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1
Rzycka-Korzec, Roksana. "Projektowanie i synteza pochodnych imidów aromatycznych o potencjalnych zastosowaniach w farmacji lub optoelektronice." Doctoral thesis, Katowice : Uniwersytet Śląski, 2020. http://hdl.handle.net/20.500.12128/16085.
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The purpose of this study was to design and synthesize aromatic imides as potential active fragments of new drugs and materials for organic electronics. The first group of tested compounds was formed by conjugating naphthalic or phthalic fragment with thiosemicarbazone containing unsaturated six-membered rings of piperidine, piperazine and morpholine. The second group was iminaphthalimides obtained by introducing aliphatic or aromatic substituents into the imide part and forming an imine bond located in position 3 of the 1,8-naphthalimide core by the condensation of amines with salicylaldehydes.
As a part of this study, 51 compounds were obtained and tested. Following subgroups of these compounds can be indicated: naphthaltiosemiimides (NITs), naphthaltiosemidiimides (NDITs), pyromellitithiosemidiimides (PMITs), 3-nitronaphthalimides (3-NNI), 3-aminonaphthalimides and iminonaphthalimides (ImNI). Chemical structure of the obtained compounds was determined using the ¹H and ¹³C NMR method, while purity was determined by elemental analysis. The physico-chemical and biological tests were performed for the compounds obtained to allow the structure-activity (property) study. Thiosemicarbazones (NITs, NDITs, PMITs) were tested for their complexing capability vs. various metal ions as well as biological activity against the HCT 116p53+/+; HCT 116p53 -/- colorectal and MCF-7 breast cancer cell lines. The study showed a reduction in the ability to complex Cu2+ and Fe3+ by NITs compared to biologically active TSc analogues. This could be explained by the steric hindrance in the imide part. In addition, no cytotoxic properties of these compounds have been demonstrated for the tumor lines tested. However, for imine derivatives (ImNI) the basis characteristics were performed in relation to the measured properties: thermal (TGA, DSC), electrochemical (CV), optical (UV-Vis and PL) in solution and solid (layers or blends). This specifies a potential for the application of these compounds in organic electronics. Electroluminescence (EL) was tested in OLED diodes, where the compound played a role of a layer or a component with PVK:PBD. The best electroluminescent properties both alone and in a form of a component from PVK: PBD was shown by compound ImNI 3a in a weight content of 2%. In addition, due to the lack of cytotoxicity of ImNI to HCT 116, these compounds were also tested for their potential use as fluorescent dyes in bioimaging. These studies showed that both 3-ANI 1 and ImNI: 1a, 1b can be successfully used for imaging live cells. In turn, studies on sublocation of ImNI 1b showed that the compound stains the mitochondria and endoplasmic reticulum. The conducted research allowed us to determine the usefulness of the novel compounds in pharmacy and organic electronics.
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Battirola, Liliane Cristina. "Estruturas grafitizadas e nanocompósitos a base de Poli(imida)/argila organomodificada: síntese, caracterizações e aplicações." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-09042013-090507/.
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Neste trabalho, materiais nanocompósitos de poli(imida) (PI) derivada de BTDA-pFDA-Mel e argila do tipo montmorilonita, organicamente modificada (O-MMT), foram sintetizados usando a metodologia de two-steps. O componente inorgânico do nanocompósito foi adicionado nas concentrações de 3,3, 5,3 e 8,3% em massa. As membranas sintetizadas foram caracterizadas por Espectroscopia de Absorção na Região do Infravermelho com Transformada de Fourrier (FTIR), Difração de Raio X (DRX), Termogravimetria (TG), Espectroscopia de Fotoelétrons Excitados por Raio X (XPS) e Microscopias Ótica (MO), Eletrônica de Varredura (MEV) e de Transmissão (MET). Os resultados comprovam a formação de PI e uma estrutura de nanocompósito do tipo intercalado, onde a cadeia polimérica expulsa o surfactante do espaço interlamelar; além de apresentar estruturas de argila parcialmente esfoliadas. Os materiais sintetizados foram avaliados como polieletrólito em célula a combustível alcalina (Alkaline Fuel Cell - AFC), obtendo condutividades iônicas em torno de 0,032 S cm-1 e de 0,017 S cm-1 para as membranas de PI pura e de nanocompósito com 3,3% de argila em massa, respectivamente, ambas a 60 °C, as quais são na ordem ou até mesmo superior que os polieletrólitos comercias (Tokuyama®, 0,014 S cm-1) para eletrólito alcalino. Apesar de condutividades razoáveis, a performance obtida para as AFCs em operação não foram satisfatórias, desta forma, membranas de nanocompósitos com PI de cadeia principal de maior mobilidade foram sintetizadas, caracterizadas e avaliadas nas AFCs. Ademais, neste segundo nanocompósito, a adição de grupamentos amino na cadeia principal foram realizados para aumentar a condutividade iônica. Assim, este segundo material apresentou uma maior performance nas AFCs quando comparado com o nanocompósito de PI de cadeia mais rígida e com a membrana comercial Tokuyama® nas mesmas condições. Além disso, a carbonização superficial das amostras foi realizada por meio de tratamento térmico. A formação de estruturas grafitizadas nos materiais de PI pura e dos nanocompósitos foram investigadas por FTIR, DRX, TG, XPS e EPR. Foi encontrado que a formação de estruturas do tipo grafite nas amostras ocorrem principalmente nas primeiras camadas (grafitização superficial), preservando a estrutura interna da poli(imida). Com isso, estruturas poliméricas ou nanocompósitos com superfícies grafitizadas podem atuar tanto como polieletrólitos e ser um caminho promissor para o desenvolvimento de arranjos eletrodo-membrana (Membrane Electrode Assembly - MEA) mais eficientes para células a combustíveis alcalinas, como em processos de catálise heterogênea e processos de separação com membranas.In this work, Poli(imide)/clay (PI/clay) nanocomposite membranes were synthesized by employing a two-steps method using organically modified montmorillonite clay (O-MMT) with different amounts of O-MMT loading (3.3, 5.3 and 8.3 wt.%). Fourier transform infrared spectroscopy (FTIR), X-ray power diffraction (XRD), thermogravimetric analysis (TG), X-ray photoelectron spectroscopy (XPS), optical microscopy (OM), scanning electron microscope (SEM) and transmission electron microscopy (TEM) measurements, confirmed the formation of pure PI and intercalated-nanocomposite structures. The results revealed parallel clay layers with interlamellar PI and some organoclay partially exfoliated. In addition, the polyelectrolyte membranes of PI and PI/O-MMT (3.3 wt.%) showed that the ionic conductivity were 2- and 1-fold, respectively, higher than that of commercial membrane (Tokuyama®, 0.014 S cm-1), in alkaline fuel cells (AFC) at 60 °C. Despite the fact that the membranes of pure PI and PI/O-MMT demonstrated a good degree of ionic conductivity, rapid fuel cell performance deactivation occurred for the temperature higher than 75 °C. Furthermore, the lack of prepared polyelectrolyte ionic groups, led us to consider alternative synthesis of PI/clay nanocomposite membranes. Thus, the performance for second polyelectrolyte was superior when compared to pure PI, PI/O-MMT and commercial Tokuyama® membranes at same conditions. Moreover, the samples were also surface carbonized by thermal treatment. Combining FTIR, XRD, TG, XPS and electron paramagnetic resonance (ESR) analysis, the results suggested that graphitized nanostructures formation occurred mainly on the surface, maintaining the PI bulk structure. Therefore, graphitized PI/clay membranes may act as one promising way for enhancing both membrane electrode assembly in alkaline fuel cells and gas separation or catalysis.
