Dissertations / Theses on the topic 'Méthyl éther – Synthèse (chimie)'
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Théry, Hétreux Raphaële. "Analyse de faisabilité, synthèse et conception de procédés de distillation réactive." Toulouse, INPT, 2002. http://www.theses.fr/2002INPT023G.
Mammeri, Malika. "Synthèses de la 7-méthyl-2-tétralone et du 2-méthoxy-6-méthyl naphtalène. Synthèse d'acides α, β-éthyléniques de configuration cis." Rouen, 1998. http://www.theses.fr/1998ROUES085.
Lecouve, Jean-Pierre. "Organométalliques vinyliques à fonction carbonylée masquée : application à la synthèse du rétinal." Rouen, 1986. http://www.theses.fr/1986ROUES016.
Bleton, Jean. "Synthèse d'alcynes disubstitués : étude de la transposition de Fritsch-Buttenberg-Wiechell." Paris 11, 1988. http://www.theses.fr/1988PA112203.
Behloul, Chakib Rafik. "Méthodes de conception de réacteurs multifonctionnels (réacteur-échangeur-séparateur) : application à la synthèse directe de DME à partir de CO₂ et d’H₂." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0249.
The depletion of resources and the accumulation of pollutant gases in the atmosphere are nowadays of growing concern. The current energy transition requires that certain material and energy transformation processes be partially modified or profoundly reconsidered to fit more sustainable operating conditions. Low-carbon electricity and hydrogen can substitute fossil fuels, leading to an energy mix with a low greenhouse gas (GHG) footprint. In addition to hydrogen, the production of alternative fuels and high value-added products is another way to support the energy transition.Looking for optimal, sustainable and economical processes is therefore a major challenge that process engineers are facing. The present work has thus focused on the intensification of mass and energy transformation processes, through multifunctional units, which take advantage of the synergies between elementary functions of transformation (reaction, transfer, separation, etc.) within an intensive equipment. The concept of multifunctional reactors, coupling several elementary functions, has been a real success when historical demonstrators were created (Eastman-Kodak process, etc.), but their implementation has not been generalized, due to a lack of practical design methodology.This work focuses on the implementation of some intensification methodologies to understand and improve the performance of a process involving balanced exothermic reactions. The dimethyl ether (DME) direct synthesis from CO₂ and H₂ is considered as a case study. Different exploratory ways for the DME direct synthesis process development have been investigated based on modeling and simulation. Reactor- Heat exchanger, multifunctional reactor (reactor-heat exchanger-membrane separator), hybrid elementary block processes and a process involving the cooled reactor in a conventional process environment in the presence of additional unit operations and recycle loop are studied from different angles. Different optimization cases and strategies have been addressed which differ by the decision variables and the solving method. The different methodologies applied have demonstrated the relevance of the solutions obtained and the opening towards process innovation.At the equipment level, the profiles optimization represents the heart of the methodology. The results demonstrate the potential of multifunctional reactors: a CO₂ conversion per pass of 98%, a DME yield of 95% and the possibility to remove a distillation column are obtained. In order to assess the maximum achievable performance in a multifunctional reactor, a hybrid process of elementary blocks has been optimized. At the process scale, the reactor behavior has been studied to further understand the impact of the reactor integration in a recycle loop and to estimate the local and global effects on the multiple performance criteria. Based on various criteria (overall DME yield, overall CO₂ conversion, TRL, etc.), the comparison of the different designs revealed that a reduction of the equipment number by a factor of 11 is possible in the case of a multi-functional reactor choice
Bidois, Séry Laure. "Nouvelle méthode d'accès aux composés aromatiques fluorés. Alkylations et aldolisations d'énolates préparés à partir d'énoxysilanes." Rouen, 1995. http://www.theses.fr/1995ROUES029.
Magnet, Serge. "Fonctionnalisation d'un latex styrène-acrylate de butyle par le méthyl acrylamido glycolate méthyl éther et par le méthacrylate de glycidyle : relation procédé de synthèse-structure - propriétés." Lyon 1, 1989. http://www.theses.fr/1989LYO10183.
