Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
Browse
3 results
Search Results
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 Synthesis of Α,β-Unsaturated Ketones by Rhodium-Catalyzed Carbonylative Arylation of Internal Alkynes With Arylboronic Acids(Izmir Institute of Technology, 2009) Kuş, Melih; Artok, Levent; Kuş, Melih; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of Technologyα,β-Unsaturated ketones are important key reagents in organic synthesis. They are commonly synthesised through an aldol condensation reaction.Since Hayashi et al. reported the first Rh-catalyzed addition of aryl- and alkenylboronic acids to α,β-unsaturated ketones, the Rh-catalyzed addition of organoboron reagents to various unsaturated systems has become increasingly popular as a method of constructing C.C bonds. Organoboron reagents readily undergo transmetalation with Rh to form arylrhodium(I) species that are capable of inducing the nucleophilic arylation of various electrophilic sites (Sakai, et al. 1997, Hayashi and Yamasaki 2003). In this work, we have succesfully performed another example of the Rhcatalyzed reaction of arylboronic acids: a reaction of arylboronic acids with alkynes under a CO atmosphere to yield α,β-unsaturated ketones (Kuş, et al. 2008). As a consequence, the methodology established in this study proposes arelatively mild and simple way for the synthesis of α,β-unsaturated ketones.Master Thesis Rhodium Catalyzed Arylative Cyclization of Diynes With Arylboronic Acids(Izmir Institute of Technology, 2009) Ürer, Bağdagül; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyThis study reveals that exo-conjugated cyclic dienes can be synthesized by rhodium(I) catalyzed arylative cyclization of unsymmetric diyne molecules with arylboronic acids. Cyclic dienes are important reagents in organic chemistry because they easily undergo [4+2] cycloaddition reactions with dienophiles and also, they are useful intermediates in the synthesis of complex polycyclic compounds. To form carbon.carbon bonds, transition metal catalyzed arylative cyclization reactions of unsaturated reagents with arylboronic acids is a useful and efficient way in organic synthesis. For this purpose, rhodium catalyzed arylative cyclization of enyne type unsaturated reagents have been found significantly in literature. In this study, unsymmetric diyne type molecules were reacted with arylboronic acids in the presence of a rhodium complex under argon atmosphere. The reactions proceeded effectively in methanol as a solvent under very mild reaction conditions.