WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

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  • Article
    Effect of Marination on the Formation of Polycyclic Aromatic Hydrocarbons in Grilled Vegetables
    (Wiley, 2025) Kacmaz Ozcetin, Sibel; Artok, Levent
    The effect of marination on the formation of polycyclic aromatic hydrocarbons (PAH) in charcoal-grilled vegetables was studied. Various marinade ingredients, including apple cider vinegar, red grape vinegar, lemon juice, garlic powder, black pepper, and the food additive tert-butylhydroquinone (TBHQ) were applied to vegetable samples before charcoal grilling. The total phenolic content (TPC) and total antioxidant capacity (TAC) of each marinade ingredient were assessed for their contribution to PAH inhibition. A substantial decrease in PAH4 formation was observed in marinated vegetables. Red grape vinegar exhibited the strongest average inhibitory effect on total PAH4 formation (75%), followed by apple vinegar (68%), lemon juice (52%), garlic powder (34%), and black pepper (30%). Additionally, the TBHQ (67%) demonstrated a strong inhibitory effect, reducing total PAH4 formation by 67%. These findings offer valuable insights for reducing PAH levels in grilled vegetables and preventing their formation.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Palladium-Catalysed Reactions of Conjugated Enyne Oxiranes With Organoborons: a Diastereoselective Method of the Synthesis of 2,4,5-Trienol Derivatives
    (Elsevier, 2017) Ziyanak, Fırat; Kuş, Melih; Alkan Karadeniz, Leman; Artok, Levent
    A palladium-catalysed reaction of conjugated enyne oxiranes with organoboron reagents is described. This method allows aryl-substituted vinylallenes containing a hydroxyl group on the allylic position to be synthesized, with good diastereomeric ratios, under mild conditions.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Palladium-Catalyzed Coupling of 2-En Carbonates With Terminal Alkynes
    (Elsevier Ltd., 2018) Taç, Doğan; Artok, Levent
    The first palladium-catalysed coupling of the carbonates of (E)-configured conjugated enynols with terminal alkynes is described. This method allows the synthesis of vinyl-allenynes with good yields. It has been determined that the method is not suitable for the (Z)-configured substrates.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 14
    Rhodium(i)-Catalyzed Carbonylative Arylation of Alkynes With Arylboronic Acids Using Formaldehyde as a Carbonyl Source
    (Georg Thieme Verlag, 2014) Wang, Chuang; Morimoto, Tsumoru; Kanashiro, Hiroyuki; Tanimoto, Hiroki; Nishiyama, Yasuhiro; Kakiuchi, Kiyomi; Artok, Levent
    The rhodium(I)-catalyzed reaction of alkynes with arylboronic acids in the presence of formaldehyde resulted in a carbon monoxide gas-free carbonylative arylation to yield α,β-enones. The simultaneous loading of phosphine-ligated and phosphine-free rhodium(I) complexes is required for efficient catalysis, which catalyze the abstraction of a carbonyl moiety from formaldehyde (decarbonylation) and its subsequent introduction into the substrate (carbonylation), respectively.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 10
    Iron-Promoted 1,5-Substitution (sn2' Reactions of Enyne Acetates and Oxiranes With Grignard Reagents
    (Wiley, 2017) Taç, Doğan; Aytaç, İsmet Arınç; Karatavuk, Ali Osman; Kuş, Melih; Ziyanak, Fırat; Artok, Levent
    Acetate derivatives of 2-en-4-yne alcohols 1 and enyne oxiranes 4 regioselectively underwent 1,5-substitution (SN2′′) reactions with Grignard reagents in the presence of an iron compound to provide vinylallenes exclusively with the (E)-configuration. An alkali salt was needed to avoid the hydride-promoted reductive 1,5-substitution pathway for 1, whereas no such additive was needed for the effective conversion of 4 into the desired alkylated or arylated vinylallene structure.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 21
    Palladium-Catalyzed Alkoxycarbonylation of Conjugated Enyne Oxiranes: a Diastereoselective Method for the Synthesis of 7-Hydroxy