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Angelo, Ulisses Fiorin. "Imidas naftálicas e piromelíticas dissubstituídas como ligantes para complexos de metais de transição \'\'d\'\' com potencial aplicação em redes de coordenação metal-orgânicas." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-10062017-153532/.
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As imidas naftálicas (INs) compõe uma classe de moléculas orgânicas aromáticas derivadas, geralmente, de um anidrido naftálico e uma amina primária. São de grande interesse na área de materiais devido a uma série de propriedades físicas e químicas, mas principalmente devido à suas propriedades fotofísicas. Derivados de INs são compostos fluorescentes com propriedades fotofísicas interessantes como fotoestabilidade, emissão de fluorescência variável (dependendo dos ligantes, pH, temperatura e solvente), solvatocromismo e halocomismo. O estudo de compostos de coordenação formados por imidas naftálicas e metais de transição abre um leque interessante no que tange a pesquisa e desenvolvimento de novos materiais. Esta tese descreve a síntese da imida 4-amino-N-piridina-1,8-naftalimida (NF2), da diimida N,N\'-Bis-(4-piridil)piromelítica (DI1), a determinação dos valores de pKa (2,75 e 3,49), absortividade molar (3537 L.mol-1.cm-1), efeito solvatocrômico (positivo) e rendimento quântico (0,27) de NF2; absortividade molar (18246 L.mol-1.cm-1) e solvatocromismo negativo para DI1. Foram sintetizados compostos de coordenação entre o ligante DI1 e os íons Fe3+; Ru3+ e Co2+, porém a formação de complexos com o ligante NF2 não foi observada por meio das técnicas aplicadasNaphthalic imides (INs) comprise a class of aromatic organic molecules generally derived from a naphthalic anhydride and primary amine. They are of great interest in the field of materials chemistry due to a number of physical and chemical properties, but mainly to their photophysical properties. Derivatives of INs are fluorescent compounds with several interesting photophysical properties such as photostability, variable fluorescence emission (depending on ligands, pH, temperature and solvent), solvatochromism and halochromism. The study of coordination compounds formed between naphthalic imides and transition metals opens up an interesting range of research and development of new materials. This thesis describes the synthesis of 4-amine-N-pyridine-1,8-naphthalimide (NF2) and N, N\'-Bis- (4-pyridyl) pyromellitic diimide (DI1) , measurement of pKa values (2.75 and 3.49), molar absorptivity (3537 L:mol1:cm1), solvatochromic e_ect (positive) and quantum yield (0.27) of NF2; Molar absorptivity (18246 L.mol-1.cm-1) and solvatochromic efect (negative) for DI1. Coordination compounds with DI1 and Fe3+; Ru3+ and Co2+ ions were synthesized; but complexes with NF2 was not observed by the applied techniques
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Souza, Eliseu William de. "Estudo para fabricação de refletores automobilísticos utilizando um material compósito termofixo e um material termoplástico." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-08082011-102352/.
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Na montagem de um farol automobilístico são utilizados diversos materiais, tais como insertos metálicos nas fixações, vidros nas lâmpadas, materiais poliméricos nas lentes, carcaças, molduras, vedações e refletores, além de vernizes, tintas, película de metal para reflexão do feixe luminoso. Há cerca de quatro décadas foi iniciada a confecção dos refletores utilizando o BMC (bulk moulding compound), sigla em inglês para composto para moldagem em forma de massa, que é um compósito polimérico termofixo. Este material apresenta inúmeras vantagens sobre o metal, tal como forma e geometria que podem se integrar facilmente ao desenho do carro, elevada produtividade, baixo custo e da elevada resistência térmica. Contudo, apresentam o inconveniente de não poderem ser reciclados. Uma opção ao BMC tem sido o PEI [poli (éter imida)], que é um material polimérico termoplástico de alto desempenho que apresenta propriedades atrativas para essa utilização. Oferece também elevada produtividade, porém com um custo elevado se comparado ao BMC. Tem a vantagem de pode ser reciclado. De modo a analisar o potencial dos dois materiais e extrair deles suas vantagens competitivas, bem como determinar suas possíveis limitações, o presente trabalho apresenta os resultados de caracterização mecânica, análise térmica, ensaios de impacto, ensaios de temperatura de deflexão térmica (HDT) e reaproveitamento de resíduos de BMC, incorporando-o ao PVC [poli (cloreto de vinila)], resultando uma nova blenda polimérica. O estudo conclui que ambos os materiais podem ser utilizados para fabricação de refletores automobilísticos. No entanto, o preço do PEI é maior que o do BMC, o que desestimula sua utilização em produtos de alta escala de produção, como, por exemplo, o produto do presente trabalho. O BMC por sua vez não pode ser reciclado, exigindo um custo adicional para seu reaproveitamento de maneira a evitar seu descarte em aterro sanitário.For assembly of an automobile headlight a lot of materials are used such as metallic inserts anchors, glass in the lamps, lens of polymeric materials, bezels, frames, fences and reflectors as well as paints, metallic sheet for reflection of the luminous beam. About four decades ago begun the manufacturing of BMC reflectors, which is a thermoset composite material. This material presents countless advantages on the metal, such as shape and geometry that can easily integrate the designing of cars, high productivity, low cost and high heat resistance. However, they have the disadvantage of not being able to be recycled. An option to the BMC has been the PEI [poly (ether imide)], which is a high performance polymeric thermoplastic material which brings attractive properties for the production of reflectors. It also offers high productivity, however with a high cost compared to BMC. It also has the advantage of being recycled. In order to analyze the potential of both materials and extract their competitive advantages, as well as determine their possible limitations, this study presents the results of mechanical characterization, thermal analysis, impact tests, tests on heat deflection temperature (HDT) and the reuse of BMC waste, incorporating it to PVC [poly (vinyl chloride)], resulting in a new polymeric blend. The study concludes that both materials can be used for manufacturing automobile reflectors. However, the price of PEI is higher than the one of BMC, which discourages their use in high-scale production products, as the one of this work. The BMC for your time can not be recycled, demanding an extra cost for their reuse, avoiding its disposal in landfill.
