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Novos tensoativos derivados da 2-D-glucosamina / New surfactants based on 2-D-glucosamineBazito, Reinaldo Camino 13 December 2001 (has links)
Foram sintetizadas duas novas séries de tensoativos de açúcar derivados da 2-D-glucosamina: os metil 2-acilamido-2-deóxi-6-O-sulfonato-D-glucopiranosídeos de sódio (aniônicos) e os cloretos de metil 2-acilamido-2,6-dideóxi-6-trimetilamônio-D-glucopiranosídeos (catiônicos). Os tensoativos aniônicos foram obtidos pela acilação da 2-D-glucosamina com cloretos de acila (com 8, 12 e 16 carbonos), seguida pela metilação desses derivados com metanol em meio ácido, e posterior sulfatação dos metil glucosídeos com complexo trióxido de enxofre-piridina. Os tensoativos catiônicos foram obtidos pela tosilação dos metil glucosídeos, seguida pela quaternização com trimetilamina e troca do contra-íon tosilato por cloreto com resina de troca-iônica. Esses tensoativos apresentaram c.m.c. similares a de outros tensoativos iônicos de cadeia hidrofóbica de igual comprimento, mas energias livres de transferência do grupo polar para a micela muito mais favoráveis. Esse fato foi atribuído à formação de ligações de hidrogênio entre os grupos polares do tensoativo na micela, e à hidrofobicidade do açúcar. As micelas formadas apresentaram números de agregação maiores que os obtidos para outros tensoativos, provavelmente devido às interações atrativas entre os grupos polares. / Two new sugar-based surfactant series were synthesized from 2-D-glucosamine: sodium methyl 2-acylamido-2-deoxi-6-O-sulfonate-D-glucopyranosides (anionic) and methyl 2-acylamido-2,6-dideoxi-6-trimethylamonium-D-glucopyranoside chlorides (cationic). The anionic surfactants were obtained by the acylation of 2-D-glucosamine with acyl chlorides (with 8, 12 and 16 carbons), followed by the methylation of these derivatives with methanol in acidic media, and the sulfation of the methyl glucosides with sulfur trioxide-pyridine complex. The cationic surfactants were obtained by the tosylation of methyl glucosides followed by the quaternization with trimethylamine and exchange of the tosylate contra-ion with chloride ions on an ion exchange resin. These surfactants showed c.m.c. similar to other ionic surfactants with equal hydrophobic chain lengths, but more favorable free energies of transfer of the polar head to the micelle. This fact is attributed to hydrogen bonding between the head groups of the surfactant in the micelle, and the hydrophobicity of the sugar moiety. The micelles of these surfactants showed aggregation numbers larger than those obtained for other surfactants, problably because of head-group attractive interactions.
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An Investigation of Transition Metal Catalysts for Cyanohydrin Hydration: The Interface of Homogeneous and Heterogeneous CatalysisDowns, Emma 29 September 2014 (has links)
Acrylic monomers are important materials that represent a large portion of the economy. The current industrial synthesis hydrates cyanohydrins with sulfuric acid, a process which results in large amounts of waste and significant energy costs. A transition metal catalyzed, acid free hydration of cyanohydrins would be beneficial from both economic and environmental standpoints. However, this reaction is challenging, as many catalysts are poisoned by the cyanide released when cyanohydrins degrade. Therefore the development of a catalyst that is resistant to cyanide poisoning is the ideal method to circumvent these difficulties.
This dissertation describes several cyanohydrin hydration catalysts, with an emphasis on nanoparticle catalysts. These are at the interface between the homogeneous and heterogeneous catalysts that have been explored previously for this reaction. Chapter I surveys previous studies on nanoparticle catalysts for nitrile hydration and their implications for the hydration of cyanohydrins.
Chapter II reports on the homogeneous platinum catalysts [PtHCl(P(NMe2)3)2] and [PtH2(P(NMe2)3)2], exploring secondary coordination sphere effects to enhance nitrile hydration. Chapter III describes another example of this type of complex, [PtH2(P(OMe)3)2], that forms catalytically active nanoparticles under reaction conditions. Explorations of the reactivity of this catalyst with nitriles and cyanohydrins are also described in this chapter.