    (American Chemical Society, 2015) Kuş, Melih; Artok, Levent; Aygün, Muhittin
    Palladium-catalyzed alkoxycarbonylative 1,5-substitution of conjugated enyne oxiranes provides a diastereoselective route to (E)-configured 7-hydroxy-2,3,5-trienoates. The reactions proceeded in a highly stereoselective manner, possibly through sequential formation of π-allylpalladium and σ-vinylallenyl palladium complexes. The major diastereomeric form of the product is determined by the configuration of the alkenyl moiety of the substrate.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 21
    Regio- and Stereoselective Synthesis of 2,3,5-Trienoates by Palladium-Catalyzed Alkoxycarbonylation of Conjugated Enyne Carbonates
    (American Chemical Society, 2014) Karagöz, Ezgi Şule; Kuş, Melih; Akpınar, Gürkan Eray; Artok, Levent
    Palladium-catalyzed carbonylation of 2,4-enyne carbonates in an alcohol and under balloon pressure of CO proceeds through 1,5-substitution to yield (E)-2,3,5-trienoates. The olefin geometry of the substrate is important to control the overall stereochemistry of this alkoxycarbonylation method. The reaction proceeds through successive formation of π-allylpalladium with an R3 group oriented syn and σ-allenyl palladium complexes.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Rhodium-Catalysed Alkoxycarbonylative Cyclisation Reactions of 1,6-Enynes
    (John Wiley and Sons Inc., 2011) Ziyanak, Fırat; Kuş, Melih; Artok, Levent
    The rhodium-catalysed carbonylation of 1,6-enynes possessing an electron-deficient alkenyl moiety in an alcohol reagent in the presence of a rhodium complex proceeded stereo- and chemoselectively to afford exocyclic α,β-enoates.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 15
    Rhodium- and Palladium-Catalyzed 1,5-Substitution Reactions of 2-En Acetates and Carbonates With Organoboronic Acids
    (American Chemical Society, 2011) Üçüncü, Muhammed; Karakuş, Erman; Kuş, Melih; Akpınar, Gürkan Eray; Aksın Artok, Özge; Krause, Norbert; Karaca, Sıla; Elmaci, Nuran; Artok, Levent
    Two methods involving the rhodium-catalyzed reaction of 2-en-4-yne acetates and the palladium-catalyzed reaction of 2-en-4-yne carbonates with organoboronic acids were investigated; both afforded exclusively the (E)-configured vinylallenes. The coordinative interaction of the rhodium with the acetate group promoted the δ-elimination of Rh(I)-OAc from the alkenylrhodium intermediate II in both syn and anti modes, with the syn-elimination being the major path. DFT calculations revealed that a conformer of this intermediate (II), which can lead to the (E)-configured vinylallene product via the syn-elimination mode, is energetically the most favorable conformer. The rhodium-catalyzed procedure is not applicable to reactions involving (E)-configured enyne acetates, because the geometry of the alkenylrhodium intermediate that is derived from the corresponding (E)-enyne acetate would not allow such coordinative interaction to occur. The palladium-catalyzed method, which proceeds through formation of the σ-vinylallenylpalladium intermediate, B, is suitable for both the (E)- and (Z)-configured enyne carbonates and appears to have a wider scope for both organoboronic acids and enyne substrates. The palladium-catalyzed reaction of an enantiomerically enriched enyne carbonate proceeded with racemization.
  • Article
    Citation - WoS: 37
    Citation - Scopus: 38
    Palladium-Catalyzed Alkoxycarbonylation of (z)-2 Carbonates Leading To 2,3,5-Trienoates
    (American Chemical Society, 2011) Akpınar, G. Eray; Kuş, Melih; Üçüncü, Muhammed; Karakuş, Erman; Artok, Levent
    Pd(0)-catalyzed carbonylation of (Z)-2-en-4-yn carbonates in the presence of a balloon pressure of CO in an alcohol donates vinylallenyl esters with an exclusively E-configuration and in high yields. The fact that no such reactivity could be observed with E-configured enyne carbonates may indicate that the reaction is promoted via the cooperative coordination of palladium with both alkynyl and carbonate moieties.