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Yeung, Ka Yim. "Studies on asymmetric reactions and catalysis using axially chiral 2-substituted N, N-dialkyl-1-naphthamides and p-chiral secondary phosphine oxides /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202003%20YEUNG.
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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 196-207). Also available in electronic version. Access restricted to campus users.
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Kosky, Andrew Alfred. "Interdependence of asparagine deamidation with primary and [alpha]-helical secondary structure in model peptides /." Connect to full text via ProQuest. Limited to UCD Anschutz Medical Campus, 2006.
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Thesis (Ph.D. in Pharmaceutical Sciences) -- University of Colorado at Denver and Health Sciences Center, 2006.Typescript. Includes bibliographical references (leaves 203-215). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
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Stridfeldt, Elin. "Hypervalent Iodine Reagents in Metal-Free Arylations and Vinylations : Investigation of Suitable Coupling Partners and Synthesis of New Reagents." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-141580.
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This thesis concerns the development of metal-free reactions to obtain carbon-heteroatom and carbon-carbon bonds. This is achieved by transferring carbon ligands from hypervalent iodine reagents to suitable nucleophiles. The bulk of the work presented herein concerns arylation of oxygen and nitrogen nucleophiles, using the well-known diaryliodonium salts as aryl sources. In the first project, O-arylation of the oxime ethyl acetohydroxamate was studied. It was found that electron-poor as well as electron-rich aryl moieties could be transferred successfully to this nucleophile. Furthermore, the protocol could be extended to a sequential one-pot synthesis of benzo[b]furans. This method allowed for a fast synthesis of the natural product stemofuran A and formal syntheses of other natural products. In a successive project, O-arylation of hydroxide and aliphatic alkoxides was investigated. It is known that electron-poor aryl moieties can be transferred to these nucleophiles in moderate to high yields. However, combined with more electron-rich diaryliodonium salts, a large amount of side products were formed. These were suppressed upon addition of aryne traps, suggesting that aryne pathways are competing with the desired ligand coupling. It was also observed that secondary alcohols were oxidized to the corresponding ketones. The mechanism for this oxidation was investigated and aryne pathways could be excluded. Instead we suggest that the carbinol hydrogen gets deprotonated via an internal mechanism, after the alkoxide has coordinated to the iodonium salt. Highly sterically congested alkyl aryl ethers could be obtained in high yields by combining tertiary alcohols with ortho-blocked diaryliodonium salts. Next, N-arylation of secondary acyclic amides was studied using acetanilide as the model substrate. This procedure was suitable for transfer of electron-poor as well as ortho-substituted aryl moieties, but attempts to transfer very electron-rich aryl groups were unsuccessful. On the other hand, the amides displayed a complementary reactivity, allowing phenylation of electron-rich amides. In the final project, a one-pot synthesis of the cyclic iodonium reagent vinylbenziodoxolone is presented. These compounds have not been explored as reagents earlier. Initial screenings showed that the vinyl moiety could be transferred to nitrocyclohexane with opposite regioselectivity compared to the acyclic analogue of the reagent.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.
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Marques, Joaquim Vogt. "Atividade biológica de amidas e análogos de espécies de Piper e estudos biossintéticos." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-15062009-100356/.
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Foram isoladas de Piper scutifolium e P. corcovadensis seis amidas, incluindo a piperovatina, piperlonguminina, isopiperlonguminina e corcovadina, duas inéditas (scutifoliamida A e scutifoliamida B), além de duas aristolactamas (piperolactama C e stigmalactama). A partir de P. tuberculatum foram isoladas as amidas piplartina e pelitorina e os ésteres (E)-3,4,5-trimetoxicinamato de etila (11) e 3,4,5- trimetoxidiidrocinamato de etila (12), esse último obtido pela primeira vez de origem natural. Em função da atividade biológica apresentada pelas amidas isoladas, foram sintetizadas 5-fenil-pentadienamidas e 3-cinamamidas com diferentes substituintes nos anéis aromáticos e na porção amídica. Os extratos, produtos naturais isolados e sintéticos foram submetidos a ensaios de atividade antifúngica frente Cladosporium cladosporioides e C. sphaerospermum, antimicrobiana frente à Candida albicans, C. krusei, C. parapsilosis e Cryptococcus neoformans, inibidora de acetilcolinesterase, carrapaticida frente à Boophilus microplus e citotóxica frente a linhagens tumorais humanas. Para a atividade antifúngica contra C. cladosporioides e C. sphaerospermum foi constatada maior atividade para as N-isobutil e N-pentilamidas sem substituintes no anel aromático. As N-isobutilamidas foram mais ativas como inibidores de acetilcolinesterase; contra B. microplus grande atividade foi apresentada por piperovatina, e os ensaios de citotoxicidade indicaram que o grupo 5,6-dihidropiridin- 2(1H)-ona é fundamental para a atividade. As plântulas de P. corcovadensis apresentaram em sua composição predominantemente piperovatina e assim foram utilizadas para estudos com incorporação de acetato de sódio-[1-14C] e L-fenilalanina - [U-14C] na mesma. As plântulas e calos obtidos para P. scutifolium não apresentaram produção significativa de metabólitos secundários. O estudo do metabolismo fenilpropanoídico de P. regnellii resultou no isolamento parcial da enzima responsável pela conversão de conocarpano em eupomatenóide-6.Six amides were isolated from Piper scutifolium and P. corcovadensis including piperovatine, piperlonguminine, isopiperlonguminine and corcovadine, the new scutifoliamide A and scutifoliamide B and also two aristolactams (piperolactam C and stigmalactam). From P. tuberculatum the amides piplartine and pellitorine and two esters, ethyl (E)-3,4,5-trimethoxycinnamate (11) and ethyl 3,4,5- trimethoxydihydrocinnamate (12) were isolated, this last one obtained for the first time from natural sources. Due to the biological activity observed for the natural amides, 5- phenyl-pentadienamides and 3-cinnamamides having different substituents in the aromatic ring and amide moietis were synthesized. Extracts, isolated and synthetic compounds were assayed against Cladosporium cladosporioides, C. sphaerospermum, Candida albicans, C. krusei, C. parapsilosis and Cryptococcus neoformans, inhibitory of acetylcholinesterase, against the tick Boophilus microplus and citotoxic against human cell lines. A higher activity was observed against C. cladosporioides and C. sphaerospermum for N-isobutylamides and N-pentylamides having no substituents in the aromatic ring. N-isobutylamides were very active inhibitors of acetylcholinesterase; piperovatin was the most active against B. microplus and 5,6-dihydropyridin-2(1H)-one moiety was essential as the citotoxicity is concerned. Plantlets of P. corcovadensis contained piperovatine as major compound and thus were used as model for incorporation of sodium acetate-[1-14C] and L-phenylalanine-[U-14C]. The production of secondary metabolites in plantlets and callus of P. scutifolium was not significant. The studies of phenylpropanoid metabolism in P. regnellii was addressed to partial purification and characterization of the enzyme involved in the conversion of conocarpan to eupomatenoid-6.
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Alsenani, Nawaf. "Organocatalysis using novel axially chiral secondary amines." Thesis, University of East Anglia, 2018. https://ueaeprints.uea.ac.uk/69912/.