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Barbarini, Fernando de Lucca. "Membranas de peneira molecular de carbono obtidas pela pirólise de poli(imidas) ramificadas." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-26072010-093355/.
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Nesse trabalho obtiveram-se membranas de poli(imida) ramifricada com tamanho de poro ajustável usando melamina como agente de ramificação e indutor da formação de poros. Estas poli(imidas) foram sulfonadas usando-se ácido sulfúrico concentrado eficazmente. Finalmente, obtivemos membranas de carbono molecular por pirólise sob atmosfera inerte das poli(imidas) ramificadas. Estas membranas apresentam canais micrométricos paralelos à superfície e uma estrutura assimétrica constituída de uma camada densa filtrante e uma camada com canais micrométricos paralelos à superfície altamente ordenados. A membrana apresentou boa estabilidade química frente ao ataque por radicais hidroxila gerados via reação de Fenton.In this work was obtained branched poly(imides) with tuned pore size using melamine as branching and pore induction agent. The poly(imides) with were efficiently sulfonated with concentrated sulfuric acid. Finally, the molecular sieve carbon membranes were obtained by pyrolysis under inert atmosphere of the branched poly(imides). These membranes have an asymmetric structure with a dense filtering layer and a porous layer with highly ordered channels standing parallel to the surface. These membranes display good chemical stability toward hydroxyl radical attack produced by Fenton reaction.
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Dunn, Simon Charles. "New titanium imido complexes." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320787.
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Bláhová, Petra. "Imidž značky Kérastase Paris." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-192371.
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The aim of the diploma thesis is to determine a perception of the brand Kérastase Paris by consumers in Czech republic and Slovakia and compare it with the identity of the brand. I want to expose consumer habbits in the field of hair care and find out opinion about marketing communication of the brand Kérastase, that is supposed to correspondent with the brand strategy. I also want to expose main characteristics of loyal customer of the brand and propose some marketing recommendation for the brand Kérastase Paris.
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Walker, Gary Lawrence Patrick. "Studies in imido molybdenum chemistry." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266639.
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Humphries, Martin J. "Studies in niobium imido chemistry." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302068.
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Forster, Glyn Daniel. "Dithiocarbamate stabilised molybdenum imido complexes." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261809.
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Ranade, Ajit. "Polyamide-imide and Montmorillonite Nanocomposites." Thesis, University of North Texas, 2001. https://digital.library.unt.edu/ark:/67531/metadc2873/.
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Solvent suspensions of a high performance polymer, Polyamide-imide (PAI) are widely used in magnetic wire coatings. Here we investigate the effect that the introduction of montmorillonite (MMT) has on PAI. MMT was introduced into an uncured PAI suspension; the sample was then cured by step-wise heat treatment. Polarized optical microscopy was used to choose the best suitable MMT for PAI matrix and to study the distribution of MMT in PAI matrix. Concentration dependent dispersion effect was studied by x-ray diffraction (XRD) and was confirmed by Transmission electron microscopy (TEM). Differential scanning Calorimetry (DSC) and Thermogravimetric analysis (TGA) was used to study impact of MMT on glass transition temperature (Tg) and degradation properties of PAI respectively. Micro-hardness testing of PAI nanocomposites was also performed. A concentration dependent state of dispersion was obtained. The glass transition (Tg), degradation and mechanical properties were found to correlate to the state of dispersion.
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Demarchi, Angelita de Araujo. "Síntese caracterização de materiais híbridos de poliamida-imida (PAI) e copolissilsesquioxanos de 3-aminopropiltrietoxissilano (APES) e feniltrietoxissilano (PTES)." Universidade do Estado de Santa Catarina, 2011. http://tede.udesc.br/handle/handle/1780.
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Polyamide-imide (PAI) is a polymer widely used in magnet wires for electrical applications due to combination of their mechanical, electrical and thermal properties. This polymer can be improved by the addition of inorganic moieties, among them silsesquioxanes, forming organic/inorganic hybrids. This dissertation presents the preparation of hybrid polymers PAI/copolysilsesquioxane (PAI/coPSQ), where the matrix of polyamide-imide (PAI) is prepared from the condensation of trimellitic anhydride (TMA) and diphenylmethane-4 ,4-diisocyanate (MDI), and the copolysilsesquioxane is prepared by the sol-gel method from alkoxide precursors, in this case, 3-aminopropyltriethoxysilane (APES) and phenyltrietoxisilane (PTES). The methods for obtaining the hybrid PAI/coPSQ by simple mixing and in situ reaction were evaluated. The hybrid polymers were characterized by their spectroscopic characteristics, morphology, electrical, mechanical and thermal properties. The PAI/coPSQs coatings prepared with APES-rich coPSQ presented gelatinization due to high crosslinking generated by the polymer chains of PAI and the amine groups of PSQ. The method of in situ reaction mixture was more efficient in the generation of hybrid PAI/coPSQ, minimizing the occurrence of gelatinization. The SEM and AFM confirmed the absence of separation between the organic and inorganic phases and the FTIR and NMR 13C and 29Si analysis confirmed the formation of a Si-O-Si network. PAI/coPSQ hybrid samples showed no significant changes of Tg, while PAI/PTES hybrid obtained by polycondensation of PTES presented a decrease of Tg. PAI/PSQs hybrids were analyzed by thermogravimetry and showed a small improvement in thermal resistance. The results of nanoindentation tests confirmed the influence of adding coPSQ to increase hardness and elastic modulus of PAI films, while the average performance of dielectric strength showed trends of increasement.
