Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
Browse
5 results
Search Results
Master Thesis Synthesis of 1,5-Disubstituted 1,2,3-Triazole Modified Azacoumarins(01. Izmir Institute of Technology, 2022) Çağır, Ali; Çağır, Ali; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyCancer is a deadly disease that threatens human health and all life, and it is still a serious problem despite all scientific studies for more than half a century. Pharmacophores are a part of the structure of a drug (or drug candidate) responsible from the biological activity. This thesis is related with the synthesis of novel compounds having two well-known pharmacophore structures, 1,2,3-triazole and 1-azacoumarin. Both structures can be found in the structure of many biologically active molecules. Triazole modified coumarin derivatives are scarce in the literature. In this study, we aimed to improve the synthetic route toward the synthesis of 1- azacoumarin derivative modified by 1,2,3-triazole group at position 4-. Synthesis starts with the conversion of methyl 4-chloroanthranilate to the corresponding 4-OH azacoumarin. Then it is transferred into the 4-OTf group by simply addition of Tf group to OH under basic condition. After Sonogashira reaction and removal of TMS group 4- alkynyl-1-azacoumarin was produced. At this point, conversion of alkyne into 1,5- disubstituted 1,2,3-triazole was examined in the presence of Cp2Ni-Xantphos and RuCl(COD)Cp* catalytic systems but all of trials were failed probably due to the presence of ester group close to the reaction site. In further studies, design of the molecule will be reperformed and ester group will be moved over phenyl rings in order to test its biological activity over cancer cell lines.Master Thesis Iridium Catalyzed Boration of Dihydroisoquinoline Derivatives(Izmir Institute of Technology, 2022) Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyTransition metal catalyzed borylation reactions have an important place in organometallic chemistry. In recent years, these reactions have been extensively investigated and have become a versatile tool in the synthesis of new organic materials. C-H bonds can be easily transformed into C-B bonds by borylation reactions. In particular, iridium-catalyzed borylation includes significant advances such as mild reaction conditions, additive-free, high efficiency and being in a single step. In this thesis, the borylation of dihydroisoquinolines with a wide range of biological properties was performed for the first time. Investigating the extent of the reaction has led to the development of optimization studies. Besides, the effects of steric and electronic factors on selectivity are also shown. In this new methodology, C3-borylated products with high regioselectivity and yield were formed with the directing effect of the acyl group. The use of AsPh3 as a ligand is critical to the product selectivity of the method. When the reagent scope was investigated, it was determined that the functional group tolerance of the reactions was quite high. Finally, borylated dihydroisoquinolines have been converted into various intermediates by application studies.Master Thesis Synthesis of Simple 2'-alkoxymethyl Substituted Klavuzon Derivatives(Izmir Institute of Technology, 2017) Çetinkaya, Hakkı; Çağır, Ali; Çağır, Ali; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of Technologyα,β-Unsaturated δ-lactones are the members of lactones, which are cyclic esters. They are quite valuable compounds because of their Michael acceptor property at unsaturated carbonyl functional group. It is believed that soft nucleophilic parts of the enzymes react with the β-carbon of lactone and form a covalent bond. If that is occurred at the active site of an enzyme, its activity is inhibited irreversibly. (R)-goniothalamin is a α,β-unsaturated lactone and it was shown that it has a selective cytotoxic activity over cancer cells. It is less cytotoxic in healthy cells. Later, Kasaplar and coworkers synthesized the klavuzon derivatives, which can be considered as the close relatives of goniothalamins. In this study novel derivatives of simple 2’-alkoxymethyl substituted klavuzon derivatives were synthesized. For this purpose, we started with 2-methyl-1-naphtoic acid, which can be transferred to ethyl 2-methyl-1-naphtoate by reacting with iodoethane under basic condition. Next, formed ester reacted with Br2 molecules generated in situ by NaBrO3 and NaHSO3. Then formed ethyl 2-(bromomethyl)-1-naphtoate reacted with various alcohols under basic conditions to form ethyl-2-alkoxymethyl-1-naphtoate. These esters are coverted to the target klavuzon products in five steps that are reduction with LiAlH4, oxidation with PCC, addition of allylmagnesium bromide, acrylate ester formation and ring closing metathesis reactions.Master Thesis Coupling Reactions of Enyne Oxiranes With Grignard Reagents(Izmir Institute of Technology, 2016) Aytaç, İsmet Arınç; Artok, Levent; Artok, Levent; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyLaboratory-synthesized (Z)-2,4-Enyne oxiranes were subjected iron-catalyzed reactions with Grignard reagents. The reactions afforded majorly E-configured vinylallenes with a hydroxyl group on the allylic carbon as the 1,5-(SN2'')-substitution products. However, in some case, along with the desired vinyllallenes products, 1,1- (SN2) and 1,3-substitution (SN2’) by-products were also recovered. Diastereo-selectivity of the method is strictly reliant on the syn/anti mode of the alkylation process. This study provides a new methodology for the synthesis of vinylallenes which are potential building blocks of biological active molecules.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.