Satrallah, Ahmed. "Etude des produits de condensation de l'isopropyl-4 méthyl-3 phénol avec le formaldéhyde : synthèse et propriétés de calixarènes asymétriques." Lyon 1, 1988. http://www.theses.fr/1988LYO10172.
Hadj, Ali Kamal. "Étude cinétique de l'oxydation et de l'auto-inflammation en milieux gazeux homogène pauvre et ultra pauvre de carburants de substitution issus de la biomasse." Lille 1, 2007. http://www.theses.fr/2007LIL10004.
Barbarotto, Marie. "Synthèse de motifs "2-méthyl-1,3-aminoalcools" par réaction de type Reformatsky asymétrique : vers la synthèse totale du (+)-triènomycinol." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00767096.
Guillerm, Brieuc. "Synthèse et étude physico-chimique de copolymères amphiphiles à base de poly(2-méthyl-2-oxazoline)." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20102/document.
This manuscript deals with the synthesis of amphiphilic diblock copolymers obtained by the coupling of both hydrophobic and hydrophilic homopolymers. The copolymers were achieved in two steps. On the one hand, homopolymers poly(2-methyl-2-oxazoline) P(MOx)s and poly(tert-butyl acrylate)s (P(At-Bu) were synthesized by cationic ring opening polymerization (CROP) and by Reversible Addition-Fragmentation Transfer (RAFT) polymerization and atom transfer radical polymerization (ATRP), respectively. Finally, amphiphilic diblock copolymers were achieved by Huisgen's cycloaddition. Physical chemistry studies in water proved the formation of aggregates. The latter had a spherical morphology, sizes below 100 nm and critical aggregation concentration around 10-6 mol.L-1.Knowledge acquired on the synthesis and the study of amphiphilic block copolymers led to the development of poly(-caprolactone)-g-poly(2-methyl-2-oxazoline) (PCL-g-P(MOx)) amphiphilic graft copolymers, made of a hydrophobic PCL grafted with hydrophilic P(MOx) moieties. The study of aqueous solution of such copolymers showed the formation of aggregates with characteristics close from those obtained for the diblock copolymers. Another interesting point is that P(MOx) permitted the solubilization of PCL in water.The reported work illustrated the importance of macromolecular chemistry for the obtaining of amphiphilic copolymers with controlled molecular weight and narrow molar mass distributions which self-assemble in water. Such kind of materials could be used in the biomedical field
Breton, Gilles. "1. Synthèse et étude d'organométalliques en série pyridinique organotitaniques organomercuriques organomagnésiens. 2. Mise au point d'une synthèse de la 2-méthyl-3-trifluorométhylaniline." Rouen, 1999. http://www.theses.fr/1999ROUES057.
Karoui, Hakim. "Synthèse d'une nouvelle nitrone phosphorylée : la 5-diéthoxyphosphoryl-5-méthyl-1-pyrroline N-oxyde (DEPMPO). Applications au piégeage in vitro et in vivo des radicaux libres centrés sur l'oxygène." Aix-Marseille 3, 1994. http://www.theses.fr/1994AIX30019.
Cai, Mengdie. "Design of novel hybrid catalysts for direct synthesis of Dimethyl ether from syngas." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10082/document.
A series of novel bi-functional catalysts Cu-ZnO-Al2O3/ZSM-5 were prepared by physical mixing method, characterized, and evaluated in a fixed-bed reactor for direct dimethyl ether (DME) synthesis from syngas. The catalytic activity for DME synthesis was attributed to copper metal sites and zeolite acidity. Zeolite crystals of smaller size lead to higher catalyst activity. The catalyst deactivation was strongly affected by the acid sites on the external surface of zeolites. Higher external acidity of ZSM-5 results in fast catalyst deactivation. Copper sintering and migration seem to be principal mechanisms of deactivation. The acidic sites on the external surface of zeolite were selectively neutralized by silylation with tetraethyl orthosilicate. Consequently both catalyst stability and DME productivity were significantly improved. Carbon dioxide is the major undesirable byproduct of direct DME synthesis. It forms by Water-Gas-Shift (WGS) reaction. The promotion of bi-functional Cu-Zn-Al/HZSM-5 catalysts with tin slows down the WGS and increases the selectivity to DME
Bénard, Didier. "Nouvelle approche en synthèse peptidique : voie non isohypsique : oxydation chimique et ammoxydation catalytique de la méthyl-4 pyridine." Rouen, 1986. http://www.theses.fr/1986ROUES006.