O polímero poliamida-imida (PAI) é amplamente utilizado em fios esmaltados para aplicações elétricas devido ao balanço de suas propriedades mecânicas, elétricas e térmicas. Este polímero pode ser melhorado pela adição de cargas inorgânicas em sua matriz, dentre elas os silsesquioxanos, formando híbridos orgânicos/inorgânicos. O presente trabalho apresenta o preparo de polímeros híbridos PAI/copolissilsesquioxano (PAI/coPSQ), onde a matriz de poliamida-imida (PAI) é preparada a partir da reação de condensação entre o anidrido trimelitico (TMA) e o difenilmetano-4,4-diisocianato (MDI), e o copolissilsesquioxano é preparado pelo método sol-gel a partir de precursores alcóxidos, neste caso o 3-aminopropiltrietoxissilano (APES) e o feniltrietoxissilano (PTES). Foram avaliadas as metodologias de obtenção do híbrido PAI/coPSQ por mistura simples e por reação in situ. Os polímeros híbridos foram caracterizados quanto às suas características espectroscópicas e morfológicas, propriedades elétricas, mecânicas e térmicas. Os vernizes de PAI preparados com coPSQs ricos em APES apresentaram gelatinização devido ao alto grau de reticulação gerado pelas ligações cruzadas entre as cadeias poliméricas do PAI e os grupos amínicos. O método de mistura por reação in situ mostrou-se mais eficiente na geração do híbrido PAI/coPSQ, minimizando a ocorrência de gelatinização. As análises morfológicas confirmaram a ausência de separação entre as fases orgânica e inorgânica e as análises de FTIR e NMR 13C e 29Si confirmaram formação da rede Si-O-Si. As amostras híbridas PAI/coPSQ não apresentaram alterações significativas de Tg, enquanto que o híbrido PAI/PTES obtido pela policondensação somente do PTES apresentou grande diminuição de Tg. Os híbridos PAI/PSQs apresentaram uma pequena melhoria na estabilidade térmica analisada por termogravimetria. Os resultados do ensaio de nanoindentação confirmaram a influência da adição do coPSQ para o aumento da dureza e do módulo de elasticidade dos filmes de PAI, enquanto que os resultados médios da propriedade de rigidez dielétrica apresentaram tendência de aumento.
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Pugh, Stephen Merlin. "New imido chemistry with diamide ligands." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312541.
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Norman, Timothy. "Imido and phosphine bridged organometallic complexes." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243522.
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Copsey, May. "Manipulation of group 15 imido architectures." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396641.
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Günyar, Alev Topaloğlu Sözüer Işıl. "Oxo-Imido molybdenum tripyrazolyl borate complexes/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/kimya/T000464.pdf.
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Tombul, Mustafa. "Towards heterometallic group 13 imido complexes." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620961.
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King, Lawrence. "High oxidation state group VI imido metallasiloxanes." Thesis, Queen Mary, University of London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369235.
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Hazari, Nilay. "Titanium imido complexes supported by cyclooctatetraene ligands." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432283.
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Greenhalgh, Daniel Andrew. "Development and applications of cyclic imide desymmetrisations." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289390.
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Collier, Philip Edward. "Synthesis and reactivity of titanium imido complexes." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243752.
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Leedham, Angela Priscilla. "Imido analogues of main group oxo-anions." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247865.
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Kaltenecker-Commercon, Joyce Marie. "Water ingression into poly(imide-siloxane)s /." This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-165710/.
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Kaltenecker-Commerçon, Joyce Marie 1965. "Water ingression into poly(imide-siloxane)s." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/38345.
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The interaction of water vapor with the surface and bulk of poly(imidesiloxane) copolymers has been characterized in an attempt to determine the important factors in the copolymer's resistance to water ingression. The multi-block copolymers were synthesized from benzophenone tetracarboxylic dianhydride, bisaniline P and pre-formed amine-terminated poly(dimethylsiloxane) oligomers, with phthalic anhydride as an end-capping agent. Similar copolymers had been previously shown to have reduced water sorption, increased surface hydrophobicity, and increased adhesive durability in hot/wet environments.
Inverse gas chromatography was used to conduct surface energetics studies on copolymers of different siloxane concentration and a polyirnide homopolymer. Free energies of specific interaction of water vapor, ΔGsp°, with the polymer surfaces were found to decrease with the incorporation of siloxane into the polyirnide. The dispersive components of the solid surface free energy of the siloxane- containing copolymers were equal within error to that of pure poly(dimethylsiloxane), indicating a PDMS-rich, hydrophobic surface. The ΔGsp° of the copolymers were not significantly different, suggesting that the copolymer surfaces were very similar. This indicated a minimum weight percent of siloxane incorporation required to maximize the copolymer's surface water resistance. The minimum amount for the studied system was at most ten percent.
Diffusion coefficients of water vapor in the polyimide and copolymers were determined from gravimetric sorption experiments. Higher levels of siloxane incorporation caused a definite increase in the diffusion coefficient, indicating a decreased resistance to water ingression. The increase in diffusion was found to be influenced by siloxane block length and was interpreted in terms of morphological and free volume theories. The diffusion coefficient of a 10 weight percent PDMS copolymer, however, was found to be the same within error as the polyimide diffusion oefficient.
