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Synthesis of aza-bicyclic compounds via palladium-catalyzed cascade cyclization reactionsLo, Kai-yip., 羅啟業. January 2012 (has links)
A palladium-catalyzed oxidative cascade cyclization reaction has been developed to prepare pyrrolizidine and indolizidine derivatives from simple aliphatic alkenyl amides 2.1ak in one step in moderate to good yields, using Pd(TFA)2 as the catalyst and molecular oxygen (1 atm) as a green oxidant. This cascade cyclization can also proceed for ring-containing unsaturated amides 2.1ln to afford azatricyclic systems.
Palladium(II)-catalyzed dehydrohalogenation cascade cyclization reactions have been developed to synthesize polycyclic pyrrolizidine derivatives from iodoalkenylanilides 4.1ai in satisfactory to excellent yields under mild conditions. This reaction produces two stereocenters in one step and only one single diastereomer was obtained in the cyclization of 4.1. The reaction is proposed to proceed through an organopalladium(IV) species, formed by oxidative addition after the aminopalladation. This organopalladium(IV) species then undergoes reductive elimination to give the cyclized product. This cyclization is a fast and efficient way to construct natural alkaloids that contain pyrrolizidine or indolizidine cores. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
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Oxidative palladium catalysis under aerobic condition: studies on monocyclization of {221}-Keto amides and tandem cyclization ofAlkenyl anilinesYip, Kai-tai., 葉啟泰. January 2005 (has links)
published_or_final_version / abstract / Chemistry / Doctoral / Doctor of Philosophy
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The palladium catalyzed multicomponent synthesis of imidazoles and imidazole-containing [pi]-conjugated polymers /Siamaki, Ali Reza, 1965- January 2008 (has links)
The primary goal of this study is to develop novel metal catalyzed multicomponent reaction methods to generate imidazoles and their derivatives. This is directed towards the assembly of poly-substituted imidazoles, imidazolones and imidazole-containing pi-conjugated polymers. These products are generated in one-pot from such basic components as imines, acid chlorides, carbon monoxide, and/or organostannanes, via the use of palladium catalysis. / In Chapter 2, the design of a new palladium catalyzed synthesis of highly substituted imidazoles from imines and acid chlorides is described. This reaction involves the palladium catalyzed generation of 1, 3-oxazolium-5-oxides (Munchnones); which are trapped with N-tosyl substituted imines via a 1, 3 dipolar cycloaddition reaction to form the final products. Overall, this provides a one step method to assemble imidazoles from imines and acid chlorides with excellent regiochemical control. The versatility of this process is demonstrated by the assembly of diversely substituted imidazoles, including those with aryl, alkyl, heterocyclic and vinyl substituents. / Chapter 3 describes a new, palladium catalyzed, five component coupling of imines, chloroformates, organotin reagents, carbon monoxide and ammonium acetate to form imidazolones. The key step in this process is the efficient formation of ketocarbamates via the carbonylative cross coupling type reaction of imines, chloroformates and organostannanes. These products can be easily converted into imidazolones via a cyclocondensation with ammonium acetate. / The synthesis of pi-conjugated imidazole-containing polymers is described in Chapter 4. This process is designed based upon our previous studies on palladium catalyzed multicomponent synthesis of imidazoles, developed in Chapter 2. It is shown that bifunctional monomers such as di-imines, di-acid chlorides and di-N-tosylimines can be coupled together to assemble pi-conjugated imidazole-containing oligomers and polymers utilizing this same palladium catalyzed reaction. This approach was used to create a novel library of conjugated imidazole polymers. By modifying the substituents on the polymer structures, the UV-vis absorbance and fluorescence excitation/emission spectra of these compounds are varied over a range of 150 nm. / In Chapter 5, the palladium catalyzed multicomponent polymerization is discussed in more detail. This includes the analysis of the end groups on the polymer backbone, as well as mechanistic studies into how the polymerization is terminated. These results suggest that the sulfinate anion liberated upon N-tosylimine cycloaddition may be non-innocent in this polymerization, and its presence could lead to termination of the growing polymer chain.
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De novo asymmetric synthesis of mannopeptimycin-E, novobiocin and methymycin analoguesGuppi, Sanjeeva Rao. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 219 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 212-219).
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Palladium-catalyzed syntheses of indoles, pyrroloindoles, quinolines a base-mediated formation of N-alkoxyindoles, and progress toward the first total synthesis of echinosulfone A /Banini, Serge R. January 2008 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xv, 275 p. : ill. Includes abstract. Includes bibliographical references (p. 107-113).
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The activity of silica immobilized palladium N-heterocyclic carbene complexes toward Mizoro-Heck reaction and their characterization/Özge Aksın;thesis advisor Levent Artok.Aksın, Özge. Artok, Levent January 2005 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2005. / Keywords: Palladium, Immobilization, Heck Reaction, Palladium-N-Heterocyclic Carbene, Carbon-Carbon Coupling. Includes bibliographical references (leaves. 89-104).
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Silica Supported N-Heterocyclic Carbenes:Active and Reusable Heterogeneous Catalysts for Mizoroki-Heck Reactions/Açıkel, Müge. Artok,Levent January 2004 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology,İzmir, 2004 / Includes bibliographical references (leaves. 118-134).
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Catalytic hydrogenation of alpha-methylstyrene in liquid phase in stirred reactorJohnson, Douglas Lewellyn, January 1956 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 184-188).
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Pd/C-catalyzed Suzuki cross- and self- couplings & the development of a lab-scale hydrogenation systemChen, Jeng-Shiou. January 2008 (has links)
Thesis (Ph. D.)--Rutgers University, 2008. / "Graduate Program in Chemical and Biochemical Engineering." Includes bibliographical references (p. 116-122).
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Development of new palladium-catalyzed arylation reactions.Lafrance, Marc. January 2008 (has links)
Thesis (Ph.D.)--University of Ottawa, 2008. / Includes bibliographies. Also available via the World Wide Web.
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