Chapter IV investigates a silver nanoparticle catalyst with a water soluble phosphine (1,3,5-triaza-7-phosphaadamantane) ligand for its activity towards the hydration of nitriles and cyanohydrins. The results of the degradation of the nanoparticles in the presence of cyanide are also described. Chapter V reports on the preparation and examination of a solid supported nickel catalyst for cyanohydrin hydration. Finally, Chapter VI describes how these investigations have made progress towards the development of a cyanide resistant nitrile hydration catalyst.
This dissertation includes previously published and unpublished co-authored material. / 2015-09-29
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Inserção dos princípios da Química Verde em uma disciplina experimental sob o enfoque Ciência-Tecnologia-Sociedade / Inserting the principles of green chemistry into a experimental discipline under the science-technology-society approachPereira, Kamila Medeiros, (92) 98151-9535 20 August 2018 (has links)
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Previous issue date: 2018-08-20 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The proposal of this study came from the need to popularize Green Chemistry through the insertion of its principles in experimental activities into an introductory practical topic of the Chemistry course in a Public Higher Education Institution in Manaus- AM. Besides investigating the possible contributions of the experiments adapted to Green Chemistry, applied and approached through the Science-Technology-Society - STS approach to the teaching-learning process of the students. Thus, four experiments were selected in the teaching plan of the General Experimental Chemistry, where they were duly adapted to the principles of Green Chemistry, from the substitution of reagents for less harmful ones, as well as a reduction of the quantities used in the analyses. In order to guarantee that the experiments were adapted to Green Chemistry, a tool of evaluation of the green degree of the experiments was used, the called metrics of the Green Chemistry, in this specific case, the metric of the Green Star. Previous to the execution of the experiments by the students, a contextualization of environmental problems present in the daily life was carried out, related to the characteristics of the experiment. It should be stressed that this study was based on the qualitative approach, and on the action-research method. The analysis of the data obtained through questionnaires, annotations, among others, was interpreted by the technique of content analysis. Therefore, the results obtained and analyzed showed that the use of the theme of Green Chemistry allied to the Science-Technology-Society approach in experimental activities contributed in many aspects, such as the promotion of contextual and dynamic experimental activities, where it favoured the learning of conceptual contents, procedural and attitudinal. And also for the feasibility of developing didactic experiments in the practical disciplines of the chemistry courses of the Higher Education Institutions of the State of Amazonas, based on the principles of Green Chemistry in order to direct and empower future citizens and professionals, to design and work with the chemistry of a more conscious and sustainable way. / A proposta desse estudo surgiu da necessidade de popularização da Química Verde, por meio da inserção dos seus princípios nas atividades de experimentação em uma disciplina prática introdutória do curso de Química de uma Instituição de Ensino Superior pública de Manaus-AM. Além de visar também, investigar as possíveis contribuições dos experimentos adaptados a Química Verde, aplicados e abordados por meio do enfoque Ciência-Tecnologia-Sociedade (CTS), ao processo de ensino-aprendizagem dos estudantes. Assim, foram selecionados quatro experimentos presentes no plano de ensino da disciplina de Química Geral Experimental, onde foram devidamente adaptados aos princípios da Química Verde, a partir da substituição de reagentes por outros menos nocivos, assim como diminuição de suas quantidades empregadas nas análises. De forma a garantir que os experimentos foram adaptados a Química Verde, foi utilizada uma ferramenta de avaliação do grau verde dos experimentos, as denominadas métricas da Química Verde, nesse caso em específico, a métrica da Estrela Verde. Anterior a execução dos experimentos pelos alunos, era realizada uma contextualização de problemáticas ambientais presentes no cotidiano, relacionadas a características do experimento. Ressaltasse que referido estudo foi pautado na abordagem qualitativa, e no método de pesquisa-ação. A análise dos dados obtidos por meio de questionários, anotações, entre outros, foram interpretados pela técnica de análise de conteúdo. Portanto, pelos resultados obtidos e analisados, constatou-se que o uso da temática da Química Verde aliada ao enfoque CTS nas atividades experimentais, contribuiu em muitos aspectos, tais como, pela promoção das atividades experimentais contextualizadas e dinâmicas, onde favoreceu a aprendizagem de conteúdos conceituais, procedimentais e atitudinais. E ainda pela viabilidade de desenvolvimento de experimentos didáticos nas disciplinas práticas dos cursos de química das Instituições de ensino superior do Estado do Amazonas, embasados nos princípios da Química Verde, de forma a direcionar e capacitar os futuros cidadãos e profissionais, a conceber e trabalhar com a química de uma forma mais consciente e sustentável.