The incorporation of siloxane into polyimides has been shown to increase water resistance due to the hydrophobicity of the siloxane-rich surface. However, high siloxane contents also increased the rate of water ingression in the bulk of the polymer. Increased water resistance of the surface may be achieved at lower siloxane concentrations without increasing diffusive (or decreasing mechanical) properties to undesirable levels.Ph. D.
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Georgiades, Alexis N. "Synthesis and characterisation of novel high temperature polyimides." Thesis, University of Surrey, 2001. http://epubs.surrey.ac.uk/733/.
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Thiering, Swantje. "Synthese und photochemische Transformation imido-substituierter Saccharid-Derivate." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965193411.
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Nie, Fei. "Synthesis and characterization of poly(ester-imide)s /." Online version of thesis, 1989. http://hdl.handle.net/1850/10685.
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Bolton, Paul D. "Synthesis and reactivity of cationic titanium imido complexes." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427896.
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Konidaris, Peter Christopher. "New cyclopentadienyl imido compounds of molybdenum and tungsten." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306573.
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Boyd, Catherine Louise. "Titanium imido compounds with pendant arm amidinate ligands." Thesis, University of Oxford, 2004. http://ora.ox.ac.uk/objects/uuid:00eed787-be37-4863-961b-7a30e99d74f9.
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This Thesis describes the synthesis and characterisation of titanium imido compounds supported by pendant arm functionalised amidinate ligands. Reactivity studies of cyclopentadienyl amidinate-imido compounds with CO2 are presented. Chapter 1 introduces transition metal imido chemistry, with a particular emphasis on imido complexes of titanium. Chapter 2 describes recent developments in the chemistry of functionalised amidinate ligands. The synthesis and characterisation of new titanium imido compounds with pendant amine functionalised amidinate ligands is described. The preparation of an amidinate ligand with a pendant propyl arm is reported. Reactions of a selection of these complexes with small molecules are presented. Chapter 3 reviews recent developments in the chemistry of cyclopentadienyl amidinate-imido compounds. The preparation of cyclopentadienyl-supported titanium imido compounds bearing pendant arm amidinate ligands is described andthereactionsofthesecompoundswithCC>2arediscussed. Kineticanddensity functional theory studies of these reactions are presented. Chapter 4 describes the synthesis and characterisation of alkyl and aryloxide titanium amidinate-imido compounds. The preparation of cationic derivatives is also described and reactions of these cationic derivatives with small molecules are discussed. Chapter 5 presents full experimental procedures for all of the syntheses and reactivity studies outlined in Chapters 2 to 4. Chapter 6 contains characterising data for all of the new compounds reported. Appendices A - K contain tables of selected crystallographic data for all new crystallographically characterised complexes described in this Thesis. Appendices L - O contain kinetics data relating to work discussed in Chapter 3.
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Scondo, Alexandre Barth Danielle Marsura Alain. "La réaction phosphine imide en milieu CO2 supercritique." S. l. : INPL, 2008. http://www.scd.inpl-nancy.fr/theses/2008_SCONDO_A.pdf.
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Ison, Elon Ayinde. "Orbital interactions in group 6 imido diamido complexes." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0005363.
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Kinauer, Markus. "Transient and Stable Terminal Imido Complexes of Iridium." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://hdl.handle.net/21.11130/00-1735-0000-0003-C14D-D.
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Messinis, Antonios Marinou. "Metal imido-catalyzed ethylene and 1-hexene dimerization." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/9449/.
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This thesis investigates the development of well-defined ethylene and 1-hexene dimerization pro-initiators related to the industrially important SASOL α-olefin dimerization system, which consists of WCl6/RNH2/Et3N activated by EtAlCl2. The role of Et3N in the SASOL system is to remove HCl generated from the reaction of the amine with WCl6, something that is suggestive of the possible in situ formation of tungsten imido complexes. To probe the potential role of tungsten imido species, here a range of ethylene and 1-hexene dimerization experiments are described using discrete tungsten, niobium, and tantalum imido complexes in combination with an alkyl aluminum activator (usually EtAlCl2). In order to better understand the possible dimerization mechanisms, selected reactions of the aforementioned imido complexes with alkyl aluminum reagents are also explored. Chapter 1: the industrial importance of olefins and the olefin oligomerization processes are introduced with emphasis on the SASOL α-olefin dimerization system. Mechanistic aspects of the olefin oligomerization process are outlined giving examples of previously reported ethylene and 1-hexene dimerization systems. The aims of this PhD thesis are summarized. Chapter 2: the synthesis and structural characterization of a range of tungsten bis(imido) complexes W(NR)(NR’)Cl2(DME) (R, R’ = alkyl or aryl) is presented. The activity of such complexes as pro-initiators in the dimerization of ethylene and 1-hexene is detailed and the effects of ethylene pressure, temperature, activator, pro-initiator concentration, pro-initiator:activator ratios, and use of additives explored; pro-initiator structure-catalytic activity correlations are established. Preliminary mechanistic studies of tungsten bis(imido)-mediated dimerization are described. Chapter 3: tungsten mono(imido) complexes, W(NR)Cl4(THF) and [W(NR)Cl4]2 (R = alkyl or aryl), are tested in the dimerization of ethylene and 1-hexene. Studies similar to those in Chapter 2 are described, demonstrating that such mono(imido) complexes are reasonably active and selective ethylene and 1-hexene dimerization pro-initiators. Reactions between the tungsten mono(imido) complexes and alkyl aluminum reagents are detailed, providing insight into the role of the aluminum activator in the dimerization process; these suggest that reduction of the tungsten centre is an important part of the initiation process. Hence, discrete W(IV) and W(V) mono(imido) complexes were tested for olefin dimerization, with the latter being active. The beneficial effect of additives (chloride anions, amines) in catalytic dimerization reaction is demonstrated and their mode of action probed. Chapter 4: the use of niobium and tantalum imido complexes, M(NR)Cl3(DME), as pro-initiators is explored. In contrast to their tungsten counterparts these group V imido complexes were able to both polymerize and/or dimerize ethylene, but were inactive towards1-hexene. Chapter 5: full experimental details are presented. Chapter 6: supplementary information including - reactivity of the alkyl aluminum reagents employed for the activation of the pro-initiators; definitions used in the analysis of catalysis test data (TON, etc); and development and validation of methods for the analysis of olefin dimerization products.
