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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Group 9 metal catalysts for the homogeneous hydrogenation of carbon-nitrogen double bonds

Bedford, Robin Bruce January 1994 (has links)
No description available.
2

Synthesis Of Ferrocenyl Substituted Quinolines

Velioglu, Ozlem 01 August 2008 (has links) (PDF)
Quinolines have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The incorporation of the essential structural features of quinolines with a ferrocene moiety could provide new derivatives with unexpected and/or enhanced biological activities since several ferrocene derivatives have already been shown to be active against a number of tumors. For this reason, we investigated the synthesis of ferrocenyl-substituted quinolines, such as 2-ferrocenylquinoline, by employing the molecular iodine catalyzed reaction between enolizable aldehydes and ferrocenyl imines, which were prepared by the condensation reactions of ferrocenecarboxaldehyde with aniline derivatives. As anticipated, these reactions produced 2-ferrocenylquinoline derivatives. By employing this ethodology, we synthesized 2-ferrocenylquinoline, 6-chloro-2-ferrocenylquinoline, 6-bromo-2-ferrocenyl-quinoline, 2-ferrocenyl-7-methylquinoline and 2-ferrocenyl-3,7-dimethylquinoline. Due to the ready availability of ferrocenylimines and aldehydes, this practical onepot method represents a versatile synthesis of ferrocenyl-substituted quinolines.
3

Synthesis Of Ferrocenyl Quinones And Polyquinanes

Eralp, Tugce 01 June 2005 (has links) (PDF)
ABSTRACT SYNTHESIS OF FERROCENYL QUINONES AND POLYQUINANES Eralp, Tug&ccedil / e M.S., Department of Chemistry Supervisor: Assoc. Prof. Dr. Metin Zora June 2005, 79 pages With the discovery of antitumor activity of ferrocene derivatives, research on new ferrocene derivatives have gained importance. For this purpose, we have investigated the synthesis of ferrocenyl quinones starting from squaric acid. Several quinone derivatives are known to have antitumor and antibiotic activities. In this research, by combining ferrocene and quinone moieties, we have targeted ferrocenyl quinones which are supposed to have enhanced potential antitumor activity. Thermolysis of ferrocenyl-substituted 4-alkynyl cyclobutenones, which have been prepared from ferrocenyl cyclobutenediones and alkynyllithiums, leads to the formation of ferrocenyl quinones and besides also cyclopentendiones are observed. Ferrocenyl cyclobutenediones have been prepared from known cyclobutenediones by nucleophilic addition of ferrocenyllithium followed by hydrolysis. A mechanism for the formation of ferrocenyl substituted quinones, involving first electrocyclic ring opening of alkynyl substituted cyclobutenone to ketene intermediate and then ring closure, has been proposed. Polyquinanes are widely found in nature and proved to have biological activity such as antibiotic activity. For the synthesis of ferrocenyl polyquinanes, starting from squaric acid, ferrocenyl substituted cyclobutenediones were prepared and reacted with alkenyllithium, and hydrolyzed to afford ferrocenyl substituted polyquinanes. A mechanism has been proposed that involves first the formation of cis- and trans-divinyl substituted cyclobutenes that produce cyclooctatriene-dienolate, upon hydrolysis of this dienolate, aldol-type transannular ring closure reaction takes place, producing polyquinanes.
4

Synthèse et caractérisation de polymères à propriétés rédox pour un contrôle des propriétés d'adhésion bactérienne / Synthesis and characterization of redox polymers for a control of bacterial adhesion properties