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Acyl Phosphates: Biomimetic Reagents for Selective Acylation in WaterDhiman, Raj 21 August 2012 (has links)
Acyl groups in biochemical reactions are activated as acyl adenylates; such intermediates are generated by a reaction with ATP. Acyl adenylates are mixed carboxylic-phosphoric anhydrides which are potentially useful as biomimetic reagents for acylation reactions in water. These species have been reported to be unstable and have been isolated without purification. Since the adenylate portion is necessarily complex because it originates from ATP, we reasoned that using a simple alkyl group in place of adenosine might allow the biomimetic process to proceed without the difficulties reported. Our laboratory has developed routes towards such acyl phosphate alkyl monoesters and we have used them for several applications. Such materials react rapidly and selectively with amines in order to produce amides. While reactions utilizing lanthanide ions allow for the selective monoacylation of diols through bis-dentate chelates of the lanthanide. However, the efficiency of diol acylation is limited due to significant hydrolysis of the phosphate reagent and the requirement of a stoichiometric amount of the lanthanide ion. Therefore, three distinct approaches towards improving the efficiency of lanthanide promoted acylation were investigated: addition of an inert co-solvent in an attempt to reduce hydrolysis, eliminating the stoichiometric requirement of the lanthanide by addition of MgII, and the development of immobilized lanthanides as catalysts for acylation. Finally, aminoacyl phosphates are biomimetically activated amino acids and in principle should function as peptide synthesis reagents. The stability and solubility of the activated materials in water presents an opportunity to perform aqueous peptide coupling; such a process is limited by the fact that common peptide coupling agents are either insoluble or unstable in water. Therefore, we investigated the reactions of aminoacyl phosphates with amino acid esters. We find that peptides form readily in buffered solutions, establishing a basis for a general protocol for aqueous amino acid coupling and could be adapted for applications such as solid phase peptide synthesis.
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Acyl Phosphates: Biomimetic Reagents for Selective Acylation in WaterDhiman, Raj 21 August 2012 (has links)
Acyl groups in biochemical reactions are activated as acyl adenylates; such intermediates are generated by a reaction with ATP. Acyl adenylates are mixed carboxylic-phosphoric anhydrides which are potentially useful as biomimetic reagents for acylation reactions in water. These species have been reported to be unstable and have been isolated without purification. Since the adenylate portion is necessarily complex because it originates from ATP, we reasoned that using a simple alkyl group in place of adenosine might allow the biomimetic process to proceed without the difficulties reported. Our laboratory has developed routes towards such acyl phosphate alkyl monoesters and we have used them for several applications. Such materials react rapidly and selectively with amines in order to produce amides. While reactions utilizing lanthanide ions allow for the selective monoacylation of diols through bis-dentate chelates of the lanthanide. However, the efficiency of diol acylation is limited due to significant hydrolysis of the phosphate reagent and the requirement of a stoichiometric amount of the lanthanide ion. Therefore, three distinct approaches towards improving the efficiency of lanthanide promoted acylation were investigated: addition of an inert co-solvent in an attempt to reduce hydrolysis, eliminating the stoichiometric requirement of the lanthanide by addition of MgII, and the development of immobilized lanthanides as catalysts for acylation. Finally, aminoacyl phosphates are biomimetically activated amino acids and in principle should function as peptide synthesis reagents. The stability and solubility of the activated materials in water presents an opportunity to perform aqueous peptide coupling; such a process is limited by the fact that common peptide coupling agents are either insoluble or unstable in water. Therefore, we investigated the reactions of aminoacyl phosphates with amino acid esters. We find that peptides form readily in buffered solutions, establishing a basis for a general protocol for aqueous amino acid coupling and could be adapted for applications such as solid phase peptide synthesis.