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The field of organocatalysis has grown rapidly in the last 20 years. Moreover it is a big challenge in modern chemistry due to the rewards that can be gained from its efficiency, low cost and low toxicity. In addition, organocatalysis has many advantages in industrial chemistry it can save time and money by avoiding the use of large amounts of solvents and thus minimizing waste. This Thesis is broken down into three chapters, the first one presents a review of organocatalysis including recent updates and developments, and introduces the different organocatalyst classes, their modes of activation, and a number of examples which show the selectivity improvements obtained. The second chapter is divided into two parts. The first part descries the synthesis of certain binaphthyl organocatalysts and a description of the key steps of their synthesis: a diastereoselective Reformatsky addition and asymmetric lithiation and chloroformate/carboxylation addition steps. The second part focuses on the applications and the results obtained when these catalysts were used in aldol and Mannich reactions. The third chapter contains the experimental data for the products that are discussed in chapter two.
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Smith, Kamilah. "Mechanism and stereochemistry of the reaction of nitric oxide with secondary amines." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103033.
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The reaction of nitric oxide with secondary amines to form diazeniumdiolate anions with the structure R2NN2O2 - has been studied in order to investigate the stereochemistry and mechanism of this reaction. The stereochemical preference of the cis (Z) isomer for these compounds was proved using vibrational spectroscopy, namely infrared spectroscopy (IR) and Raman. Theoretical (B3LYP/aug-cc-pVDZ) rotation barriers for the simple diazeniumdiolate anion, Me2NN(O)=NO- are calculated in the gas phase to be 26.2 kcal/mol with the cis isomer predicted to be stabilized by only 0.5 kcal/mol compared to the trans isomer, therefore stereochemical preference for the cis is due to kinetic rather than thermodynamic control. Using vibrational spectroscopy to characterize the anion, it was determined that if the trans (E) isomer is present it represents <0.002% of the total composition.The mechanism of nitric oxide's reaction with secondary amines was elucidated using both synthetic and kinetic methods. Attempts at preparing diazeniumdiolates (NONOates) by reacting nitric oxide directly to various radical anions proved to be unsuccessful. The result of these reactions is the formation of many reaction products, many of which could not be conclusively identified.
The rate of these NO-amine condensation reactions was found to be dependent upon the solvent in which the reaction was conducted, with modest rate enhancements obtained in heterocyclic organic bases. In addition to differences in rate, the overall yield of diazeniumdiolate recovered was found to be highly dependent on solvent choice as well as amine structure.
Kinetic measurements for the formation of these compounds indicate that the rate law is multi-term and the order of reaction with respect to nitric oxide depends greatly on the concentration of nitric oxide. At low nitric oxide concentrations the dependency on nitric oxide is first order, however as the NO concentration increases the order of the reaction becomes second order in [NO].
The decomposition profile of amine derived diazeniumdiolates in aqueous media is significantly different than in organic solutions. In alkaline aqueous solutions the rate of decomposition is slow, with no significant decomposition occurring after several hours. This decomposition can be accelerated by lowering the pH. In non-aqueous solutions, the rate decomposition of the anion was determined to be comparable to the rate in neutral aqueous solutions.
Finally the equilibrium constant for the rate determining step for the reaction of nitric oxide with the secondary amine, pyrrolidine in pyridine was elucidated. The equilibrium constant for the rate limiting step was found to be 1.1 M-1.
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Chen, Yao-Jung. "Secondary amine catalyzed-oximation of cyclopentanone and basicity and reactivity of 1-azabicyclo[2.2.1]heptane /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487265555441794.
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Richards, Elinor Louise. "Tandem Michael/intramolecular aldo reactions mediated by secondary amines, thiols and phosphines." Thesis, Bangor University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273662.
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Cheng, Wei. "Dehydrogenation of Secondary Amines to Imines Catalyzed by an Iridium PCP Pincer Complex." Thesis, University of Hawaii at Manoa, 2002. http://hdl.handle.net/10125/6941.
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The PCP pincer complex, IrH2{C6H3-2,6-(PBut2)2}, catalyzes the transfer dehydrogenation of secondary amines. Dehydrogenation occurs across C-N bonds rather than C-C bonds to give imines that are obtained in good to excellent yields when the reactions are carried out in toluene solution. The regioselectivity of the dehydrogenation of aliphatic amines is stringently controlled by steric factors while dehydrogenation of aromatic amines leads to imine products favored thermodynamically by conjugated π bonds in the aromatic system. The dehydrogenation reaction has been successfully carried out in large scale (separable) with N-butylbenzylamine with acceptable separation yield. The dehydrogenation of 2,2,2',2'-tetramethyldibutylamine leads exclusively to production of the corresponding imine indicating that the catalytic reaction pathway involves the initial intermolecular oxidative addition of a N-H bond rather than a C-H bond.v, 53 leaves
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Ciubotaru, Petru. "Mechanistic aspects of the reaction of benzenesulfonyl chloride with secondary amines in aqueous media." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ39809.pdf.
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An, Feng [Verfasser], and Herbert [Akademischer Betreuer] Mayr. "Reactivity and basicity: insight into organocatalysis by secondary amines / Feng An ; Betreuer: Herbert Mayr." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1203066961/34.
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Baux, Jordan. "Utilisation d'une amine filmante pour la protection des aciers au carbone dans l'industrie nucléaire : apport de la spectroscopie d'impédance électrochimique." Thesis, Toulouse, INPT, 2018. http://www.theses.fr/2018INPT0128/document.
