Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 2Citation - Scopus: 2Palladium-Catalysed Regio- and Stereoselective Arylative Substitution of Gamma,delta-Epoxy Esters and Amides by Sodium Tetraaryl Borates(Royal Society of Chemistry, 2020) Bilgi, Yasemin; Kuş, Melih; Artok, LeventPalladium-catalysed reactions of gamma,delta-epoxy-alpha,beta-unsaturated esters and amides with NaBAr(4)reagents proceeded regio- and stereoselectively, producing allylic homoallyl alcohols with aryl-substituents in the allylic position for a wide range of substrates. AsPh(3)was found to be a competent ligand for the arylation reaction, whereas phosphine ligand/Lewis acidic organoboron combinations favoured the substitution reaction by oxygen nucleophiles (e.g.H2O, ROH).Article Citation - WoS: 6Citation - Scopus: 6Palladium-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, LeventA 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: 9Citation - Scopus: 10Iron-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, LeventAcetate 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: 21Citation - Scopus: 21Palladium-Catalyzed Alkoxycarbonylation of Conjugated Enyne Oxiranes: a Diastereoselective Method for the Synthesis of 7-Hydroxy(American Chemical Society, 2015) Kuş, Melih; Artok, Levent; Aygün, MuhittinPalladium-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: 21Citation - Scopus: 21Regio- 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, LeventPalladium-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: 7Citation - Scopus: 7Rhodium-Catalysed Alkoxycarbonylative Cyclisation Reactions of 1,6-Enynes(John Wiley and Sons Inc., 2011) Ziyanak, Fırat; Kuş, Melih; Artok, LeventThe 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: 14Citation - Scopus: 15Rhodium- 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, LeventTwo 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: 37Citation - Scopus: 38Palladium-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, LeventPd(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.Article Citation - WoS: 15Citation - Scopus: 14Rhodium Catalysed Chemo- and Stereoselective Arylative and Alkenylative Cyclisation Reactions of Unsymmetric Diynes Containing a Terminal Alkyne Moiety With Organoboronic Acids(Royal Society of Chemistry, 2010) Artok, Levent; Kuş, Melih; Ürer, Bağdagül N.; Türkmen, Gülşah; Aksın Artok, ÖzgeUnsymmetric diynes possessing a terminal alkyne moiety reacted with organoboronic acids both chemo- and stereoselectively to afford arylated or alkenylated exocyclic dienes by catalysis from the [Rh(cod)OCH 3] 2 complex. The use of a polar protic solvent, e.g. CH 3OH is required for the success of the process under mild conditions. © 2010 The Royal Society of Chemistry.Article Citation - WoS: 11Citation - Scopus: 2Synthesis of Α,β-Unsaturated Ketones by Rhodium-Catalyzed Carbonylative Arylation of Internal Alkynes With Arylboronic Acids(Georg Thieme Verlag, 2008) Kuş, Melih; Aksın Artok, Özge; Ziyanak, Fırat; Artok, LeventThe Rh-catalyzed reaction of arylboronic acids with internal alkynes under a CO atmosphere in the presence of an acid additive afforded α,β-unsaturated ketones as the major products. Hydroacylation of internal alkynes, except in the case of diaryl acetylenes, proceeded in syn fashion, yielding the E-configured isomer. A mixture of E- and Z-isomers was obtained with diphenyl acetylene. Reactions were also highly regioselective for various nonsymmetric alkynes.