L'Hospital, Valentin. "Développement et optimisation de catalyseurs à base de cuivre pour la synthèse de méthanol et de diméthyléther à partir de CO2." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF028/document.
Reducing CO2 emissions, the main greenhouse gas, is one of the major challenges of our current era. Many measures already exist but are still insufficient. It is in this context that the ANR project called DIGAS was funded. During this work, catalytic materials composed of CuO/ZnO/ZrO2 were developed by classical coprecipitation and tested under a pressure of 50 bar for the methanol synthesis from CO2 hydrogenation. Then, these catalysts were optimized using a system developed in the laboratory: microfluidic continuous synthesis. It has made the catalysts more homogeneous and thus more efficient. The most efficient catalyst was subsequently coupled to a ZSM5 zeolite to allow direct dimethyl ether (DME) synthesis from the CO2 hydrogenation. In the case of methanol as well as for DME synthesis, the developed catalysts are competitive and more efficient than the catalysts currently on the market
Cázares, Cortés Esther Del Carmen. "Synthèse de nanogels biocompatibles et multi-stimulables pour la libération contrôlée d'une molécule modèle par hyperthermie magnétique et photothermie." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066290/document.
Hybrid nanogels, composed of thermoresponsive polymers and inorganic responsive nanoparticles, such as magnetic nanoparticles (NPMs) and gold nanorods (AuNRs) are highly interesting for biomedical applications. Their polymeric matrix makes them able to uptake and release high quantities of drugs, whereas nanoparticles can generate heat when exposed to an alternating magnetic field (AMF) for NPMs, and to a near-infrared light for AuNRs. This thesis manuscript focuses on the synthesis and the characterization of biocompatible, pH- and thermoresponsive nanogels, based on oligo(ethylene glycol) monomers (OEGMAs), methacrylic acid (MAA) and encapsulating NPMs and/or AuNR for remotely triggered doxorubicin (DOX, anticancer drug) release, by magnetic hyperthermia or phothothermia. Hybrid magnetic, plasmonic and magneto-plasmonic nanogels were synthesized. Theses nanogels have a hydrodynamic diameter between 200 and 500 nm and a volume phase transition temperature (VPTT) from 30 to 54°C. The nanogels’ swelling-deswelling behavior can be induced by several stimuli (temperature, pH, AMF, NIR-L). These results demonstrate that MagNanoGels are excellent nanocarriers for enhancing cellular internalization enhancing DOX cytotoxicity and that DOX release was significantly enhanced upon exposure to AMF in athermic conditions. In addition, PlasMagNanoGels can efficiently generate heat by photothermy for thermotherapy. Therefore, the intrinsic properties of NPMs for magnetic targeting and as contrast agents for Magnetic Resonance Imaging (MRI), make these nanogels ideal candidates for a new therapeutic approach (diagnosis and treatment) against cancer
Jun, Chang-Lim. "Synthèse et caractérisation d'oligomères bifonctionnels racémiques et optiquement actifs dérivés de l'oxyde de propylène." Paris 6, 1986. http://www.theses.fr/1986PA066162.
Pellet, Alain. "Réactivité des pyridylacétonitrile, aminonitrile et éther de cyanhydrine vis à vis de composés carbonylés α, β [alpha-béta] éthyléniques : synthèse et stéréochimie de γ [gamma] cétonitriles et de γ [gamma] cétoaldéhydes." Paris 11, 1988. http://www.theses.fr/1988PA112130.
