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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

Feste Katalysatoren für die Heck-Reaktion

Schell, Friedrich Alexander. January 1900 (has links) (PDF)
Stuttgart, Univ., Diss., 2003. / Computerdatei im Fernzugriff.
2

Ein neues phosphinfreies Katalysatorsystem für die HECK-Reaktion

Westermann, Elke. January 1999 (has links) (PDF)
Bochum, Universiẗat, Diss., 1999.
3

Feste Katalysatoren für die Heck-Reaktion

Schell, Friedrich Alexander. January 1900 (has links) (PDF)
Stuttgart, Universiẗat, Diss., 2003.
4

Studies towards the total synthesis of galanthamine and the total synthesis of 2-Benzoyl-9-azabicyclo[4.2.1]non-2-ene : phenyl analogue of (#+-#)Anatoxin-a

Sumoreeah, Ravi Leckman January 2002 (has links)
This thesisd escribess yntheticw ork carriedo ut on two separatep rojects. (i) Synthetics tudiest owardst he total synthesiso f galanthamine (ii) The total synthesis of 2-Benzoyl-9-azabicyclo[4.2.1 ]non-2-ene Galanthamine is an amaryllidaceae alkaloid processing a rigid tetracyclic structure with a fused dihydrobenzofuran onto a cyclohexenol and a bridging tertiary amine. 2-Benzoyl-9-azabicyclo[4.2.1]non-2-ene is an analogue of anatoxin-a, whereby the acetyl side chain has been substituted with a benzoyl group. Anatoxin-a itself possesses a 9-azabicyclo[4.2.1]nonane framework. Although structurally very different they both share a common feature in that they interact with acetylcholine receptors. Hence chapter 1 is an introduction to Alzheimer's disease which is primarily caused by a lack of acetylcholine. A literature review of the total syntheses of galanthamine and a background of galanthamine is described in chapter 2, whilst chapter 3 details the forward synthesis to the galanthamine framework but with a cyclopentenyl instead of a cyclohexenyl moiety and subsequent attempts for the elaboration of the cyclopentenyl into its corresponding cyclohexenyl moiety. Chapter 4 and 5 describes the published total syntheses of anatoxin-a and analogues of anatoxin-a, whilst chapter 6 concludes the total synthesis of the phenyl analogue of anatoxin-a via a key selenium mediated transannular cyclisation of a Boc-(3-Lactam to furnish the 9-azabicyclo[4.2. l]nonane ring system.
5

Bulky arylphosphines and arylarsines for catalysis of C-C bond-forming reactions

Wilkinson, Matthew January 2003 (has links)
No description available.
6

Ruthenium and palladium catalysed cyclisation reactions

Gleasure, A. J. January 2002 (has links)
No description available.
7

Synthesis of Mesoporous Palladium Nanoparticles and Its Application in Heck Reaction

Li, Jheng-Guang 20 January 2009 (has links)
In our study, 3D interconnection channels of mesoporous silica MCM-48 was used as template. We try to fill the channels with the metal precussor by ¡§incipient wetness¡¨ technique. After the reduction with H2, the composites containning metal Pd and MCM-48 could be obtained. Then, Pd nanowire network was obtained through HF etching. The mesoporous palladium nanoparticles are obtained and we try to use it as the catalyst in the Heck coupling reaction of £\-methylstyrene and p-bromoacetophenone. We find that our catalyst have different effect in this Heck reaction. The terminal and internal (E/Z form) isomer ratio variated in the reaction. In the future, we will attempt to apply our mesoporous Palladium nanoparticles as organic molecule storage. The MCM-48 and mesoporous Palladium nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution nitrogen adsorption.We used NMR and GC to trace the reaction. Heck reaction was performed as a test reaction to compare catalytic performances of the meosoporous Palladium nanoparticles and the catalyst of refrence.
8

Einsatzmöglichkeiten von 2,3-Dihydrofuran in der Polymerchemie

Braun, Harald. Unknown Date (has links)
Techn. Universiẗat, Diss., 2002--München.
9

1,8-Diaminoanthracene und 4,5-Diaminoacridine als Liganden für Übergangsmetalle

Rosskamp, Evelyn. January 2003 (has links)
Düsseldorf, Universiẗat, Diss., 2003.
10

Classicité de formes modulaires surconvergentes sur une variété de Shimura / Classicality of overconvergent modular forms on Shimura variety

Bijakowski, Stéphane 12 December 2014 (has links)
Nous nous intéressons aux formes modulaires surconvergentes définies sur certaines variétés de Shimura, et prouvons des théorèmes de classicité en grand poids. Dans un premier temps, nous étudions les variétés ayant bonne réduction, associées à des groupes non ramifiés en p. Nous nous intéressons aux variétés de Shimura PEL de type (A) et (C), qui sont associées respectivement à des groupes unitaires et symplectiques. Pour démontrer un théorème de classicité, nous utilisons la méthode du prolongement analytique, qui a été développée par Buzzard et Kassaei dans le cas de la courbe modulaire. Nous généralisons ensuite ce résultat de classicité à des variétés en ne supposant plus que le groupe associé est non ramifié en p. Dans le cas des formes modulaires de Hilbert, nous construisons des modèles entiers des compactifications de la variété, et démontrons un principe de Koecher. Pour des variétés de Shimura plus générales, nous travaillons avec le modèle rationnel de la variété, et utilisons un plongement vers une variété de Siegel pour définir les structures entières. / We deal with overconvergent modular forms défined on some Shimura varieties, andprove classicality results in the case of big weight. First we study the case of varieties with good reduction, associated to unramified groups in p. We deal with Shimura varieties of PEL type (A) and (C), which are associated respectively to unitary and symplectic groups. To prove a classicality theorem, we use the analytic continuation method, which has been developed by Buzzard and Kassaei in the case of the modular curve. We then generalize this classicality result for varieties without assuming that the associated group is unramified in p. In the case of Hilbert modular forms, we construct integral models of compactifications of the variety, and prove a Koecher principle. For more general Shimura varieties, we work with the rationnal model of the variety, and use an embedding to a Siegel variety to define the integral structures.

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