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Stevenson, Laura. "New reactions of titanium imido and hydrazido complexes." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:7abf8708-30ca-455f-b53b-a2e1470c3e66.
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This Thesis reports the synthesis and reactions of titanium-nitrogen multiply bonded compounds. Reactions with both acidic and hydridic element-hydrogen bonds are explored along with unsaturated small molecules in general. Chapter One provides a background on imido and hydrazido complexes, starting with the relevance of the hydrazido ligand to nitrogen fixation. Group 4 alkylidene hydrazide and alkoxyimide complexes are also reviewed. The Chapter focuses in particular on the synthesis, structure, and stoichiometric and catalytic reactions of these complexes with unsaturated substrates. Chapter Two describes the synthesis of new titanium imido complexes and the reactions with molecules containing N-H or O-H bonds, internal alkynes and nitriles. The analogous reactions of the hydrazido compound Ti(N2iPrNMe)(NNPh2)(py) are also investigated. Chapter Three details the reactions of the imido compound Ti(N2iPrNMe)(NXyl)(py) with terminal alkynes. Unusual reaction products are described and a full mechanistic study into their formation along with their synthesis and characterisation is presented. In addition, the relevance of these reactions to the catalytic hydrohydrazination of terminal alkynes and diphenylhydrazine with Ti(N2iPrNMe)(NNPh2)(py) is discussed. Chapter Four describes the reactivity of the hydrazido compound Ti(N2iPrNMe)(NNPh2)(py) with a range of silanes and boranes. These reactions are then explored through an in-depth experimental and computational study. Chapter Five presents full experimental procedures and characterising data for the new complexes reported.
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Scondo, Alexandre. "La réaction phosphine imide en milieu CO2 supercritique." Thesis, Vandoeuvre-les-Nancy, INPL, 2008. http://www.theses.fr/2008INPL077N/document.
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Dans l'objectif de proposer un procédé de substitution du phosgène dans la production des isocyanates et de leurs dérivés, nous avons consacré ce travail à l'étude de la réaction phosphine imide dans le CO2 supercritique. Dans ce cadre, nous avons défini une réaction standard et nous avons étudié l'influence des paramètres opératoires sur la cinétique de cette réaction dans le CO2 grâce à un réacteur haute pression de 100 ml. Les analyses des échantillons obtenus ont été réalisées par chromatographie en phase liquide. Ces observations nous ont permis de développer un modèle cinétique du premier ordre, et les résultats obtenus par ce modèle ont permis une bonne prédiction de ceux observés dans un réacteur haute pression de 1l. Nous avons comparé les cinétiques obtenues dans le CO2 avec celles observées dans la diméthylformamide. Nous avons aussi étudié l'influence du "pseudo-catalyseur" permettant l'obtention des isocyanates, et ce dans la diméthylformamide et dans le CO2. Nous avons finalement pu réaliser la synthèse d'un composé d'intérêt pharmaceutique, qui augmente la biodisponibilité du Busulfan, dans le CO2 en utilisant la réaction phosphine imide et suivre la cinétique de cette réactionIn the aim to propose a substitution process to the use of phosgene for the production of isocyanates and their derivatives, we devoted this work to the study of the phosphine imide reaction in supercritical CO2. In this context, we have chosen a standard reaction and investigated the influence of operational parameters on the kinetic of this reaction in CO2 using a high pressure 100 ml reactor. Analyses of the samples were performed using high performance liquid chromatography. These observations permits to develop a first order kinetic model, and we have compared the results obtained using this model with the observations we realized in a high pressure 1l reactor. We have compared the kinetics obtained in CO2 with those observed in dimethylformamide. We have also studied in dimethylformamide and CO2 the influence of the "catalyst" which permits to obtain isocyanates. We've finally performed the synthesis of a compound of pharmaceutical interest, which increase the bioavailability of Busulfan, in CO2 using phosphine imide reaction and we have followed the kinetic of this reaction
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Shay, Daniel Travis. "Synthesis, structure, and reactivity of terminal cobalt imido complexes." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 134 p, 2007. http://proquest.umi.com/pqdweb?did=1257806121&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Al-Hajaji, Abdullah Mosed Ahmed. "Ring opening metathesis polymerisation of some imido norbornene derivatives." Thesis, Durham University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294661.
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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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Swallow, Daniel. "Synthesis and reactivity of macrocycle-supported titanium imido complexes." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243773.
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Bătinaş, Aurora Alexandra. "The chemistry of half-sandwich vanadium imido-amido complexes." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 2009. http://irs.ub/rug.nl/ppn/318.
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Li, Jian-Jun. "Platinum(II) hydroxo, oxo, amido, imido and hydrazido complexes /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9720553.
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Yang, Yi. "Gold(I) oxo, imido, hydrazido complexes and gold clusters /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9841362.
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Giudice, Aldo Edwin. "Synthesis and reactivity of titanium cyclopentadienyl imido amidinate complexes." Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:a4c06c87-d305-4147-a833-f32631b637b0.
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This Thesis describes the preparation and characterisation of a range of titanium imido complexes supported by a cyclopentadienyl-amidinate ligand set. Reactivity studies of these complexes towards unsaturated organic species are presented. Chapter 1 reviews transition metal complexes containing imido, cyclopentadienyl, and amidinate ligands, with an emphasis on recent work. Chapter 2 describes the synthesis and characterisation of titanium cyclopentadienyl imido amidinate complexes, along with precursor complexes which have not been previously reported. X-ray crystal structures of four imidotitanium species are described. Chapter 3 describes the reactivity of titanium cyclopentadienyl imido amidinate complexes towards carbon dioxide. An unprecedented reaction with two molecules of carbon dioxide is reported for the arylimido complexes. X-ray crystal structures of two of the arylimido dicarboxylate products are described. The kinetics of the insertion of the second molecule of carbon dioxide are investigated and reported. Chapter 4 describes the reactivity of titanium cyclopentadienyl imido amidinate complexes towards isocyanates and carbodiimides. The X-ray crystal structures of two N, O- bound ureate complexes are described. A new series of reactions involving two molecules of p-tolyl isocyanate with arylimido complexes is reported. Reactions of isocyanates with carbamate complexes are also reported. Chapter 5 explores the reactivity of titanium cyclopentadienyl imido amidinate complexes towards sulfur-containing substrates. Comparisons are drawn with the reactivity towards oxygen-bearing homologues. X-ray crystal structures of two bridging sulfido complexes are described. Chapter 6 discusses the reactivity of titanium cyclopentadienyl imido amidinate complexes towards substrates containing only one unsaturated linkage. Reactions with organic carbonyls and terminal alkynes are found to afford equilibria rather than isolable products. Chapter 7 details full experimental procedures for all syntheses and reactions described in the text. Chapter 8 contains characterising data for all new compounds reported. Full tables of crystallographic data for all new crystallographically characterised complexes described herein are presented in Appendices A-H, J-M. Appendix I contains kinetics data relating to work discussed in Chapter 3.