Nguema Edzang, Ronald W 27 January 2016 (has links)
En raison des propriétés redox réversibles du ferrocène et de son activité antibactérienne, les polymères à base de ferrocène sont intéressants pour synthétiser de nouveaux liants pour des revêtements anti-adhésifs bactériens. Cette étude rend compte de l’homopolymérisation et de la copolymérisation de monomères méthacryliques porteurs de groupes ferrocényles avec le méthacrylate de lauryle (LM). Le méthacrylate de méthylferrocène (FMMA) mais aussi quatre nouveaux monomères nommés méthacrylate de 2- ferrocénylméthoxyéthyle (FMOEMA), méthacrylate de 3-ferrocénylméthoxypropyle (FMOPMA), 4- ferrocénylméthoxybutyle (FMOBMA) et de 2-ferrocénylméthoxyméthyléthyle (FMOMEMA) ont d’ bord été synthétisés et ensuite polymérisés via le procédé RAFT. Les cinétiques ’homopolymérisation ont été étudiées par RMN 1H in situ. La polymérisation a été contrôlée en utilisant le 2-cyanoprop-2-yl dithiobenzoate (CPDB) comme agent de transfert de chaîne, à 70°C, dans le toluène deutéré. Ces monomères contenant le groupement ferrocényle se sont révélés très réactifs via le procédé RAFT, conduisant à des conversions de 96% et à des polymères de faibles indices de polymolécularité (Ð<1,6). La conversion des monomères suit une cinétique de premier ordre (jusqu’à 80%) avec une augmentation linéaire de la masse molaire en fonction de la conversion en monomère. En utilisant le monomère FMMA comme référence, l’ spacement entre la partie polymérisable et le groupement ferrocényle a été augmenté pour le FMOEMA, FMOPMA, FMOMEMA et FMOBMA afin d’ méliorer la mobilité des groupements latéraux. Cette mobilité se traduit par une diminution notable des températures de transition vitreuse des homopolymères entre le pFMMA et le pFMOBMA. De plus, les copolymères diblocs préparés par voie séquencée présentent deux températures de transition vitreuse spécifiques à chaque bloc, démontrant une incompatibilité de ces derniers. Les propriétés électrochimiques des monomères et celles des polymères ont été caractérisées par voltampérométrie cyclique. Enfin, les propriétés anti-adhésives de ces homopolymères et copolymères diblocs vis-à-vis d’une bactérie marine ont été évaluées. / Due to the reversible redox properties of ferrocene and its antibacterial activity, ferrocenyl-based polymers are useful for the synthesis of new anti-adhesive binders for marine antifouling coatings. This study reports the homopolymerization and copolymerization with lauryl methacrylate of ferrocenyl-based methacrylic monomers. Ferrocenylmethyl methacrylate (FMMA) as well as four novel monomers, namely 2- (ferrocenylmethoxy)ethyl methacrylate (FMOEMA), 3-(ferrocenylmethoxy)propyl methacrylate (FMOPMA),4-(ferrocenylmethoxy)butyl methacrylate (FMOBMA) and 2-(ferrocenylmethoxy)methylethyl methacrylate (FMOMEMA) were first synthesized, and subsequently polymerized by the RAFT process. The homopolymerization kinetics were investigated by in situ NMR. The radical polymerization was controlled by using 2-cyanoprop-2-yl dithiobenzoate (CPDB) as a chain transfer agent, at 70 °C in deuterated toluene. These monomers containing a ferrocenyl moiety with alcoxy linkers were found to be as reactive as FMMA in RAFT polymerization, resulting in conversions of 96% and in polymers with low dispersities (ÐM < 1.6). Monomer conversion follows a first order kinetics (up to 80%) with a linear increase in the molecular mass as a function of the monomer conversion. By using the FMMA monomer as a reference, the length of the alcoxy linker between the ferrocene unit and the backbone was increased for FMOEMA, FMOPMA, FMOMEMA and FMOBMA to improve the mobility of the side groups. This increase in macromolecular mobility led to a significant decrease of glass transition temperatures of the homopolymers. In addition, diblock copolymers exhibited two glass transition temperatures indicating that the two blocks are incompatible. The electrochemical properties of the monomers and those of the polymers were characterized using cyclic voltammetry. Finally, the anti-adhesive properties of these homopolymers and diblock copolymers toward marine bacteria were evaluated.
5