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La conservation du circuit secondaire des réacteurs à eau sous pression pendant les périodes d’arrêts nécessite la mise en oeuvre de conditions spécifiques afin de limiter les phénomènes de corrosion des aciers au carbone, qui composent en grande majorité ce circuit. Les méthodes de conservation impliquent une mise en oeuvre contraignante et couteuse lors des arrêts de tranche. L’injection d’amines filmantes (AF), en fonctionnement avant les phases d’arrêt, constitue une voie d’étude intéressante afin de protéger les composants en acier au carbone tout en simplifiant la mise en oeuvre de la conservation à l’arrêt. Le but de ce travail de thèse est d’étudier le comportement et l’efficacité d’une AF pour la protection des aciers au carbone dans les conditions représentatives des centrales REP. Pour mener à bien ces travaux, la spectroscopie d’impédance électrochimique a été utilisée en appui à des observations de surface par microscopie optique et microscopie électronique à balayage et à des analyses de surface par spectroscopie de photoelectrons X. Tout d’abord, des films d’AF formés sur un acier au carbone à basse température (80 °C) dans des conditions de dépôts optimisées ont été caractérisés (épaisseur, permittivité) et leurs propriétés inhibitrices de corrosion évaluées en milieu Na2SO4 à pH proche de 10. Cette première étude a permis de valider une méthode de caractérisation des films à travers l’analyse des données d’impédance à haute fréquence. Puis, cette méthode a été utilisée pour suivre et caractériser la formation de films d’AF d’une part, sur de la magnétite électrodéposée dans les conditions de dépôt optimisées, et d’autre part, sur des coupons d’acier au carbone polis dans les conditions thermo-chimiques du circuit secondaire à 120 °C, 220 °C et 275 °C en fixant la concentration en AF en solution à 2 ppm. Les suivis par impédance au cours du temps de l’acier au carbone traité avec l’AF ont permis de tester l’efficacité des films pendant une phase de conservation humide. Les résultats mettent en évidence l’influence des conditions de formation des films d’AF (température, concentration en AF, temps de traitement et nature du substrat) sur leur efficacité contre la corrosion en conservation. D’après nos résultats, seul le traitement réalisé à 120 °C a abouti à la formation d’un film d’AF pour lequel la protection de l’acier au carbone a été confirmé à l’issu d’une conservation humide de 30 jours. Les films formés sur l’acier au carbone nu à basse température ont montré une forte susceptibilité à la désorption au cours du temps, de même que pour les films d’AF déposés à 220 °C, et ce même avec une forte concentration en AF de 25 ppm. Enfin, pour les dépôts effectués à 275 °C, la cause la plus probable de la diminution de l’efficacité contre la corrosion observée entre 2 h et 24 h de traitement viendrait de la dégradation thermique de l’AF, détectée en solution au-delà de 2 h d’exposition à cette températureThe preservation of the secondary circuit of pressurized water reactors during layup periods requires the implementation of specific conditions in order to limit the corrosion phenomena of carbon steels, which constitute the major part of this circuit. These conservation methods are costly and very demanding for the operating. The injection of film-forming amines (FFA), in operation in before shutdown phases, is an interesting route of study to protect carbon steel components while simplifying the conservations. The aim of this thesis work is to study the behavior and the efficiency of an FFA for the protection of carbon steels in the representative conditions of PWRs. To carry out this work, electrochemical impedance spectroscopy was used with surface observations by optical microscopy and scanning electron microscopy and surface analysis by X-ray photoelectron spectroscopy. First, FFA films formed on a carbon steel at low temperature (80 ° C) under optimized deposition conditions were characterized (thickness and permittivity) and their corrosion inhibiting properties evaluated in an Na2SO4 medium at pH close to 10. This study allowed to validate a method for the film characterization through the analysis of the high frequency part of the impedance data. Then, this method was used to follow and characterize the FFA film formation on electrodeposited magnetite in optimized deposition conditions in one hand, and on a carbon steel under the thermo-chemical conditions of the secondary circuit at 120 °C, 220 ° C and 275 °C using FFA concentrations fixed at 2 ppm on the other hand. Impedance monitoring over time of the FFA-treated carbon steel allowed the effectiveness of the films to be followed during humid conservation. The results highlight the influence of FFA film formation conditions (temperature, FFA concentration, treatment time and nature of the substrate) on their efficiency against corrosion during conservation. According to our results, only the treatment at 120 °C resulted in the formation of an FFA film that could protect the carbon steel from corrosion in humid conservation during 30 days. The films formed on bare carbon steel at low temperature showed a high susceptibility to desorption over time, as well as for FFA films deposited at 220 °C, even with a high FFA concentration of 25 ppm. Finally, for FFA deposition made at 275 °C, the decrease of the efficiency against corrosion observed over time would come from the thermal degradation of the FFA, detected in solution beyond 2 hours of exposure to this temperature
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Callura, Jonathan C. "Activated carbon catalyzed nitrosamine formation via amine nitrosation." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52200.
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Nitrosamines have garnered increasing attention from researchers and policy makers in recent years due to potential human health implications associated with their unintentional formation in water and wastewater treatment facilities. This work addresses a crucial nitrosamine formation pathway concerning the catalysis of amine nitrosation by activated carbon materials whose use is widespread in municipal and industrial systems. Experimental results show that this catalysis is highly pH dependent, with maximum formation achieved near the pKa value for each of the secondary amines tested. This result suggests that the overall formation potential is governed by individual amine properties and their interactions with carbon surfaces, rather than solely nitrite speciation as previously reported. Formation of the most commonly studied nitrosamine, N-nitrosodimethylamine, was shown to be highly dependent on initial dimethylamine (DMA) solution concentration, with yields of approximately 0.11% of the spiked secondary amine at pH 7.5. Morpholine and dibutylamine, larger and bulkier secondary amines, formed their corresponding nitrosamines at higher yields than DMA (0.21% and 1.69%, respectively). Additionally, select tertiary amines were shown to be capable of undergoing nitrosation on the same order of magnitude as the secondary amines under neutral conditions in the presence of activated carbons. The magnitude of these results indicates that greater attention should be paid to this previously overlooked mechanism for nitrosamine formation.
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Nicolae, Toma Gabriel. "Cobalt-Catalyzed Carbon-Nitrogen Bond-Forming Reaction between Secondary Amines and N-Aromatic or Aromatic Chlorides." Kyoto University, 2011. http://hdl.handle.net/2433/142304.
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Kyoto University (京都大学)0048
新制・課程博士
博士(人間・環境学)
甲第16176号
人博第559号
新制||人||134(附属図書館)
22||人博||559(吉田南総合図書館)
28755
京都大学大学院人間・環境学研究科相関環境学専攻
(主査)教授 山口 良平, 教授 田村 類, 准教授 藤田 健一
学位規則第4条第1項該当
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吳振平 and Zhen-ping Wu. "NMR spectroscopic and kinetic studies on secondary enamines and unstable dihydroxy derivatives of heterocyclic compounds." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B3123141X.
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Wu, Zhen-ping. "NMR spectroscopic and kinetic studies on secondary enamines and unstable dihydroxy derivatives of heterocyclic compounds /." [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12352391.
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Malloy, Quentin Gerald James. "Chemical and physical characterization of secondary organic aerosol formation from select agricultural emissions." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=33&did=1871857121&SrchMode=1&sid=2&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270140114&clientId=48051.
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Fukunaga, Atsushi. "A Study on Sodium Secondary Batteries Using Ionic Liquid as Electrolytes." Kyoto University, 2016. http://hdl.handle.net/2433/215647.
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Ben, Haj Salah Khoubaib. "Substitution de la liaison amide par un triazole 1,4- disubstitué dans le but d’étudier l’impact de ce remplacement sur la structure secondaire et l’activité biologique de peptides." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS003/document.