This work deals with the regioselectivity of addition of alpha nitrile carbanions on unsaturated carbonyl compounds in the aim of synthesizing gamma functionalized carbonyl compounds. In the first chapter, we have shawn that the addiion of lithiated 3-pyridylacetonitrile to various enones in tetrahydrofurane, followed by protonation, leads exclusively to 1,4 adducts, the bicylcic ketones are Cis ring fused. The cis or trans stereochemistry of the 2,3-disubstituted cyclanones depends on the protonation of enolates under kinetic or thermodynamic control. The 1,2 addition of this anion on 3-methyl 2-butene 1-al is performed in tetrahydrofurane whereas 1,4 addition is observed under thermodynamic control in the presence of hexamethylphosphoramide or trifluoroboron etherate. In the second chapter, we have realized regioselective additions of lithiated and potassiated dimethylaminophenylacetonitrile and lithiated (ethoxy-ethoxy) phenylacetonitrile (latent benzoyl equivalents) on various unsaturated aldehydes. Our study centers on the influence of the nature of the reactants, solvents, cations, Lewis acids, and experimental conditions on the regio and stereoselectivities of these additions. A methodology leading to ketoaldehydes and keto allylic alcohols, usually difficult to obtain, was improved and applied to the synthesis of optically active compounds. In the third chapter, the reductive decyanation by different borohydrides was studied on an aminonitrile model with the aim of accessing to aminoaldehydes and aminoallylic alcohols. The desired free amine is accompanied by various amounts of stable amine-borane complexe according to the reducing agent. This methodology, applied to 1,4 adducts, leads to the corresponding aminoalcohols while retrocondensation occurs from the1,2 adducts
Hennequin, Laurent. "Nouvelle méthode de préparation de composés dicarbonylés-1,5 : application à la synthèse de substances naturelles." Rouen, 1986. http://www.theses.fr/1986ROUES026.
Duflos, Jack. "Synthèse et réactions de cycloadditions sur des systèmes pyrroliques à noyaux condensés." Rouen, 1987. http://www.theses.fr/1987ROUES003.
Colin, Jean-Luc. "Synthèse et étude d'hétérocycles à activité biologique potentielle : Dérivés d'éthers halométhyliques aromatiques et prodrogues de l'acide oxolinique." Nancy 1, 1987. http://www.theses.fr/1987NAN10157.
Diaf, Ilhem. "Développement de nouveaux processus de cyclisation de dérivés alléniques catalysés par des triflates métalliques et synthèse de molécules odorantes." Thesis, Nice, 2014. http://www.theses.fr/2014NICE4124.
Novel processes of metal triflate-catalyzed cyclizations of functionalized allenes are presented. Two strategies have been developed. In a first part, the intramolecular carbonyl-ene reaction with γ-allenic ketones is described. This reaction proceeds under very mild conditions using only 1 mol% of bismuth(III) triflate. The scope of this reaction was extended to several γ-allenic ketone derivatives, featuring various substitution patterns. The resulting dienols were successfully engaged in a Diels-Alder reaction allowing the formation of polycyclic functionalized frameworks in good yields with excellent regio- and diastereoselectivities. In a second part, the metal triflate-catalyzed cyclization of allenic-enol ethers is described. This reaction gives access to cyclopentene derivatives in good yields using only 0.1 mol% of bismuth(III) triflate. Dihydrofuran derivatives could also be formed using this strategy. This cycloisomerisation reaction proceeds through an initial enol ether activation, followed by the nucleophilic attack of the allene moiety. This reactivity could be inverted using a gold(I) catalyst, in the presence of an exogenous nucleophile, allowing the formation of different products. Within our interest in flavor and fragrance chemistry, allenic acetates and alcohols have been synthesized and subjected to olfactive evaluation, revealing dominant fruity and floral notes. Green and woody undertones have been detected as well
Gaonac'h, Odile. "Accès rapide à des systèmes 1,3-diéniques 1-thiosubstitués, 4-fonctionnalisés." Rouen, 1992. http://www.theses.fr/1992ROUES038.
Joly, Jean-Pierre. "Synthèse d'éthers-couronnes osidiques et leur fixation sur support chromatographique en vue de la séparation d'énantiomères." Nancy 1, 1989. http://www.theses.fr/1989NAN10019.