Synthese von Ferrocenylphosphan- und Ferrocenyldiphosphan-basierenden Übergangsmetallkomplexen sowie deren Verwendung in der homogenen Katalyse

Schreiner, Claus 19 April 2010 (has links) (PDF)
Im Rahmen der vorliegenden Arbeit wurden Studien zur Modifizierung und Immobilisierung mono- und bidentater Ferrocenylphosphane an Carbosilan-Trägermolekülen durchgeführt. Erstere wurden in die entsprechenden (p-Cymen)RuCl2-Komplexe überführt und als (Prä)Katalysatoren für die Oxopropylester-Synthese eingesetzt. Dabei wurden sowohl der Einfluss unterschiedlicher Ferrocenylphosphan-Liganden als auch der Effekt der Immobilisierung auf die katalytische Umsetzung herausgearbeitet. Im Weiteren konnte eine neuartige Klasse funktionalisierter zweizähniger Diphosphane des dppf-Typs erschlossen und ihre Identität eindeutig belegt werden. Geeignete Vertreter dieser Verbindungsklasse wurden wie die entsprechenden monodentaten Ferrocenylphosphane an Carbosilan-Grundgerüste angebunden und, nach Überführung in die entsprechenden PdCl2-Komplexe, als (Prä)Katalysatoren für Heck-Kreuzkupplungsreaktionen verwendet. Auch hier konnte der Effekt der Immobilisierung sowie der Einfluss der unterschiedlichen Phosphanliganden auf die katalytische Reaktion ermittelt werden. Abschließend wurden Untersuchungen zur Verwendung monomerer Mesitylphosphan-substituierter Ferrocenyldiphosphane als Liganden in der Heck-Reaktion unterschiedlicher Arylhalogenide mit Acrylaten zu den entsprechenden Zimtsäureestern durchgeführt. Zur Bestimmung der katalytischen Leistungsfähigkeit wurde neben Reaktionstemperaturen und Katalysatorkonzentrationen insbesondere die verwendete Halogenkomponente variiert.
6

Synthesis Of Ferrocenyl Cycloheptadienones

Acikgoz, Canet 01 August 2005 (has links) (PDF)
SYNTHESIS OF FERROCENYL CYCLOHEPTADIENONES A&ccedil / ikg&ouml / z, Canet M.S., Department of Chemistry Supervisor: Assoc. Prof. Dr. Metin Zora August 2005, 85 pages Synthesis of seven-membered ring systems such as cycloheptadienones has attracted a great deal of attention in organic chemistry since they are present in a variety of biologically important molecules. Incorporation of the essential structures of such compounds with a ferrocene moiety instead of an aryl group could provide subtances with enhanced antitumor activities since some ferrocene derivatives have already proved to be active against a number of tumors. To develop a ferrocenyl-substituted seven-membered ring forming reaction, we have investigated the reaction of cyclopropylcarbene-molybdenum complex with ferrocenyl-substituted alkynes. As ferrocenyl-substituted alkyne, ferrocenyl&not / propyne (25B), (2-ferrocenylethynyl)trimethylsilane (25C), 1-ferrocenyl-3-phenylprop-1-yne (25D), 1-ferrocenyl-2-phenylethyne (25E), diferrocenylethyne (25F), ferrocenyl(formyl)acetylene (25G) were synthesized starting from ethynylferrocene (25A). The reaction between cyclopropylcarbene-molybdenum complex and ferrocenyl alkynes produced ferrocenyl-substituted cycloheptadienones 26, hydrolysis product of cycloheptadienones, 27, &amp / #61537 / -hydroxycycloheptadienones 28 and cyclobutenones 29, depending on the substitution pattern of the alkyne moiety. Interestingly, &amp / #61537 / -hydroxycycloheptadienone product 28B was isolated from these types of reactions for the first time. Terminal alkynes, trimethyl- and formyl-substituted alkynes did not produce any expected product, possibly depending on the steric and electronic effects, and/or the polymerization of the alkyne. Proposed mechanism for the formation of cycloheptadienones involves metallacyclobutene formation, electrocyclic ring opening, electrocyclic ring closure, CO insertion, reductive elimination.
7