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La réaction de cycloaddition entre un azoture et un alcyne catalysée par le cuivre (I) (CuAAC) pour former un 1,2,3-triazole 1,4-disubstitué est très utilisée dans de nombreux domaines de la chimie. Cette réaction a très vite été utilisée en synthèse peptidique notamment du fait du caractère isostère du noyau triazole et de la liaison amide. Toutefois l'impact de l'insertion d'un triazole sur la structure secondaire de peptides n'a été que faiblement exploré. Ainsi, pour étudier l'effet d'un tel remplacement nous avons choisi deux peptides modèles structurés le premier modèle est un peptide linéaire de la famille des peptaibols et le second est un peptide cyclique la tamandarine B. Dans un premier temps, nous avons optimisé une voie de synthèse de peptaibols que nous avons appliqué à l'alaméthicine F50/5 et à un analogue de la bergofungine D. Pour cela, nous avons utilisé une synthèse peptidique en phase solide sous irradiation micro-ondes en profitant d'un cocktail de réactifs efficaces contenant du diisopropylcarbodiimide comme agent de couplage et de l'oxyma. Cette méthode de synthèse a été étendue à l'obtention d'analogues silylés de l'alamethicine en substituant dans différentes positions l'acide aminobutyrique par un résidu hydrophobe et encombré : la bis-triethylsilyl-dipropylglycine (TES-Dpg). Dans la deuxième partie nous avons développé la synthèse de dipeptides à motif triazole. Puis nous avons défini les conditions réactionnelles nécessaires pour leur utilisation en SPPS et synthétisé des peptides contenant plusieurs motifs triazoles. Ces dipeptides ont ensuite été utilisés pour réaliser un scan triazole sur les deux peptaibols modèles. Les études structurales par dichroïsme circulaire, RMN et les tests biologiques de différents analogues nous permettent de conclure que le triazole affecte la structure secondaire des peptaibols et par conséquence induit une perte d'activité. Ainsi il apparaît que le concept de triazole comme isostère de la liaison peptidique doit être employé avec prudence. Dans l'optique de comprendre l'impact de triazole sur l'activité et la structure secondaire de peptides cycliques, nous avons généré des analogues simplifiés de la tamandarine B un depsipeptide cyclique d'origine marine. Nous rapportons les résultats préliminaires de cette étudeThe cycloaddition reaction between an azide and an alkyne catalyzed by copper (I) (CuAAC) to form a 1,2,3-triazole 1,4-disubstituted is widely used in many areas of chemistry. This reaction was rapidily used in peptide synthesis because of the isosteric nature between the triazole ring and the amide bond. However, impact of the insertion of a triazole on the secondary structure of peptides was only scarcely explored. Thus, to study the effect of such a replacement we chose two models of structured peptides. The first models are linear peptides of the peptaibols family and the second is the cyclic peptide tamandarin B.First, we have optimized a peptaibols synthesis that was applied to alamethicin F50 / 5 and to an analog of bergofungin D. For this we used a solid phase peptide synthesis under microwave irradiation taking advantage of the efficient cocktail consisting of diisopropylcarbodiimide as a coupling agent and Oxyma. This synthesis has been extended to silylated analogues of alamethicin by substituting in different positions the aminobutyric acid by the hydrophobic and crowded residue: bis-triethylsilyl-dipropylglycine (Dpg-TES).In the second part we have developed the synthesis of dipeptides containing a triazole motif. Then we defined the reaction conditions necessary for their use in SPPS and synthesized peptides containing several triazoles rings. These dipeptides were then used to perform a triazole scan on the two peptaibols models. The structural studies by circular dichroism, NMR and biological tests of various analogs allow us to conclude that the triazole affect the secondary structure of peptaibols and consequently induces a loss of activity. Thus it appears that the concept of triazole as isosteric of the peptide bond should be used with caution.In order to understand the triazole impact on the activity and the secondary structure of cyclic peptides, we generated simplified cyclic analogues of tamandarin B a depsipeptide of marine origin. We report the preliminary results of this study
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Bothma, Shalene Natalia. "Structural And Magnetic Investigation Of Hybrid Compound Of Saturated Primary, secondary And tertiary Organic Amines And Metal Halides." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/79178.
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Organic‐inorganic hybrid materials combine an inorganic component with an organic component at the nanoscale, while potentially retaining the properties of both components. In the current study the structural characteristics and magnetic properties of hybrid materials combining cations of saturated primary, secondary and tertiary amines with perchloridocuprate(II) and perbromidocuprate(II) anions, were studied.
The saturated cations of cyclopentylamine, cyclohexylamine, cycloheptylamine, piperazine and 1,4‐diazoniabicyclo[2.2.2]octane were chosen since the series allows for the study of the effect of the cation size, charge and saturation on the hybrid structure and also due to the scarcity of hybrid structures containing these types of saturated cations in the literature.
Perhalocuprate(II) containing hybrid materials exhibit magnetic properties due to the presence of an unpaired electron on the Cu2+ ion. At low temperatures magnetic ordering may occur via magnetic exchange pathways involving the halogeno ligands, forming ferromagnetic or antiferromagnetic materials. Identification of the magnetic exchange pathways by consideration of the crystal structure allows for the selection of a suitable theoretical quantum mechanical model to which the experimental magnetic data can be modelled, to obtain parameters like the exchange constant.
A part of the work describes the preparation of crystals of the family of hybrid materials under investigation, and the experimental techniques employed to study the structural and magnetic characteristics of the materials. The crystal structures of six novel materials are discussed in detail and compared to related structures characterised in this study, or to structures previously reported in the literature, where possible. Magnetic susceptibility data is analysed for four compounds, two of which are novel and two for structures reported previously in the literature.
By considering the novel structures characterised in this study, as well as structures previously reported in the literature, structural trends are identified. The role of saturation of the cation on the structure, as well as the effect of cation charge, is highlighted for related compounds. Robust hydrogen bonding motifs are identified for two sub‐families of structures, namely those containing isolated tetrahalocuprate(II) anions and those containing related polymeric perhalocuprate(II) anions. In addition, the magnetic properties of the family containing polymeric anions are compared.Dissertation (MSc)--University of Pretoria, 2014.
Chemistry
MSc
Unrestricted
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Huyghues-Despointes, Alexis. "Development of analytical techniques and mechanistic studies related to the thermal decomposition of Amadori rearrangement products from secondary amines." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29046.
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Standards of Amadori rearrangement products (ARP) were synthesized for the purpose of developing analytical techniques and performing mechanistic studies related to their thermal decomposition. Several synthetic strategies were explored. An HPLC analytical system with a diode array detector was coupled to a fluorometer and an electrochemical detector, in order to detect simultaneously and on-line, a wide variety of degradation products of ARPs and to follow their kinetics. The potential of such a system to analyze complex Maillard mixtures was demonstrated. The kinetics of the reaction of glucose with morpholine (a Strecker inactive analogue of proline was used in order to simplify the kinetics) to produce Amadori morpholine was studied under experimental conditions that minimize side reactions and maximize Amadori product formation. At specific time intervals, the samples were analyzed for the presence of reactants and Amadori product by the multidetector HPLC system. Color and fluorescence were also measured. The data obtained were used to calculate the rate constants for the formation and degradation of Amadori product. A mechanistic model that statistically fitted the kinetic data was proposed. To further understand the details of the decomposition mechanism of Amadori proline, different mass spectrometric experiment were performed. High resolution, linked-field scan and neutral loss experiments have indicated that 1-((2$ sp prime$-carboxyl)pyrrolidinyl)-1-deoxy- scD-fructose (Proline Amadori product) followed two main pathways of fragmentation under electron impact conditions; one initiated by the ring oxygen and the other by the amino acid nitrogen, producing two well stabilized fragment ions; oxonium and imminium ions. In addition, ortho-elimination reactions initiated by O or N-centered radical sites were shown to produce the most intense peaks and diagnostically important ions for the identification of Amadori products. However this approach can only pro
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Burrell, Emily. "The Investigation of Secondary Particle Formation Initiated by Non-Prototypical Sources and the role of Amines in the Atmosphere." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/8634.
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This dissertation is a collection of works that investigate non-prototypical sources leading to new particle formation in the atmosphere. Particles play a major role in atmospheric chemistry. For example, particles are a component of smog and are commonly found in high concentrations under conditions of atmospheric inversions. In order to reconcile the difference between measured and modeled particle concentrations new mechanisms from non-prototypical sources for particle formation need to be determined. Formation of particles has frequently been modeled using classical nucleation theory (CNT). The first step in CNT is the nucleation step where molecular clusters form. In a second step, these clusters grow into particles through coagulation or condensation. First, this research aims to improve the modeling of equilibrium constants for the formation of peroxy radical-water complexes. Failure of the harmonic approximation in the partition function for describing the low frequency vibrational modes of the complexes was explored. Instead the dissociative hydrogen bond mode using a Lennard-Jones 6-3 potential and the other low frequency vibrational modes using one- and two-fold hindered rotors was modeled. It was determined that the contribution of the two-fold hindered rotors is more important than the long-range dipole-dipole potentials and of vibration-rotation coupling. In related work, the hydroperoxy radical was investigated as a non-prototypical source of particles using high level ab initio calculations. The results indicate that the addition of an amine to the dimer increased the overall stability of complex through the increased number and strength of the hydrogen bonds. When compared to prototypical systems, sulfuric acid and methane sulfonic acid, the strength of the complex was found to be similar to the peroxy radical system. Finally, carboxylic acids, formic acid and acetic acid, were investigated as a source for new particle formation using computational and experimental techniques. Using a slow flow reactor cell particle formation was enhanced by the addition of trimethylamine. High level ab initio calculations indicate like the peroxy radicals, carboxylic acids may act as a molecular cluster in particle formation
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Šafaříková, Lenka. "EPR studium radikálových reakcí sekundárních aminů probíhajících v kapalné fázi." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-233399.
