Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Palladium Catalyzed Cross Coupling Reactions of Alkenyl Epoxides and Organoboronic Acid Esters(Izmir Institute of Technology, 2018) Eren, Ahmet; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyIn organic chemistry, it is a useful method to form a new allylic compounds as a result of 1-3 substitution reactions of allylic compounds which have a good leaving group. These reactions usually require a metal catalyst but one of the most challenging aspects of these applications is the process regio and stereo selectivity for a wide variety of substrate types. Other compounds such as alkenyl epoxides are also useful for 1-3 substitution reactions. An advantage of using alkenyl oxirane compounds is that the oxirane ring is opened in the substitution step to form a hydroxyl group and resulted in the formation of allylic alcohols which are important intermediate product. Metal catalysed and regioselective reactions of terminal alkenyl epoxides with organoborons have been reported in the literature. However, there is no successful method for internal alkenyl oxiranes. Thus, in this study, 1-3 substitution reactions of alkenyl oxiranes were successfully applied, which yielded allylic alcohols with high regio- and stereoselectivity.Master Thesis Palladium-Catalyzed Stereo-Selective 1.2-Addition Reactions of ?,?-Epoxy Esters With Organoborons(Izmir Institute of Technology, 2018) Bilgi, Yasemin; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyTransition metal-catalyzed SN2-type addition reactions of allylic compounds having good leaving groups is a valuable reaction procedure in organic chemistry. Vinyl epoxides, as a derivative of allylic compounds, are suitable reagents for substitution reactions with their high reactivity due to the presence of an epoxide ring tensions and a conjugated C-C double bond attached to this ring. The occurrence of a substitution reaction of such reagents over the allylic position allows synthesis of homoallylated alcohols, one of the key building blocks in the synthesis of natural compounds. Organoborans are stable against moisture and air and environmentally friendly compounds and are thought by us to be suitable nucleophiles in these reactions. Within the context of this research, Pd-catalyzed stereo-selective SN2-addition type arylation reactions of γ,δ-epoxy-α,β-unsaturated esters with organoborons were investigated. The reaction mechanism proceeds through formation of π-allylpalladium complex with the help of Pd-AsPh3 combination. The method has enabled to formation of γ-Aryl-δ-hydroxy-α,β-unsaturated esters with high regio- and stereo- selectivity.Master Thesis Synthesis of Allyl Alcohols by Paladium-Catalyzed 1,3-Substitution Reactions of Alkenyl Epoxides With Organoborons(Izmir Institute of Technology, 2016) Kıbrıs, Erman; Kıbrıs, Erman; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of Technology1,3-Substitution reactions of allylic compounds having a good leaving group is a prominent method in Organic Chemistry for the synthesis of new allylic reagents with an exchanged functional group. These reactions usually require the use of metal catalysts and one of the most challenging aspects for these applications is the regio- and stereo-selectivity of the process for a wide range of substrate types. Other compounds such as vinyl epoxides are also acceptable for substitution reactions. An important advantage of using these reagents is that opening of the oxirane ring during the substitution process lead to the generation of a hydroxyl group and as a result affords allyl alcohols which are important intermediaries in organic syntheses. An example of regio-selective metal-catalyzed reactions of vinyl epoxides having a terminal alkenyl group with environmentally benign organoborons was reported in the literature. However, no such success could be achieved with vinyl epoxides with an internal alkenyl group. Therefore, within the context of this method internal vinyl epoxides were successfully subjected to 1,3-substitution reactions with organoborons which yielded arylated allyl alcohols in both a regio- and stereo-selective manner. The method is applicable under quite mild conditions where a palladium-AsPh3 combination is used to activate the process.