Synthese von Ferrocenylphosphan- und Ferrocenyldiphosphan-basierenden Übergangsmetallkomplexen sowie deren Verwendung in der homogenen Katalyse

Schreiner, Claus 29 January 2010 (has links)
Im Rahmen der vorliegenden Arbeit wurden Studien zur Modifizierung und Immobilisierung mono- und bidentater Ferrocenylphosphane an Carbosilan-Trägermolekülen durchgeführt. Erstere wurden in die entsprechenden (p-Cymen)RuCl2-Komplexe überführt und als (Prä)Katalysatoren für die Oxopropylester-Synthese eingesetzt. Dabei wurden sowohl der Einfluss unterschiedlicher Ferrocenylphosphan-Liganden als auch der Effekt der Immobilisierung auf die katalytische Umsetzung herausgearbeitet. Im Weiteren konnte eine neuartige Klasse funktionalisierter zweizähniger Diphosphane des dppf-Typs erschlossen und ihre Identität eindeutig belegt werden. Geeignete Vertreter dieser Verbindungsklasse wurden wie die entsprechenden monodentaten Ferrocenylphosphane an Carbosilan-Grundgerüste angebunden und, nach Überführung in die entsprechenden PdCl2-Komplexe, als (Prä)Katalysatoren für Heck-Kreuzkupplungsreaktionen verwendet. Auch hier konnte der Effekt der Immobilisierung sowie der Einfluss der unterschiedlichen Phosphanliganden auf die katalytische Reaktion ermittelt werden. Abschließend wurden Untersuchungen zur Verwendung monomerer Mesitylphosphan-substituierter Ferrocenyldiphosphane als Liganden in der Heck-Reaktion unterschiedlicher Arylhalogenide mit Acrylaten zu den entsprechenden Zimtsäureestern durchgeführt. Zur Bestimmung der katalytischen Leistungsfähigkeit wurde neben Reaktionstemperaturen und Katalysatorkonzentrationen insbesondere die verwendete Halogenkomponente variiert.
8

Nouvelle méthode pour des réactions de cycloaddition/désaromatisation stéreocontrolées sous conditions catalytiques / Novel methods for stereocontrolled cycloaddition/dearomatization reactions under catalytic conditions

Lacambra, Aitor 28 April 2017 (has links)
Les alcaloïdes sont, en général, une famille de composés hétérocycliquesd'origine végétale qui intègrent des atomes d'azote dans leur structure complexe.Leur intérêt réside dans les activités biologiques intéressantes qu'ils présentent, etpour cette raison, ils sont largement utilisés par l'industrie pharmaceutique. Enparticulier, les anneaux de pyrrolidine et de pipéridine se trouvent comme basefondamentale dans un grand nombre de telles structures. D'autre part, l'un desprincipaux objectifs de la chimie synthétique est d'obtenir ces types de moléculesd'une manière asymétrique. Entre autres, la catalyse métallique s'est révélée trèsutile à cet effet. Par exemple, les ligands de type ferrocényle précédemmentdéveloppés dans notre groupe donnent naissance à des pyrrolidines énantiopuréesdensément substituées. De même, ces types de ligands ont été évalués dansdifférents types de réactions de cycloaddition, ce qui a entraîné la formationasymétrique de structures tricycliques d'intérêt biologique. D'autre part, une synthèseracémique collective de composés tétracycliques de la famille Securinega a étédéveloppée. Cette synthèse permet d'accéder à différents produits naturels de lafamille en raison de la polyvalence de l'intermédiaire lactone bicyclique. / Alkaloids are, in general, a family of heterocyclic compounds of vegetal originthat incorporate nitrogen atoms in their complex structure. Their interest lies in theoutstanding biological activities they present, and for this reason they are widely usedby the pharmaceutical industry. In particular, pyrrolidine and piperidine rings arefundamental scaffolds found in a large number of such structures. On the other hand,one of the main objectives of synthetic chemistry is to obtain these types ofmolecules in an asymmetric way. Among others, metal catalysis has proven to bevery useful for this purpose. For example, ferrocenyl proline ligands previouslydeveloped in our group gave rise to densely substituted enantiopure pyrrolidines.Likewise, these types of ligands have been evaluated in different types ofcycloaddition reactions, which have resulted in the asymmetric formation of tricyclicstructures of biological interest. In contrast, a collective racemic synthesis oftetracyclic compounds of the Securinega family has been developed. This synthesisprovides an access to different natural products of the family due to the divergencegiven by a bicyclic lactone intermediate.
9