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Synthesis, reactivity, and coordination chemistry relevant to the copolymerization of CO2 and epoxides by first row transition metal schiff base complexesFrantz, Eric Benjamin 15 May 2009 (has links)
Excepting agricultural based products, which themselves require a great deal of
energy to produce, our supply of natural resources such as minerals, metal ore, fresh
water, coal, oil and natural gas are all limited in supply. The depletion of these
substances is imminent and this knowledge weighs heavily on humankind. The
utilization of CO2 for the production of polycarbonates is one attempt at exploiting a
profoundly abundant and renewable resource. The importance of research in this and
similar fields justifies the detailed study of the chemicals and procedures involved with
this chemistry. This current work concentrates on the fundamental study of transition
metal Schiff base complexes that have shown a great deal of promise in their ability to
catalyze the copolymerization of CO2 and epoxide to form aliphatic polycarbonates.
A new chromium(III) Schiff base complex has been synthesized and evaluated
for its ability to catalyze the formation of polymer. The ligand employed bears an N2O2
coordination sphere identical to the widely utilized chromium(III) and cobalt(III) salen
catalysts. This complex was shown to be active towards the copolymerization of CO2 and cyclohexene oxide. Although the activity was less than that seen with
chromium(III) salen complex, the study demonstrates that new ligand systems are
available beyond salen and deserve further attention.
A class of manganese(III) Schiff base complexes was also synthesized and
evaluated as catalysts. Although crystallographic data has shown that these complexes
are structural analogs to chromium(III) salens, the difference in metal center leads to a
nearly complete elimination of catalytic activity. Such a marked difference has been
taken advantage of by using this very low activity to study the ring-opening of epoxide
in the initial step of the copolymerization both mechanistically and kinetically. It has
also been utilized in an evaluation of the coordination chemistry of the polymerization
process. This has led to some valuable conclusions about the nature and role of the
metal center that previously have not been studied. Manganese(III) salen complexes
were also synthesized and evaluated in an effort to compare these important ligands to
other Schiff bases and confirm the findings mentioned above.
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PALLADIUM-CATALYZED AMINE SYNTHESIS: CHEMOSELECTIVITY AND REACTIVITY UNDER AQUEOUS CONDITIONSTardiff, Bennett Joseph 23 April 2012 (has links)
The palladium-mediated cross-coupling of aryl electrophiles and amines
(Buchwald-Hartwig amination) has become a widely used method of constructing
arylamine frameworks. A crucial aspect of the advancement of this chemistry has been
the design of ancillary ligands that are able to promote enhanced reactivity in challenging
amination reactions. Despite significant ligand development within the field, challenges
in this chemistry remain.
Chemoselective aminations, wherein one amine substrate undergoes preferential
arylation in the presence of multiple reactive amines has remained an underexplored area
of Buchwald-Hartwig amination chemistry. This thesis describes the use of
[Pd(cinnamyl)Cl]2 and N-[2-di(1-adamantylphosphino)phenyl]morpholine (Mor-
DalPhos) in an extensive study of chemoselective Buchwald-Hartwig aminations, with 62
examples of structurally diverse di-, tri-, and tetraamines obtained in synthetically useful
yields at reasonable catalyst loadings (1-5 mol % Pd). The coordination chemistry of
[(Mor-DalPhos)Pd] species was also explored, as were complementary chemoselective
aminations with the isomeric p-Mor-DalPhos ligand, leading to divergent product formation in some instances. The same [Pd(cinnamyl)Cl]2/Mor-DalPhos catalyst system
used in the chemoselectivity study was also employed in a series of Buchwald-Hartwig
aminations conducted under aqueous and solvent-free conditions, another underexplored
area of this chemistry. A total of 52 amine products were isolated using these
methodologies, moderate catalyst loadings (3 mol % Pd), and without the use of any additional additives, co-solvents, or rigorous exclusion of air.