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Shields, Carl Monroe. "The synthesis and characterization of maleimide-endcapped imide oligomers." Case Western Reserve University School of Graduate Studies / OhioLINK, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=case1054829455.
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Wang, Chao. "Synthesis and ethylene polymerisation studies of titanium imido complexes." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491615.
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This Thesis describes the synthesis, characterisation and ethylene polymerisation studies ofbititanium imido complexes supported by a variety ofjac-N3 ligands. Chapter 1 introduces homogeneous Ziegler-Natta catalysis, including the role of titanium imido complexes. Bimetallic complexes are reviewed and their polymerisation behaviour is highlighted. Chapter 2 describes the synthesis of new bititanium imido synthons. The X-ray crystal structures and supramolecular structures of bititanium compounds are described and compared with corresponding monometallic counterparts. Chapter 3 describes the synthesis of new bititanium imido complexes supported by a diimido framework with various jac-N3 ligands. A series of single X-ray crystal structures are described and compared with monometallic analogues. Their ethylene polymerisation behavior is investigated and the resulting polyethylene molecular weights compared with mononuclear homologues. Chapter 4 describes the synthesis of new bimetallic complexes linked by the bimacrocyclic ipr4DTNE ligand and the synthesis of new titanium imido compounds supported by the new macrocycle ipr2Me[9]aneN3. The ethylene polymerisation behavior of these complexes is described. Chapter 5 describes the synthesis of Me4DACH supported mono- and bi-titanium imido complexes. The solid state structures including both trans and cis configurations is presented. The ethylene polymerisation behaviour of these compounds is presented. Chapter 6 presents full experimental procedures for Chapters 2 to 5. Chapter 7 contains characterising data for all of the new compounds reported. Appendices A - L contain tables of selected crystallographic data for all new crystallographically characterised complexes described in this Thesis. M contains ethylene uptake figures relating to work discussed in Chapter 3.
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Soisson, Arnaud. "Développement de polymères hydrophobes résistants à haute température pour l’encapsulation de module de puissance." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV024.
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L’objectif de cette thèse était de concevoir denouveaux matériaux polymères hydrophobes pour la protectionde composants semi-conducteurs, résistants à hautetempérature, aux forts champs électriques et aux atmosphèresagressives. Dans ce contexte, les polyimides d’addition sontapparus comme la famille de polymères la mieux adaptée pourl’application envisagée. La synthèse de l’encapsulant étantréalisée directement dans les boîtiers des modules, elle ne peutdonc pas contenir de solvant organique exogène. Ainsi, nousavons développé de nouvelles voies de synthèse sans solvantde poly(aminobismaléimide)s et de poly(bismaléimide)s.Dans un premier temps, différentes diamines aliphatiques ontété utilisées comme solvant réactif lors de la synthèse depoly(aminobismaléimide)s à une température bien inférieure à latempérature de fusion du bismaléimide utilisé (Tf > 300 °C). Unepremière série de 3 nouveaux poly(aminobismaléimide)sréticulés de 70 à 95 % a ainsi été réalisée. A partir de cespremières synthèses, 10 nouveaux poly(aminobismaléimide)sont été élaborés. Pour 9 d’entre eux, des diamines aromatiquesont été utilisées et, pour le dernier, une diamine siloxane. Cesrésultats démontrent la possibilité de généraliser ce procédé desynthèse.Dans un second temps, des poly(bismaléimide)s ont étésynthétisés, toujours sans solvant. Pour cela, les synthèses dequatre nouveaux bismaléimides liquides à température ambianteont été mises au point. Ces composés ont une structurealiphatique ou siloxane dans laquelle un motif pyroméllitique aété, ou pas, introduit. Leur polymérisation amorcée avecl’amorceur radicalaire ad hoc, conduit à la formation desmatériaux sans l’usage de solvant.Selon le choix des réactifs, des matériaux thermodurcissablesou élastomères sont obtenus. Ces derniers semblent mieuxadaptés à l’application souhaitée car, d’une part, la faibleviscosité des mélanges réactionnels permet leur applicationsans difficulté dans un module de puissance et, d’autre part, leurcaractère hydrophobe est plus marqué. L’un d’eux présente unestabilité thermique à 250 °C particulièrement intéressante et unetempérature de relaxation mécanique quasi hors gamme detempérature de fonctionnement. Ce matériau peut doncvraisemblablement être utilisé comme encapsulantThe aim of this work is to develop new hydrophobicpolymeric materials for the protection of semi-conductorcomponents. These materials must withstand high temperature,strong electric fields and aggressive atmospheres such asmoisture. In this context, addition polyimides emerged as themost suitable polymers for the intended application. Thesynthesis of the encapsulant being made directly in the powermodules, it must be solvent free. Thus, we have developed newsolvent free synthesis routes of poly(aminobismaleimide)s andpoly(bismaleimide)s.First of all, different aliphatic diamines were used as a reactivesolvent in the synthesis of poly(aminobismaleimide)s to atemperature well below the melting point of the usedbismaleimide (m.p. > 300 °C). A first series of 3 newpoly(aminobismaleimide)s, crosslinked from 70 to 95 %, hasthus been made. From these first syntheses, 10 newpoly(aminobismaleimide)s have been developed. For 9 of them,aromatic diamines were used and, for the latter, a siloxanediamine. These results demonstrate that this process can begeneralized.Secondly, poly(bismaleimide)s were synthesized, still withoutany solvent. In order to do so, the syntheses of four newbismaleimides, liquid at room temperature, have beendeveloped. These compounds have an aliphatic or siloxanestructure in which a pyromellitic pattern has been or notintroduced. Their polymerization initiated with the suitable radicalinitiator leads to the formation of materials without the use of anysolvent.Depending on the choice of reagents, thermosetting materials orelastomers are obtained. These latter seem more suitable for thedesired application because, on one hand, the low viscosity ofthe reaction mixtures enables their application in a powermodule without any difficulty and, on the other hand, theirhydrophobic behaviour is stronger. One of them has aparticularly attractive thermal stability at 250 ° C and amechanical relaxation temperature almost out of the workingtemperature range. Therefore, this material may be used asencapsulant
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Stewart, Peter John. "Metal-ligand multiply bonded complexes supported by amidinate ligands." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243747.