Synthesis Of Ferrocenyl Quinones And Ferrocenyl Based Burning Rate Catalysts

Acikalin, Serdar 01 January 2003 (has links) (PDF)
Recently, considerable interest has been devoted to the synthesis of new ferrocene derivatives since properly functionalized ferrocene derivatives could be potential antitumor substances. For this purpose, we have investigated the synthesis of ferrocenyl quinones starting from squaric acid. Thermolysis of ferrocenylsubstituted cyclobutenones, which have been prepared from ferrocenyl cyclobutenediones and alkenyllithiums, affords hydroquinones, which furnish, upon oxidation, ferrocenyl quinones. Ferrocenyl cyclobutenediones have been prepared from known cyclobutenediones by nucleophilic addition of ferrocenyllithiumfollowed by hydrolysis, Pd/Cu-cocatalyzed cross-coupling with (tri-n-butylstannyl)ferrocene or Friedel&amp / #8211 / Crafts alkylation with ferrocene. A mechanism involving electrocyclic ring opening of alkenyl substituted cyclobutenone to dienylketene and consequent electrocyclic ring closure to cyclohexadienone followed by enolization has been proposed to account for the formation of ferocenyl substituted hydroquinones. Rocket design and production is one of the hottest topics in defense industry. On this subject, significant amount of investments have been done and excellent results were obtained. Among the burning rate catalysts for composite rocket propellants, ferrocene derivatives are one of the most famous ones. Although ferrocene derivatives are superior to some other burning rate catalysts, their use has some drawbacks arising from the tendency of migration in the bulk of the material and their sensitivity toward oxidation by air. With the aim of preventing the negative aspects of ferrocene derivatives, we have investigated the synthesis of EDA (ethylenediamine), TEP (tetraethylenepentamine) and DDI (dimeryl-diisocyanate) based ferrocene derivatives.
10

Tetracarbonyl[n,n

Akyol, Ceyhun 01 March 2005 (has links) (PDF)
N,N&rsquo / -bis(ferrocenylmethylene)ethylenediamine was prepared from the reaction of ferrocenecarboxaldehyde and ethylenediamine and characterized by IR, Raman, 1H and 13C-NMR spectroscopy. The electrochemical behaviour of this ligand was also studied for the first time by cyclic voltammetry. Diferrocenyl diimine ligand was used in the thermal substitution of 1,5-cyclooctadiene in Cr(CO)4(2:2-1,5-cyclooctadiene) at 38&deg / C in toluene for two hours to form the tetracarbonyl[N,N&rsquo / -bis(ferrocenylmethylene)ethylenediamine]chromium(0), [Cr(CO)4(BFEDA)]. This complex was succesfully isolated and crystallized from its 1:1 toluene/dichloromethane solution and characterized by elemental analysis, MS, IR, 1H, 13C-NMR spectroscopy. Electrochemical behaviour of the complex was also studied by cyclic voltammetry and the mechanism of electrode reaction was investigated by in-situ UV-VIS and IR spectroscopy measurements. This new complex has the iron atom of ferrocene unit in conjugation with the chromium metal center and, therefore, shows an electronic communication between two metal atoms.

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