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In the framework of Ph.D. thesis the evaluation of radical reactions of four groups of secondary amines R1–NH–R2 in the presence of some selected types of agents was performed using EPR spectroscopy. First group was represented by peroxoagents (3-chloroperbenzoic acid, tBuO2 radicals), the second group involved compounds of PbIV+ (PbO2, Pb(OAc)4) functioning as hydrogen-abstracting agents. In the presence of peroxyagents the formation of corresponding aminoxyl radicals R1–NO–R2 was demonstrated. In the case of surplus of tBuO2 radicals these radicals enter the consecutive reactions which products are new types of secondary aminoxyls. By the interpretation of reaction mechanism the intermediary formation of nitrones was assumed. These function in later steps of the reaction as spin traps for tBuO2 radicals. By the study of radical mechanism of amines R1–NH–R2 initiated by PbIV+ agents was proved, that these compounds hydrogen atom not only from –NH– group under formation of aminyl radicals, but also from C–H bonds in substituents R1, R2 (the formation of C-radicals). Because both groups of the radicals formed are characterized by high reactivity, their identification was possible only using spin-trapping method. In the course of the investigation of radical reactions of secondary amines the big amount of experimental EPR spectra was obtained. These exhibited in many cases very high hyperfine structure. Due to this fact it was necessary to perform the detailed evaluation on the basis of spectral simulation. Except of some special cases using this approach the interpretation of majority of registered EPR spectra was interpreted and EPR parameters were summarized in tables.
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Ho, Danny Ka Hei. "Palladium(II)-catalysed sp 3 C–H functionalisation of hindered amines and its application in synthesis of astemizole analogues." Thesis, University of Cambridge, 2016. https://www.repository.cam.ac.uk/handle/1810/267480.
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The development of a palladium-catalysed C–H carbonylation of hindered secondary amines is described. Central to this strategy is the temporary conversion of simple ketones into hindered secondary amines that facilitates a sterically promoted palladium-catalysed C–H activation. A range of functional groups are shown to be compatible with this catalytic process, and with exclusive regioselectivity for the terminal ethyl sp 3 C–H in most cases. This method allows an overall incorporation of a carboxyl group to the b-position of terminal ketones, generating 1,4- dicarbonyl moieties which are important synthetic building blocks. The sterically promoted C–H functionalisation strategy has been employed as the key step in the synthesis of a functionalised analogue of astemizole, a pharmaceutical agent which suffers from undesired hERG activity. The increased steric bulk around the tertiary amine, coupled with introduction of a polar hydroxyl group via the C–H acetoxylation reaction, is proposed to reduce binding to the hERG channel. The hERG profile of this analogue is not yet established.
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Erupe, Mark E. "Sources and Source Processes of Organic Nitrogen Aerosols in the Atmosphere." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/196.
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The research in this dissertation explored the sources and chemistry of organic nitrogen aerosols in the atmosphere. Two approaches were employed: field measurements and laboratory experiments. In order to characterize atmospheric aerosol, two ambient studies were conducted in Cache Valley in Northern Utah during strong winter inversions of 2004 and 2005. The economy of this region is heavily dependent on agriculture. There is also a fast growing urban population. Urban and agricultural emissions, aided by the valley geography and meteorology, led to high concentrations of fine particles that often exceeded the national ambient air quality standards. Aerosol composition was dominated by ammonium nitrate and organic species. Mass spectra from an aerosol mass spectrometer revealed that the organic ion peaks were consistent with reduced organic nitrogen compounds, typically associated with animal husbandry practices. Although no direct source characterization studies have been undertaken in Cache Valley with an aerosol mass spectrometer, spectra from a study at a swine facility in Ames, Iowa, did not show any evidence of reduced organic nitrogen species. This, combined with temporal and diurnal characteristics of organic aerosol peaks, was a pointer that the organic nitrogen species in Cache Valley likely formed from secondary chemistry. Application of multivariate statistical analyses to the organic aerosol spectra further supported this hypothesis. To quantify organic nitrogen signals observed in ambient studies as well as understand formation chemistry, three categories of laboratory experiments were performed. These were calibration experiments, smog chamber studies, and an analytical method development. Laboratory calibration experiments using standard calibrants indicated that quantifying the signals from organic nitrogen species was dependent on whether they formed through acid-base chemistry or via secondary organic aerosol pathway. Results from smog chamber reactions of amines with ozone, nitrogen oxides, nitrate radical, and nitric acid showed that the secondary organic aerosol pathway was more plausible than acid-base chemistry, thus making the contribution of the organic nitrogen species to the total aerosol mass in Cache Valley significant. Gas phase and aerosol products formed from the smog chamber reactions were identified and used to devise reaction mechanisms. Finally, an ion chromatographic method for detecting and quantifying some key organic nitrogen species in aerosol was developed and tested.
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Yamamoto, Takayuki. "A study on tin-based negative electrode materials for sodium secondary batteries using Na[FSA]-K[FSA] inorganic ionic liquid." Kyoto University, 2016. http://hdl.handle.net/2433/215648.
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Chen, Chih-Yao. "A study on positive electrode materials for sodium secondary batteries utilizing ionic liquids as electrolytes." Kyoto University, 2014. http://hdl.handle.net/2433/192207.
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Ortmayer, Mary. "Structure and function of an unusual heme dependent secondary amine oxidase." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/structure-and-function-of-an-unusual-heme-dependent-secondary-amine-oxidase(2171f7d9-a40d-4605-85ff-452c4f30b551).html.