The synthesis of low-coordinate palladium complexes featuring both NHC and
dialkylchlorophosphine ligands is also discussed herein. These complexes are prepared via a previously unreported and straightforward methodology involving an unusual net PCl bond reductive elimination, and represent a potential new class of pre-catalysts forpalladium-mediated reactions.
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Desenvolvimento de método analítico para a determinação do herbicida paraquat em urina humana /Santiago, João Victor Biagi. January 2018 (has links)
Orientador: Leonardo Pezza / Banca: Jose Anchieta Gomes Neto / Banca: Aristeu Gomes Tininis / Resumo: A proposta apresentada por este trabalho foi estudar e desenvolver um método analítico para a determinação do herbicida paraquat em urina humana, de modo que este seja rápido, sensível, econômico e com uma menor geração de resíduos em relação aos métodos disponíveis, atualmente empregados para esta finalidade, atendendo assim os princípios e requisitos da Química Verde (Green Chemistry) e da Química Analítica Verde (Green Analytical Chemistry). Outro aspecto também abordado, é o emprego da técnica de análise por imagem digital utilizando software analítico através da geração de imagens digitais por meio das fotografias obtidas dos spot-tests, tornando a metodologia portátil e consequentemente mais acessível. O método desenvolvido consiste na reação de redução do dicátion paraquat (PQ2+) para a formação de um cátion radicalar (PQ*+) de coloração azul, utilizando uma solução de glicose (Glc) em meio alcalino (NaOH) como reagente redutor. As concentrações dos reagentes foram otimizadas para obter a maior resposta analítica possível, com o auxílio de ferramentas quimiométricas. O produto colorido possui máxima absorbância em torno de 600 nm, e, devido a coloração azul intenso desenvolvida na sua redução, tornou-se possível sua detecção e quantificação por análise das imagens digitais dos spot-tests da reação no canal de cor vermelho (canal Red do sistema RGB), utilizando-se o software livre "ImageJ - Image Processing and Analysis in Java". Através da análise da intensidade efetiv... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work was proposed study and develop an analytical method for determination and quantification of paraquat herbicide in human urine samples, so that this is rapid, sensible, economic, and lesser waste generating that the related methods in literature, currently employed for this purpose, following with Green Chemistry (G.C.) and Green Analytical Chemistry (GAC) principles. Another approached aspect is employ of Digital Image Analysis (DIA) technique using analytical software through the generating digital images photographed of the spot-tests, making the methodology portable and consequently most accessible. The method developed is based in reduction reaction between paraquat dicátion (PQ2+) for this formation of the radicalar cation (PQ*+) of blue coloring, using a glucose (Glc) solution in alkaline mean (NaOH) as reducing reagent, the reagent concentrations was being optimized for the highest analytical response possible, with the help of the chemometric tools. The colored product has max absorbance at 600 nm, and, because intense blue coloring developed in the reduction, was possible to the detection and quantification from analysis of the digital images of the spot-tests of reaction in red color channel (Red channel of the model RGB), employing the free software ImageJ - Image Processing and Analysis in Java. Through of the analysis of effective intensity (Ar) of the coloring, measured in the red color channel, was plotted an analytical curve that present linearity in... (Complete abstract click electronic access below) / Mestre
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Asymmetric hydroformylation : a powerful tool for the synthesis of pharmaceutical intermediatesNoonan, Gary M. January 2011 (has links)
