Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Palladium-Catalyzed Alkoxycarbonylation Reactions of (e)-2 Carbonates(Izmir Institute of Technology, 2013) Karagöz, Ezgi Şule; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyTransition metal-catalyzed carbon-carbon bond formation reactions are well-rounded methods to synthetic organic chemistry. One type of these reactions is the alkoxycarbonylation reactions performed in the presence of a transition metal catalyst, an alcohol and carbon monoxide atmosphere. Investigations on palladium-catalyzed alkoxycarbonylation reaction of allylic compounds leading to β,γ-unsaturated esters have been performed. Moreover propargyl derivatives are prominent reactants for palladium-catalyzed alkoxycarbonylation reactions to yield allene esters which proceed through a σ-allenylpalladium intermediate. Palladium-catalyzed alkoxycarbonylation reaction of some enantio-enriched propargylic derivatives that facilitate unique centre-to-axis chirality transfer is still inadequate and essential. In this study, the palladium-catalyzed alkoxycarbonylation reaction of E-configured 2,4-enyne carbonates which afforded exclusively ester functionalized (E)-configured vinylallenes through the formation of σ-vinylallenylpalladium species was performed. Moreover the chirality transfer of the proposed method was also surveyed over an enantio-enriched E-enyne carbonate.Master Thesis Palladium Catalyzed Reactions of 2-En Carbonates With Organoboronic Acids(Izmir Institute of Technology, 2011) Üçüncü, Muhammed; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyRecently, transition metal catalyzed carbon-carbon bond formation reactions gain numerous importance in organic chemistry. Especially, palladium catalyzed carbon-carbon bond formation reactions provide lots of advantages in organic synthesis. For instance, palladium catalyst is extensively used in many allene formation reactions of various substrates such as propargyl and enyne compounds. This thesis describes the preparation of E-configured aryl or alkenyl functionalized vinylallene structures via the reaction of a 2-en-4-yne carbonates with organoboronic acids in the presence of Pd (0) precursor. This method, which proceeds through formation of s-vinylallenylpalladium intermediate, is applicable for both (E)- and (Z)- configured enyne carbonates and appeared to have wider scope for both organoboronic acids and enyne substrates. The reaction of the carbonate of an enantiomerically enriched enynol reagent with phenylboronic acid under the optimal conditions was proceeded and center-to-axis chirality transfer selectivity was investigated. Complete racemization was observed.Master Thesis Palladium Catalyzed Alkoxycarbonylation Reactions of 2-En Carbonates(Izmir Institute of Technology, 2011) Akpınar, Gürkan Eray; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyHomogeneous catalysis relaying on transition metal complexes has led to innovation in organic chemistry. Palladium complexes are the most versatile and used extensively in organic synthesis. One type of these reactions is the carbonylation reactions with palladium complexes in the presence of alcohol and carbon monoxide. Extensive studies have been carried out on palladium-catalyzed carbonylation reactions of allylic and propargylic compounds. Alkynes containing a leaving group in propargylic position undergo alkoxycarbonylation reactions through the involvement of an σ-allenylpalladium as an intermediate to produce allenic esters. On the other hand, allylic compounds usually leads to β,γ-unsaturated esters through the involvement of a π- allylpalladium complex, when subjected to alkoxycarbonylation processes. With the high reactivity of allyl carbonates and propargyl carbonates in mind toward P(0)-catalyzed reactions, we attemped the palladium catalyzed alkoxycarbonylation reaction of Z- or E-configured 2,4-enyne carbonates leading to vinylallene ester structures. The reactions involved 1,5-type substitution and proceeded through formation of σ-vinylallenylpalladium species.