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The orphan enzyme “secondary amine monooxygenase (SAMO)” catalyses the N- dealkylation of dimethylamine (DMA) to methylamine and formaldehyde using NADPH and oxygen. It is described in the literature as a heme-dependent monooxygenase enzyme, similar in terms of the overall reaction catalysed to the well- characterised cytochrome P450s (CYPs). However, the SAMO heme is without the essential CYP thiolate ligand, featuring the more common histidine-ligation instead. During a study of bacterial operons containing H4F-binding modules, the genes encoding for SAMO were discovered. It was found that four genes αβγδ encode for the heterotetrameric SAMO. While sequence similarities indicate α encodes for an H4F- aminomethyltransferase module, and γ for an NADPH/FMN/2Fe2S reductase module, the function of β and δ genes was unclear. Spectral analysis of the Rhizobium etli CFN 42 δ-subunit reveals it to be the heme-binding domain (δRe), with the cofactor-free β- subunit responsible for enhanced DMA binding by the βδRe complex. DMA has the highest affinity for ferrous-oxy δRe, indicating close interaction between the dioxygen and DMA. Both δRe and βδRe have a positive redox potential supporting formation of a relatively stable dioxygen complex. Holoenzyme SAMO from Pseudomonas mendocina ymp (αβγδPm) demonstrates DMA dependent NADPH oxidation and formaldehyde production, but is inherently unstable. The crystal structure of SAMO heme domain from P. mendocina (δPm) reveals a heme-binding PAS domain. Capitalising on the 1.9 Å ternary complex structure with DMA and nitric oxide, a model of the SAMO catalytic mechanism was proposed. Conserved active site residues including Trp180 and Glu266 (involved in substrate binding), in addition to Arg224 were mutated, each rendering αβγδPm inactive. It is proposed that the positively charged amine substrate works in concert with conserved Arg224 residue to create a polarised active site, supporting heterolytic cleavage of the O-O bond. However, unlike other heme enzymes SAMO lacks a strong electronegative proximal ligand. In view of this, it is proposed SAMO catalyses an oxidase-type reaction, leading to a transient iminium species, in the absence of substrate oxygen insertion. To the best of current understanding, SAMO appears to be a novel type of PAS domain that performs an oxidase reaction with oxygen activation facilitated by the secondary amine substrate.
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Dufour, Éric. "Contribution a la connaissance de la structure d'une cysteine proteinase : purification, sequence en acides amines et structure secondaire de la cathepsine l de foie de poulet." Clermont-Ferrand 2, 1988. http://www.theses.fr/1988CLF21109.
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Lecomte, Catherine. "Le métabolisme intermédiaire chez le rat après exposition à l'hypoxie intermittente : étude de l'utilisation et des effets du malate de citrulline." Lyon 1, 1993. http://www.theses.fr/1993LYO10149.
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Les modifications metaboliques consecutives a l'exposition a l'hypoxie intermittente (ehi: 2. 2 h/j; 5 jours; 4500 m) chez le rat ont ete etudiees au niveau de l'organisme entier et au niveau cellulaire (hepatocytes isoles). Les effets de l'administration aigue ou chronique (5 jours) de malate de citrulline (mc), substance preconisee comme antiasthenique ont ete examines chez les animaux ehi et controles. Les productions de glucose et d'uree a partir de substrats (2 mm) sont legerement inferieures dans les hepatocytes isoles de rats ehi vs controles (ns); la difference devient significative avec le lactate (moins 20%) en tenant compte du contenu cellulaire en atp. L'ehi chez le rat aboutit a une reduction des capacites gluconeogeniques et ureogeniques des hepatocytes isoles et peut representer un modele experimental d'etude de gluconeogenese et d'ureogenese diminuees. Ces voies sont importantes a examiner dans certaines situations, en particulier lors de l'apparition de la fatigue. A cet egard, les rats ehi presentent un comportement explorateur diminuant leur temps de maintien sur le rota-rod (moins 46%, ns) par rapport aux controles, mais la reponse a des epreuves de nage, 18 heures apres la derniere exposition, n'est pas differente dans les deux groupes d'animaux. L'etude de la charge ip (3,2 mmol/kg) de mc montre une utilisation en 4 a 7 heures. A partir des courbes moyennes, les parametres cinetiques pour le malate et la citrulline ont ete obtenus. L'injection de mc s'accompagne d'une augmentation de la glycemie, de l'uremie et de la lactatemie. L'augmentation statistiquement significative au seuil de 5% du temps de nage (lest 5%) chez les rats traites au mc par rapport aux non traites (plus 25%) suggere un effet positif de l'administration de mc dans nos conditions experimentales qui pourrait etre la consequence de son utilisation metabolique
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Guelzim, Najoua. "Régulation du métabolisme secondaire de l'arginine et de la cystéine par l'acide alpha-linolénique. Implication dans la physiopathologie du syndrome métabolique." Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00781861.
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Si l'intérêt nutritionnel des acides gras polyinsaturés (AGPI) n-3 dans la prise en charge et la prévention des dysfonctions associées au syndrome métabolique, est bien établi. Les mécanismes d'action spécifiques sous-jacents aux effets bénéfiques de cette famille d'acides gras sont encore en cours d'étude. L'objectif de ces travaux était d'explorer le rôle de l'acide alpha-linolénique ALA ou 18 :3 n-3, dans la modulation des voies affectant l'homéostasie de molécules bioactives dérivant du métabolisme secondaire des acides aminés (le monoxyde d'azote -NO- et le glutathion). L'hypothèse sous-jacente est que ces modulations pourraient expliquer, du moins en partie, le rôle des AGPI n-3 dans le maintien des fonctions biologiques contrôlées par ces métabolites (telles que la fonction endothéliale et le statut oxydant) et impliquées de près dans la physiopathologie du syndrome métabolique. Notre intérêt a porté particulièrement sur la voie de régulation génique via le PPARα et sur son implication dans le contrôle des gènes du métabolisme des acides aminés par l'ALA. Nous avons exploré chez la souris de type sauvage et invalidée pour le PPARα, l'effet de l'apport alimentaire d'ALA dans le cadre de régime normo- ou hyper-lipidiques sur les voies du métabolisme secondaire de l'arginine et de la cystéine. En parallèle nous nous sommes focalisés sur les effets de l'ALA au niveau vasculaire en utilisant un modèle de cellules endothéliales bovines en cultures. De ce travail de thèse s'est dégagé que l'ALA module effectivement le métabolisme secondaire de l'arginine et de la cystéine. L'apport d'ALA (à hauteur de 11% et 42% de l'apport énergétique) augmente la production de NO sans affecter l'expression hépatique des enzymes contrôlant l'utilisation de l'arginine (NOS et ARG). L'apport d'ALA (11%) augmente le pool hépatique du glutathion, alors que les plus forts apports d'ALA (42%) modulent l'expression des principales enzymes impliquées dans les voies d'utilisation de la cystéine (γGCL et CDO). Le PPARα ne semble pas être directement impliqué dans les effets observés de l'ALA, néanmoins, l'invalidation du PPARα rend le métabolisme secondaire des acides aminés plus sensible à la nature des acides gras alimentaire. Une meilleure biodisponibilité du NO et du glutathion suite à l'apport alimentaire d'ALA serait bénéfique pour la physiopathologie du syndrome métabolique. Il semble donc intéressant, à l'issus de ce travail, d'élaborer des études nutritionnelles validant ces effets de l'ALA chez l'homme dans une perspective de recommandations nutritionnelles.
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Saliba, Carlos Alberto Mattos. "Evolution de la mouillabilite en fonction de l'adsorption du petrole et de ses fractions approche par la methode des angles de contact dynamiques." Paris 6, 1996. http://www.theses.fr/1996PA066282.
