cu(NCO)2(INH)2]·4H2O (5), [CuI2(PZA)2] (8), [CuCl2(Hina)2] (9), [CuCl2(L1)2]·2H2O (12), [CuCl2(L2)2] (13), [CuCl2(L3)2]·2H2O (14), [CuCl2(L4)2]·H2O (15), [CuCl2(L5)2]·H2O (16), [CuCl2L6] (17), [CuCl2L7]·4H2O (18), [Cu(SO4)L8]·4H2O (19) and [CuCl2L9] (20). The compounds were characterized by elemental analysis, infrared spectroscopy, UV-Vis spectroscopy, electron paramagnetic resonance, thermogravimetry and differential thermal analysis. The compound [CuCl2(L4)2]·H2O (15) had its structure determined by single crystal X ray diffraction. The surface of the compounds was analysed by scanning electron microscopy, and the porous texture of the complexes [Cu(NCS)2(INH)2]·5H2O (4) and [Cu(NCO)2(INH)2]·4H2O (5) was analysed by nitrogen adsorption-desorption (ASAP technique), which showed that both complexes are mesopores. The copper(II) complexes were submitte... (Complete abstract click electronic access below) / Mestre
68

Deprotonated aza-crown ligands as simple and effective alternatives to C₅Me₅ in group 3, 4, and lanthanide chemistry

Lee, Lawrence Way Mung 26 June 2017 (has links)
The ability of a deprotonated aza-crown ether to allow isolation of soluble lanthanide and yttrium complexes has been investigated. A convenient route to these complexes has been demonstrated by the protonolysis reactions of Ln[(N(SiMe₃)₂]₃ with 4,13-diaza-18-crown-6. NMR spectroscopy and X-ray crystallography revealed a C₂V structure consisting of a basket shaped geometry. The successful protonolysis route has been extended to the preparation of stable alkyls, dialkyls, and alkyl cations of yttrium and zirconium stabilized by deprotonated aza- crown macrocycles. A yttrium, alkyl complex containing deprotonated diaza-18-crown-6 has been prepared by the protonolysis route. The thermal stability and reactivity of this complex were investigated. This alkyl reacts with terminal alkynes to produce a complex equilibrium between the colourless monomeric and dimeric alkynides and a purple Z-butatrienediyl (ie.RC=C=C=CR²⁻) coupling product. NMR studies demonstrate that electron poor alkynes favour coupling and that the carbon-carbon double bond forming process is readily reversible at room temperature. The flexibility of the deprotonated diaza-crown ligand is apparent from the isolation of both cis and trans-zirconium dibenzyl complexes from the protonolysis of tetrabenzyl zirconium with 4,13-diaza-18-crown-6. The structure of both isomers were investigated by NMR spectroscopy and X-ray crystallography. Both the cis and trans-isomers cleanly converted to the stable cation either by protonolysis with [n-Bu₃NH]⁺[BPh₄]⁻ or by alkyl abstraction with B(C₆F₅)₃. The reactivity of the alkyl cation derived from the reaction with B(C₆F₅)₃ was investigated. The reaction of this cation with t-BuNC gave a vinylamide complex following a 1,2-proton rearrangement of an initially formed iminoacyl. Two members of the still rare yttrium dialkyl class of compounds were isolated using monoanionic, deprotonated aza-crown ethers as supporting ligation. The dialkyl complexes were synthesized by protonolysis of Y(CH₂SiMe₃)₃(THF)₂ with either aza-18-crown-6 or aza-15-crown-5. NMR and X-ray analyses of the yttrium dialkyl supported by aza-18-crown-6 indicates a trans-dialkyl geometry while NMR analysis of the aza-15-crown-5 analog indicates a cis-dialkyl geometry. Reaction of the trans-dialkyl complex with CO afforded a trans-dienolate complex formed by the migration of SiMe₃. Alkyl abstraction from the trans-dialkyl complex using B(C₆F₅)₃ allowed generation of the first yttrium, alkyl cation. / Graduate
69

X-ray diffraction studies of co-ordination compounds

Mais, R. H. B. January 1965 (has links)
No description available.
70

Novel aspects of platinum-amine coordination compounds: their chemistry and anticancer application

Bouwer, Yolanda January 2008 (has links)
The aim in this thesis, was to synthesize novel platinum coordination compounds, in order to develop compounds with improved anticancer action which could lead to an improved understanding of the mechanism by which they operate and at the same time, improve synthetic methods for their products. The initial work included the development of a novel synthetic method for 1R,2R-diaminocyclohexaneoxalato-platinum(II) (oxaliplatin), by using an essentially non-aqueous solvent medium and direct ligand exchange at elevated temperatures. This was done by a study of the kinetics of the reaction in a variety of conditions; such as relative reagent concentrations and ratios as well as solvent mixtures. An effective method was developed which could be applied industrially. An international patent was taken out on this method. Various amine complexes of platinum(II) were synthesized using chloro, bromo and oxalato groups as leaving groups. The non-leaving groups were selected having certain specific characteristics in mind. Novel mononitroplatinum(IV) complexes were synthesized, mostly with oxalato leaving groups. One of these in particular, had excellent anticancer behaviour. Another trichloromononitro complex was also synthesized with very good anticancer properties. Two international patents were filed for the latter two compounds. As far as possible, all compounds were studied by spectrometric, chromatographic and thermal methods. They were also tested against 3 cancer cell lines namely cervical (Hela), Colon (HT29) and Breast (MCF7) cancer cells.

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