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Koushki, Behzad | 2013

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  1. Type of Document: Ph.D. Dissertation
  2. Language: Farsi
  3. Document No: 44988 (03)
  4. University: Sharif University of Technology
  5. Department: Chemistry
  6. Advisor(s): Matloubi Moghaddam, Firouz
  7. Abstract:
  8. We have reported a new and efficient synthesis of a broad spectrum of heterotetracyclic benzoxazocines via unique tandem 1,3-dinucleophilic addition of different bifunctional nucleophiles to quinolinium and isoquinolinium salts. The reaction generally involves the initial addition of nucleophiles to quinolinium salts to form enamine intermediate which can be trapped by intramolecular O/S-alkylation of nucleophiles. In the third part, as continues, we have reported another method which consists of Anthocyanidins and Thioindoles by using water and acetic acid as the solvent. This protocol is a very mild and simple method for construction of eight-membered ring in fused heterocycles in a one-step process. In the following, We have reported a new and efficient synthesis of tetrahydrothiopyrano [2,3-b]indole skeletons via unique tandem reaction of indoline-2-thiones to Baylis-Hillman adduct acetates. This protocol is a very mild and simple method for construction heterocycles in a one-step process. This is a convenient and diastereoselective synthesis of methyl 4-aryl-2,3,4,9-tetrahydrothiopyrano[2,3-b]indole-3-carboxylate systems in the presence of K2CO3 in acetonitrile. The major benefits of the current study are the one-pot procedure, high yields and diastereoselectivity, short reaction times and the similarity of the products to the biologically active moieties. We have also utilized 4-hydroxyquinolinones were applied as 1,3-dinucleophiles in the reaction with Baylis-Hillman adduct acetates to synthesizenovel 2H-pyrano[3,2-c]quinoline-2,5(6H)-diones which are present in a number of biologically active compounds. The reaction was carried out under different conditions to achieve the optimum ones. The results indicated that acetonitrile as solvent and K2CO3 as base, under reflux conditions, were the optimum conditions. The reaction times are short and the experimental procedure is straightforward.In the last chapter, Compound 3-benzyl-2H-pyrano [3,2-c]chromene-2,5(6H)-dione (3), was prepared and fully characterized. The vibrational modes (FTIR) and NMR data (1H and 13C chemical shifts) were compared with the results of Density Functional Theory (DFT) method at the B3LYP/cc-PVTZ level. The calculated vibrational frequencies and NMR chemical shifts are in good agreement with the experimental results. The electronic (UV-Vis) spectrum was calculated using the TD-DFT method in CH2Cl2 with the Polarizable Continuum Model using the integral equation formalism variant (IEFPCM) and was correlated to the experimental spectra. The assignment and analysis of the frontier HOMO and LUMO orbitals indicate that absorption band is originated mainly from the π→π* transitions.
  9. Keywords:
  10. Tandem Reaction ; Quinolinium Salt ; Thio-Oxindole ; Computational Method ; Dinucleophile ; Flavylium Perchlorate Salts ; Anthocyanidin ; Heterocylic Compounds

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