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La mouillabilite d'un reservoir est tres importante pour la recuperation du petrole lors de la mise en exploitation par injection d'eau ou par d'autres procedes. Elle est un parametre-cle pour controler la distribution des fluides dans le milieu poreux et le flux multiphasique. Neanmoins, la mouillabilite a l'eau d'un reservoir peut etre alteree du fait de l'adsorption de tensioactifs naturels (asphaltenes et resines) presents dans le petrole. Cette adsorption peut reduire la recuperation du petrole. Dans ce travail, nous avons etudie l'influence de l'adsorption de molecules modeles (pyridine et benzoquinoleine), de l'huile brute et de ses fractions lourdes (resines et asphaltenes) sur le changement de mouillabilite de surfaces mouillables a l'eau (verre et quartz). La technique de wilhelmy permet de quantifier la preference de la surface pour l'eau ou pour l'huile brute. Les resultats montrent qu'en conditions ambiantes l'adsorption depend de la concentration, du temps d'interaction adsorbant/adsorbat, du ph, du type de solvant, de l'etat cristallin du substrat, de la concentration en sel et de la nature de la phase liquide environnante (aqueuse ou huile). Par contre, la presence d'un film d'eau sur la surface solide n'a pas une influence significative sur ce phenomene
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Membrat, Romain. "Réactions de transfert d'hydrogène catalysées par les complexes de palladium et de platine associés aux ligands phosphinito-acide phosphineux." Electronic Thesis or Diss., Aix-Marseille, 2019. http://theses.univ-amu.fr.lama.univ-amu.fr/190719_MEMBRAT_386crd806cefe861cbrkq829aijwx_TH.pdf.
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La notion de transfert d'hydrogène métallo-catalysé étudiée dans ce manuscrit consiste à générer un hydrure métallique actif à partir d'un donneur d'hydrogène (alcool) et à le transférer vers un produit insaturé dans un objectif d'augmentation de la complexité moléculaire. Une large gamme de produits peut être synthétisée grâce à ce concept et à ses diverses variantes. Le ligand phosphinito-acide phosphineux (PAP) qui est un ligand chargé négativement, permet de former des complexes robustes avec le palladium ou le platine et de générer en présence d'un alcool des hydrures métalliques remarquablement actifs. Dans la première partie de ce travail, un nouveau système d'oxydation d'alcool en milieu anaérobie particulièrement chimiosélectif a été développé. Les études complémentaires mises en œuvre ont permis une bonne compréhension du mécanisme de transfert d'hydrogène. Elles ont également mis en lumière l'intéressante aptitude du ligand PAP à auto-adapter ses propriétés électroniques spécifiquement à chaque étape d'un cycle catalytique. Dans un deuxième temps, une cascade réactionnelle oxydation - double activation de liaison C(sp3)-N débouchant sur la production d'amines primaires libres sans purification a été présentée. Il a été démontré à cette occasion que les complexes M/PAP pouvaient jouer le rôle d'acides de Lewis faible. Enfin, un processus de transfert d'hydrogène énantiosélectif a été étudié à travers l'isomérisation énantiosélective des alcools allyliquesThe notion of metal catalyzed hydrogen transfer presented in this manuscript relies in generating an active metal hydride from an hydrogen donor (alcohol) and transferring it toward an unsaturated product with a view to molecular complexity increasing. A broad variety of product could be targeted with this concept and its variants. The phosphinito-phosphinous acid ligand which is negatively charged ligand is capable to generate strikingly active palladium and platinum hydride. In the first part of this work, a new anaerobic alcohol oxidation system with remarkable properties of chemioselectivity has been developed. Complementary studies have allowed a good understanding of the hydride transfer mechanism. Moreover it highlighted the interesting ability of the PAP ligand to self adapt its own electronic properties specifically to each steps of the catalytic cycle. In a second stage, a cascade process oxidation - double C(sp3)-N bond activation has been presented. It has been shown that M/PAP complexes could act as a weak Lewis acid. Finally, an enantioselective version of hydride transfer processes has been studied through enantioselective isomerization of allylic alcohols. The effect of the combination of a P - stereogenic ligand and new secondary chirality inductors (central chirality borne by the X-type ligand and inherent chirality borne by a supramolecular C1 symmetric moiety) has been evaluated
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BOUAYAD, ZOHEIR. "Ouverture nucleophile d'aziridines fonctionnalisees par des composes a methylene actif : synthese de pyrrolidones-2 fonctionnalisees." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2S884.
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Riondel, Alain. "Étude de la réactivité de carbonates et de carbamates chlorés vis-à-vis de nucléophiles. Formation d'anions à l'aide des bases complexes." Nancy 1, 1988. http://www.theses.fr/1988NAN10505.
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Pop, Laura Ancuta. "Synthèse stéréosélective d'hétéroaryl alcools et alanines." Phd thesis, INSA de Rouen, 2011. http://tel.archives-ouvertes.fr/tel-00940020.
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Cette thèse présente la synthèse stéréosélective de plusieurs nouveaux acides aminés et alcools secondaires en utilisant la biocatalyse. Le travail est divisé en deux parties principales. La première partie est consacrée à la synthèse stéréosélective des alanines hétéroaryles en utilisant deux différents biocatalyseurs avec le même énantiopréférence, l'aminocatalyse I et la levure de boulanger (Saccharomyces cerevisiae). A l'aide de ces deux biocatalyseurs, les L-alanines ont été obtenus avec des excès énantiomériques et rendements élevé. La deuxième partie est consacrée à la synthèse des deux énantiomètres des alcools secondaires (hétéro)aryles en utilisant les lipases comme biocatalyseurs. Cette partie est divisée en deux sous-chapitres, un pour la synthèse stéréosélective de différents (thiazole-2-yl) - méthanols C-substitués et leurs dérivés acylés. Ces composés ont été obtenus par l'acylation enzymatique stéréosélective des alcools racémiques et par l'hydrolise enzymatique de leurs dérivés acylés.
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Schwarz, Christina. "Rearrangements of secondary methylenecyclopropyl amides." 2004. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=94909&T=F.
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McKay, Sonya L. "Investigations of aromatic-aromatic interactions using secondary and tertiary amides." 2001. http://www.library.wisc.edu/databases/connect/dissertations.html.
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Shu, Hui-Ti, and 許輝地. "Preparation of N-aryl-6-hydroxyhexanamidesvia ring-opening of tetrahydrofuran with lithiated secondary amides." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/60254935363471760197.
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碩士高雄醫學大學
醫藥暨應用化學研究所碩士在職專班
95
In this thesis, the preparation of N-aryl-6-hydroxyhexanamides from the ring-opening of THF with lithiated secondary amides was described. The starting materials , N-arylacetamides , prepared from acylation of various anilines , were treated with n-butyl lithium at -78℃ in the presence of BF3-etherate in anhydrous THF to give various N-aryl-6-hydroxyhexanamides in moderate yields.
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Lee, Namkyu. "Enantioselective protonations of enolates using optically pure secondary amines." 1992. http://catalog.hathitrust.org/api/volumes/oclc/28638030.html.
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Böttcher, Jark [Verfasser]. "Structure-based development of secondary amines as aspartic protease inhibitors / vorgelegt von Jark Böttcher." 2009. http://d-nb.info/993465374/34.
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Li-Yu, Huang, and 黃立宇. "Synthesis of Ruthenium Formyl Complex and Coupling Reactions between Alkynes and Secondary Amines via Ruthenium Complexes." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/74866584347956683960.
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碩士臺北市立教育大學
應用物理暨化學系化學組碩士班
100
The complex Tp(PPh3)(Ph2C=NH)Ru-Cl {Tp = HB(pz)3, pz = pyrazolyl} reacts with propargyl alcohol (HCα≡Cβ-CγH2OH) and results in the formation of the ruthenium carbonyl complex and a formaldehyde via Cα≡Cβ and Cβ-Cγ bonds cleavage. The C=C bond is oxidized and forms the formyl group.
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Cheng, Lin-Chieh, and 鄭琳潔. "Cu-Catalyzed Aerobic Oxidation in the Synthesis of Quinolinium Salts from Secondary Amines, Alkynes, Formaldehyde and Acid." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/dg5crz.