The hydroformylation of unfunctionalised olefins (such as prop-1-ene and oct-1-ene) is an extremely valuable process and is practised on a massive scale industrially in the synthesis of commodity chemicals. In fact, it represents the worlds largest scale application of homogeneous catalysis. As a result, the majority of research carried out on this reaction has been in the study of catalytic systems which provide high rates and selectivity for the production of linear aldehydes from terminal unfunctionalised olefins, with the products finding use in the production of plasticizers and detergents. Asymmetric hydroformylation, the enantioselective variant of this reaction is extremely attractive, as low cost or easily accessible olefins are transformed into highly versatile value-added enantioenriched aldehydes in a single step. However synthetic organic chemists interested in the synthesis of fine chemicals, both in academia and industry, have been slow to adopt this attractive protocol for the production of chiral aldehydes. This is mainly due to the fact that in the past catalysts for this reaction exhibited low activity and/or selectivity in this process. However, the last two decades have seen major advances, mainly in the development of highly effective chiral ligands, and with these developments the time has come to tackle the vastly under-explored area of asymmetric hydroformylation of more functionalised olefins. To set the scene for the research carried out during this project a brief introduction will be given which highlights the historical development of highly efficient catalysts for the hydroformylation of olefins. This will be accompanied by some examples of the use of this methodology in the synthesis of pharmaceutically relevant compounds. It should become apparent from the introduction that the asymmetric hydroformylation of functionalised olefins and in particular nitrogen containing olefins, has received very little attention despite the fact that over half of all medicinal compounds contain at least one nitrogen containing functional group. Firstly we describe hydroformylation as a useful alternative to the classical synthesis of a delicate chiral building block, namely α-formyl amides. These compounds, traditionally only available through multi-step synthetic procedures from enantiopure starting materials, have been accessed by asymmetric hydroformylation of readily accessible and in some cases commercially available acrylamides. By judicious choice of reaction conditions and selection of the appropriately active chiral ligand enantioenriched α-formyl amides (e.e. up to 82%) were produced in high yield. A comparison is made between the classical route and the hydroformylation route to illustrate the potential of this efficient transformation. We have studied the hydroformylation of enamides, a much under-studied substrate class in hydroformylation and developed knowledge of how some more functionalised 1,1- and 1-2-subtituted olefinic amides react under hydroformylation conditions. This research illustrates the work still to be done in terms of development of more active and selective catalysts for this reaction but despite limitations we developed a potential route to gamma amino aldehyde derivatives which could be used in turn in the synthesis of physiologically important gamma amino butyric acid (GABA) derivatives. We provide an example of the highly efficient and selective asymmetric hydroformylation of a bicyclic olefinic lactam, which is of industrial importance in the synthesis of carbocyclic nucleosides. We demonstrate the efficiency of this synthetic methodology by synthesising the central pharmacophore of a potent anti- HSV-1 (herpes simplex virus) carbocyclic nucleoside via a hydroformylationreduction protocol. The classical synthesis of this pharmacophore involves nine synthetic transformations to produce racemic material, whereas the hydroformylationreduction protocol produces highly enantioenriched material in just two steps. We also demonstrate some downstream chemistry of the aldehyde products showcasing the synthetic versatility of the aldehyde functionality in the production of a variety of functionalised cyclopentanes. Finally the synthesis and catalytic testing of a group of novel phosphine-phosphite ligands for use in asymmetric hydroformylation is described, one of which produces unprecedented regioselectivity and state of the art enantioselectivity in the asymmetric hydroformylation of styrene. Highly selective asymmetric hydroformylation of the other two ‘model substrates' in this reaction namely, vinyl acetate and allyl cyanide is also achieved. Having shown high activity and selectivity over these ‘model substrates' this ligand takes its place among the small group of highly active and selective ligands available for asymmetric hydroformylation and may also help to broaden the substrate scope of this efficient and atom-economic transformation.