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King, Evan. "Metal-Ligand Multiple Bonds in High-Spin Complexes." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10356.
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The chemistry of late first row transition metals supported by dipyrromethane and dipyrromethene ligands bearing sterically bulky substituents was explored. Transition metal complexes (Mn, Fe, Co, Ni, Zn) of the dipyrromethane ligand 1,9-dimesityl-5,5-dimethyldipyrromethane (dpma) were prepared. Structural and magnetic characterization (SQUID, EPR) of the bis-pyridine adducts \((dpma)Mn(py)_2\), \((dpma)Fe(py)_2\), and \((dpma)Co(py)_2\) showed each tetrahedral divalent ion to be high-spin, while square planar \((dpma)Ni^{II}(py)_2\) and tetrahedral \((dpma)Zn(py)_2\) were shown to be diamagnetic. Electrochemical experiments revealed oxidative events at common potentials independent of metal identity or spin state, consistent with ligand-based oxidation. Dipyrromethene ligand scaffolds were synthesized bearing large aryl \((Ar = 2,4,6-Ph_{3}C_{6}H_{2}, Mes = 2,4,6-Me_{3}C_{6}H_{2})\) or alkyl \((^{t}Bu = CMe_3, Ad = 1-adamantyl)\) flanking groups to afford three new disubstituted ligands \((^{R}dpme, 1, 9-R_2-5-mesityldipyrromethene, R = Ar, Mes, ^{t}Bu, Ad)\). While high-spin \((S=2)\), four-coordinate iron complexes of the type \((^{R}dpme)FeCl(solv)\) were obtained when R was Mes, tBu, or Ad, use of the sterically encumbered aryl-substituted ligand gave a three-coordinate high-spin \((S=2)\) complex \((^{Ar}dpme)FeCl\). Intramolecular C−H amination was discovered in the reaction of organic azides with \((^{Mes}dpme)FeCl(thf)\), though no intermediate was observed by UV/Vis, IR, or \(^{1}H\) VT-NMR experiments. Reaction of \((^{Ad}dpme)FeCl(OEt_2)\) with alkyl azides resulted in the catalytic amination of C–H bonds or aziridination of olefins at room temperature. Reaction of \(p-^{t}BuC_{6}H_{4}N_{3}\) with \((^{Ar}dpme)FeCl\) permitted isolation of a high-spin \((S=2)\) iron complex \((^{Ar}dpme)FeCl(N(p-^{t}BuC_6H_4))\), featuring a terminal imidyl radical antiferromagnetically coupled to high-spin \(Fe^{III}\), as determined by \(^{1}H\) NMR, X-ray crystallography, and \(^{57}Fe\) Mössbauer. A three-coordinate CoI complex \((^{Ar}dpme)Co(py)\) was synthesized and characterized by \(^{1}H\) NMR, SQUID magnetometry, and X-ray crystallography. Reaction of \((^{Ar}dpme)Co(py)\) with \(^{t}BuN_3\) afforded an isolable three-coordinate Co imide complex \((^{Ar}dpme)Co(N^{t}Bu)\) that exhibits spin crossover from a singlet to a quintet. Reaction of \((^{Ar}dpme)Co(py)\) with mesityl azide produces a spectroscopically observed intermediate, consistent with an \(S=1\) terminal imide complex, that converted via benzylic C–H activation into the metallacycloindoline \((^{Ar}dome)Co(\kappa^{2}-NHC_{6}H_{2}-2,4-Me_{2}-6-CH_2)\).Chemistry and Chemical Biology
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Rodgers, Paula Marie 1967. "Preparation and properties of the tungsten tris(imido) functional group." Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/278281.
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The first tris(imido) complex of a group 6 transition metal, [Li(THF)₄][W(=NAr)₃Cl] (8) (Ar = 2,6 iPr-C₆H₃) was prepared from W(=NAr)₂Cl₂(THF)₂ (2) and 2 equiv of the corresponding lithium amide, LiNHAr in THF. Complex (8) crystallizes in the monoclinic space group P2(1/n) with a = 13.787 (4) Å, b = 17.348 (5) Å, c = 22.781 (8) Å, and β = 90.43 (3)° with Z = 4. The crystal contains discrete C₃ᵥ [W(=NAr)₃Cl]⁻ anions with imido W-N-C(ipso) angles averaging 170.8 (15)° and imido W-N bonds averaging 1.782 (15) Å. The neutral imido species W(=NAr)₃(PMe₃) (15) was made by adding 10 equiv of PMe₃ to (8). "Coupling" of the imido ligand in (15) with CO₂ and O=C=NR (R = Ph, ᵗBu) gave W[NArC(O)O] (=NAr)₂ PMe₃ (20) and W[NArC(O)NR](=NAr)₂PMe₃ (19) respectively. 2,6 Diisopropylaniline was added to (8) to give the complex W(=NAr)₂(NHAr)₂ (9). The chloride ligand of complex (8) was replaced by Li alkyl reagents to yield alkylated product [Li(THF)₄][W(=NAr)₃R] (R = Me, ᵗBu and Np') (11-13). The cation of (8) was substituted by adding ⁿBu₄NBr to afford [ⁿBu₄N][W(=NAr)₃Br] (10). These and related synthetic and reactivity studies will be described.