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碩士國立清華大學
化學系所
106
Substituted heterocyclic nitrogen salts are versatile building blocks for a number of natural products and bioactive motifs. Herein, we report a novel and convenient process to synthesize quinolinium salt derivatives by Cu-catalyzed aerobic oxidative coupling of secondary amine, alkyne and formaldehyde. The reaction proceeds via acid induced N,N-disubstituted iminium ion formation followed by nucleophilic addition of alkyne, annulation, and copper-promoted oxidation. This method features an economical catalyst, one pot process, ambient reaction temperature and short reaction time.
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Ho, Sheng-kai, and 何聖凱. "Effects of Secondary Amines on the aggregation properties of polyaniline solutions investigated by Coarse-Grained Molecular Dynamics Simulation." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/05319638061586207410.
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碩士國立中正大學
化學工程所
95
At two different length scales, we introduce the methods of molecular dynamics simulation and establish new potential functions for coarse-grained simulations. When adding secondary amines, such as azetidine, pyrrolidine and piperidine, in the solution of polyaniline (PANI)/N-methyl-2-pyrrolidnone (NMP), the motion and structure of PANI are systematically investigated using the proposed simulations. From the literature, the chains of PANI, which bears hydrogen bonds, tend to aggregate in NMP. When adding secondary amines in the solution of PANI/NMP, the coils of PANI aggregates swell and become looser according to the calculated radii of gyration. This property indicates that PANI may better disperse in NMP by adding secondary amines.
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Qiu, Chong. "Atmospheric Aerosols Aging Involving Organic Compounds and Impacts on Particle Properties." Thesis, 2013. http://hdl.handle.net/1969.1/149291.
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In the first part of this dissertation, we study the aging of soot, a representative type of primary aerosols, in the presence of OH-initiated oxidation products of toluene. Monodisperse soot particles are introduced into an environmental chamber where toluene is oxidized by OH radicals. The variations in soot particle properties are simultaneously monitored, including particle size, mass, organic mass faction, hygroscopicity, and optical properties. The changes in particle properties are found to be largely governed by the thickness of the organic coating that is closely related to reaction time and initial reactant concentrations. Derived from particle size and mass, the effective density increases while dynamic shape factor decreases as the organic coating grows, suggesting a compaction of the soot morphology. As the organic coating grows, the particles become more hygroscopic and have enhanced light scattering and absorption.
The second part discusses the potential reactions between amines and some aerosol constituents and alteration of aerosol properties. The reactions between alkylamines and ammonium sulfate/bisulfate have been studied using a low-pressure fast flow reactor coupled to a mass spectrometer at 293 K. Alkylamines react with ammonium sulfate/bisulfate to form alkylaminium sulfates, suggesting the existence of alkylaminium salts in particle phase. We have extended our study to characterize the physicochemical properties of alkylaminium sulfates. The hygroscopicity, thermostability, and density of five representative alkylaminium sulfates have been measured by an integrated aerosol analytical system. All alkylaminium sulfate aerosols show monotonic size growth when exposed to increasing relative humidity. Mixing ammonium sulfate with alkylaminium sulfates lowers the deliquescence point corresponding to ammonium sulfate. Alkylaminium sulfates are thermally comparable to or more stable than ammonium sulfate. The densities of alkylaminium sulfate particles are lower than that of ammonium sulfate.
Our results suggest that the organic compounds can effectively alter the composition and properties of atmospheric aerosols, considerably influencing the impacts of aerosols on air quality, climate forcing, and human health.
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"Hybrid tertiary phosphine/secondary amide and amine ligands. their synthesis and coordination chemistry with platinum, palladium, rhodium, and iridium (phosphorus, nitrogen, amido)." Tulane University, 1985.
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The tertiary phosphine/secondary amide and amine hybrid ligands o-(diphenylphosphino)-N-phenylbenzamide (P(CO)NHPh), o-(diphenylphosphino)-N-benzoylaniline (PNH(CPhO), o-(diphenyl- phosphino)-N-phenylbenzylamine (PCNHPh), and o-(diphenyl- phosphino)-N-benzylaniline (PNHBz) have been synthesized and characterized. PNH(CPhO) undergoes N-H oxidative addition with IrL(,2)Cl (L = 2PPh(,3), 2AsPh(,3), 1,2-(Ph(,2)P)(,2)C(,2)H(,4)) to give a mixture of two isomers of the Ir(III) amido hydride(' )Ir PN(CPhO) L(,2)(H)Cl. The possible structures of these isomers are discussed on the basis of their spectroscopic properties (('31)P nmr, ('1)H nmr, and infrared). The reactions of IrL(,2)Cl and the other hybrid ligands give similar results. The oxidative addition reaction of the N-H moiety of a secondary benzamide or aniline and IrL(,2)Cl does not occur in the absence of the chelate effect. Neither PNH(CPhO) nor P(CO)NHPh undergo N-H oxidative addition with either M(cod)Cl (,2) or M(cod)(THF)(,2) - ClO(,4) (M = Rh, Ir; cod = 1,5-cyclooctadiene); instead M(I) phosphine complexes are obtained. The hybrid ligands were used to prepare the chelate-stabilized amido complexes (cod)M(P N)(' )(M = Rh, P(' )N(' )= PN(CPHO), P(CO)NPh; M = Ir, P N = P(CO)NPh) and Ir PN(CPhO) (cod)H(Cl).(' )The properties of these rhodium and iridium complexes are discussed. PNH(CPhO) and P(CO)NHPh coordinate to M(II) (M = Pd, Pt) via the phosphorus atom to give the complexes ML(,2)Cl(,2) (L = hybrid ligand). Deprotonation of the nitrogen atom of these complexes gives the bis(amido) complexes M(P(' )N)(,2) (P N(' )= PN(CPhO), P(CO)NPh). The Pd(II) bis(amido) complexes were also prepared by the reaction of the hybrid ligands and Pd(,2)(dba)(,3) (dba = dibenzylideneacetone). The cyclometallated amido complexes(' )M o-Ph(,2)PC(,6)H(,4)NC(O)C(,6)H(,4) PNH(CPhO) (M = Pd, Pt) have been synthesized. The structure of the Pt complex was determined by a single crystal X-ray diffraction study. The solid state molecular structure is best described as a square pyramid with the NH moiety of the PNH(CPhO) ligand residing in the apical position. A short Pt-H distance of 2.46 A was found, and this interaction may be important in the H/D exchange reaction between the NH proton of these amido complexes and deuterated solvents. The reactivity of the palladium and platinum amido complexes was examinedacase@tulane.edu
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Lauzon, Caroline. "Synthèse d'amines [alpha]-chirales tertiaires et d'alcools secondaires chiraux via l'addition énantiosélective de dialkylzinciques ; Synthèse de N-phosphinoylimines via la réaction de Kresze." Thèse, 2006. http://hdl.handle.net/1866/16796.
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Cluzeau, Jérôme. "Développement de méthodes de synthèse pour les acides aminés indolizidin-9-ones substitués et utilisation des acides aminés azabicycloalcanes en tant que mimes peptidiques." Thèse, 2004. http://hdl.handle.net/1866/14353.
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Kang, Jee Eun. "Novel bioinformatics programs for taxonomical classification and functional analysis of the whole genome sequencing data of arbuscular mycorrhizal fungi." Thèse, 2018. http://hdl.handle.net/1866/21799.
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