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Desenvolvimento de novas aplicações para o glicerol, visando obtenção de materiais de interesse tecnológico / Development of new glycerol applications aiming technological materialsAlarcon, Rafael Turra 23 February 2018 (has links)
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Previous issue date: 2018-02-23 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A síntese de polímeros a partir de resíduos industriais e biomassa é o foco de muitas pesquisas realizadas atualmente, as quais buscam a sustentabilidade, viabilidade econômica e a preservação ambiental. Desta forma, um dos reagentes utilizados é o glicerol, proveniente da produção do biodiesel, este já é utilizado na síntese orgânica como solvente e como monômero na síntese de polímeros. Uma vantagem do glicerol é ser de baixo custo, considerado um composto verde, ou seja, apresenta baixo risco a saúde e ao meio ambiente. O foco do trabalho foi obter novos materiais de interesse tecnológico seguindo os conceitos da química verde e utilizando glicerol como principal reagente nas sínteses poliméricas; um dos sistemas abordados foi a fotopolimerização do glicerol com monômeros dimetacrilatos (uretano dimetacrilato, Bisfenol A dimetacrilato etoxilado, Bisfenol A dimetacrilato glicerolado e Dimetacrilato de trietilenoglicol) uma vez que é de conhecimento que o glicerol pode atuar como coiniciador radicalar na reação. Outro sistema proposto foi utilizando ácido acrílico com éster de glicerol no processo de fotopolimerização. Por fim, os dois últimos sistemas utilizam o glicerol para a obtenção de polímeros a partir de óleos vegetais. Na caracterização dos polímeros sintetizados foram utilizadas as técnicas termoanalíticas como Termogravimetria-Análise Térmica Diferencial Simultânea (TG-DTA) e Calorimetria Exploratória Diferencial (DSC), para a determinação da estabilidade térmica, etapas de degradação, polimerização térmica, transição vítrea, fusão e volatilização. Foi utilizada a espectroscopia vibracional de absorção no infravermelho médio com transformada de Fourier (MIR) para o estudo do grau de conversão dos monômeros em polímeros, identificação e análise das modificações nos sítios reacionais nos monômeros antes e após o processo de polimerização. A Microscopia Eletrônica de Varredura (MEV) foi usada para estudar a morfologia de cada polímero sintetizado. O glicerol apresentou resultados positivos na formação dos polímeros, sendo que esses podem ser utilizados como adesivos, filtros, revestimentos, adsorventes e um dos polímeros teve caraterística termoplástica. / Polymers synthesis from industrial waste and biomass is the aim of researchers nowadays that seek sustainability, economic viability, and environmental preservation. Thus, one of the used reactants is glycerol, from biodiesel production, which is used as a solvent in organic synthesis and monomer in polymers syntheses. One glycerol advantage is that it be cheap and considered a green compound, in the other words, it shows low health and environmental risk. The principal aim of this work is to get some new technological materials following green chemistry principles, and using glycerol as the principal reactant in polymer syntheses. The photopolymerization was used to get polymers from dimethacrylate monomers (urethane dimethacrylate, bisphenol A glycerolate dimethacrylate, bisphenol A ethoxylate dimethacrylate and triethylene glycol dimethacrylate) and glycerol, which could be used as radicalar coinitiator in its reaction. Another system in this work used acrylic acid and a glycerol ester in photopolymerization process. The last two system used the glycerol and vegetable oil to obtain polymers. To polymers characterization were used thermoanalytical techniques such as Simultaneous Thermogravimetry-Differential Thermal Analysis (TG-DTA) and Differential Scanning Calorimetry (DSC) to determination of thermal stability, degradation steps, thermal polymerization, glass transition, melt point, and volatilization, as well as Middle Infrared Spectroscopy (MIR) to studies about degree of conversion and identification of reaction sites and its modification after polymerization, and Scanning Electronic Microscopy (SEM) was used to study the polymer’s morphology. The glycerol showed good results in polymers formation, these polymers could be used as adhesives, filters, coatings, adsorbents and one of these polymers had the thermoplastic characteristic. / FAPESP: 2017/08820-8.
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