Martin, Céline. "Réactions de delta-élimination : applications à la synthèse de diènes polyfonctionnels et de systèmes polycycliques analogues d'inhibiteurs de farnésyltransférase." Rouen, 1999. http://www.theses.fr/1999ROUES095.
Guigné, Claire de. "Réactions d'éthers de diénol pour l'accès à des structures terpéniques : condensation carbocationique et métallation vinylique." Rouen, 1997. http://www.theses.fr/1997ROUES034.
George, Nicolas. "Étude de la synthèse totale de tétrahydroisoquinoléines naturelles : quinocarcine, Tétrazomine et Lémonomycine. : rapide accés aux α-amidosulfures et leur utilisation en tant que précurseurs de N-acylimines dans la réaction de Friedel-Crafts." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00980348.
Valiquette, Dominic. "Électrofilage de fibres à partir de mélanges polystyrène/poly(vinyl méthyl éther)." Thèse, 2009. http://hdl.handle.net/1866/3607.
Electrospinning is a simple method for the preparation of polymer fibers with diameters of hundreds of nanometers to a few micrometers. Although it is a versatile method, some issues remain in the control of the structure and properties of electrospun fibers. In this study, fibers electrospun from polystyrene (PS)/poly(vinyl methyl ether) (PVME) blends were characterized. Differential scanning calorimetry (DSC) revealed that fibers electrospun from benzene are miscible while a phase separation occurs when the fibers are electrospun from chloroform. While films cast from chloroform show poor mechanical properties, immiscible fibers are ductile. The effects of the blend composition and the solvent on the fiber diameter and morphology were observed by scanning electron microscopy (SEM) and optical microscopy. Afterwards, contact angle measurements were made to evaluate the hydrophobicity of the fibers which decreases as hydrophilic PVME is added to the blend; the values for the fibers were found to be 60° higher than their equivalent in films. PVME was selectively removed from the immiscible fibers by complete immersion into water. Infrared spectroscopy revealed that this process increases the PS content from 70 to 95% for immiscible fibers but only to 75% for miscible fibers. These results show that the PVME-rich phase is almost completely distributed on the fiber surface, which was confirmed by atomic force microscopy (AFM) and SEM. Finally, the electrospinning of PS/PVME blends from chloroform/benzene solutions was studied. The presence of chloroform, even as a residual amount, causes a phase separation just as it does in fibers electrospun from pure chloroform.
Godin, François. "Synthèse totale du méthyl ester de la zincophorine et étude DFT du transfert d’hydrogène diastéréosélectif impliquant des intermédiaires radicalaires vicinaux à un ester." Thèse, 2014. http://hdl.handle.net/1866/11190.
The focus of this thesis is the use of free radical chemistry for the introduction of stereogenic centres in propionate motifs and application of this methodology to the total synthesis of zincophorin methyl ester. This ionophore, with interesting biological properties, displays several synthetic challenges including an anti, anti, anti, anti polypropionate sequence and a trisubstituted trans tetrahydropyran. Recently, the renewed interest for polyether compounds as anticancer agents emphasizes the significance of versatile strategies to access these targets, as well as analogues thereof. Over the last few years, our research group has been interested in the synthesis of acyclic polypropionates via a substrate-based strategy relying on two key reactions. The first one consists of a Mukaiyama aldol reaction between an alpha-chiral aldehyde and a tetrasubstituted enoxysilane bearing a carbon-halogen bond, where the stereochemical outcome depends on the monodentate or bidentate nature of the Lewis acid. The second key step involves the generation of a tertiary free radical, vicinal to an ester, which can be reduced diastereoselectively in presence of trialkyl tin hydride. The first section illustrates the elaboration of trisubstituted tetrahydropyran motifs and the induction of vicinal stereogenic centres via a radical reduction. We discovered that the diastereoselective outcome of the iodoetherification cyclization reaction was dictated by the gamma-methyl group of alpha,beta-unsaturated esters. Moreover, we showed that both anti and syn reduction products could be accessed from a common radical intermediate, respectively by relying on the exocyclic or endocyclic effect during the reduction reaction. Using a complementary strategy, we also revealed that the radical precursor could be accessed via a cycloetherification reaction in presence of a tetrasubstituted enoxysilane. A systematic investigation of the substituents on the ring indicated that certain stereochemical relationships led to a decrease in anti-selectivity. The second section presents a DFT study, at the BHandHLYP/TZVP level of theory, of radical intermediates involved in hydrogen transfer. Using an energy decomposition analysis, we were able to rationalize the diastereoselective outcome of the reaction on the basis of the distortion energy (∆Ed‡) and interaction energy (∆Eint‡) required to access pro anti and pro syn transition states. Moreover, we have demonstrated that a Natural Bond Orbital (NBO) analysis can be used to interpret stereoelectronic interactions. Subsequently, an evaluation of radical intermediates bearing a borinate or an aluminate revealed that steric hindrance of the propionate chain was mainly responsible for the selective formation of anti and syn reduction products in the presence of a Lewis acid. The last section describes the elaboration of the polypropionate sequence of zincophorin, and analogues thereof, from the substituted tetrahydropyran fragment. In our analysis, we have highlighted the necessity to limit the number of potential chelation sites to three during the aldol step under Cram-chelate conditions. Moreover, we demonstrated that the different aldol acetate motifs are accessible using a bulky enoxysilane. Finally, we showed that a similar reaction sequence can be used to access the C17–C25 fragment of its natural analogue CP-78,545 and have completed the most recent total synthesis of zincophorin methyl ester.
Wang, Xiaotian. "Studies toward the total synthesis of natural and unnatural aeruginosins." Thèse, 2009. http://hdl.handle.net/1866/3265.
We have demonstrated the usefulness of tert-butylsulfonyl (N-Bus) protecting group in amino acid and peptide chemistry. It is formed in a 2-step procedure involving reaction of an amine with tert-butylsulfinyl chloride, followed by oxidation with m-CPBA to obtain the corresponding tert-butyl- sulfonamides in excellent yields. The N-Bus group can be cleaved to regenerate the corresponding amino salt in 0.1 N TfOH/DCM/anisole at 0 oC for 10 h. A variety of N-Bus protected amino acids and other common amino acids can be used to form dipeptides and tripeptides. With the exception of the N-Fmoc group, the conditions required for the N-Bus group cleavage also cleaved the N-Boc, N-Cbz and O-Bn groups. Selective and orthogonal deprotection of N-Boc, N-Cbz, N-Fmoc and O-Bn groups could be achieved in the presence of the N-Bus protecting group. The new unnatural amino acids (3R, 2R) 3–methyl-D-leucine (β-Me-Leu) and its 2-methyl regioisomer were synthesized by ring opening of an N-Ts aziridine intermediate with excess LiMe2Cu. The 1:1.2 mixture of regioisomers were each converted to the corresponding methyl leucines, then coupled to D-phenyllactic acid, followed by coupling with 2-carboxyperhydroindole 4-amidino-benzamide core in the presence of DEPBT. Further elaboration led to linear peptidic unnatural analogues of known aeruginosins such as chlorodysinosin A. The two analogues were also evaluated in enzymatic assays for their inhibitory activity against thrombin and trypsin. The presumed 3-sulfated aeruginosin 205B and its β–anomer were successfully synthesized from 5 subunits: 3-chloroleucine, D-phenyllactic acid, D-xylose, 2-carboxy-6-hydroxyoctahydroindole, and agmatine. Comparison of 1H and 13C NMR reported data with that of synthetic aeruginosin 205B revealed a disturbing discrepancy with regard to the position of the presumed 3'-sulfate on the D-xylopyranosyl unit. We synthesized methyl α-D-xylopyranosides with sulfates at each of the hydroxyl groups and conclusively demonstrated the the presence of a C-4'-sulfate by comparison of the 1H and 13C NMR spectroscopic data. Thus, the structure of aeruginosin 205B should be revised. One of the key steps in the synthesis is glycoside formation of the axially oriented C-6 hydroxyl group in the Choi subunit. The 2-thiopyridyl carbonate was a suitable method for anomeric activation, followed by treatment with AgOTf and tetramethylurea in ether-DCM solution to give the desired α-anomer, which was easily separable from the β-anomer by column chromatography.