Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
4 results
Search Results
Now showing 1 - 4 of 4
Article Citation - WoS: 1Citation - Scopus: 1Rhodium(i)-Catalyzed Co-Gas Arylative Dual-Carbonylation of Alkynes With Arylboronic Acids Via the Formyl C-H Activation of Formaldehyde(Georg Thieme Verlag, 2021) Morimoto, Tsumoru; Wang, Chuang; Tanimoto, Hiroki; Artok, Levent; Kakiuchi, KiyomiThe rhodium(I)-catalyzed reaction of alkynes with aryl-boronic acids in the presence of formaldehyde results in a CO-gas-free arylative dual-carbonylation to produce gamma-butenolide derivatives. The simultaneous loading of phosphine-ligated and phosphine-free rhodium(I) complexes is required for efficient catalysis. The former complex catalyzes the abstraction of a carbonyl moiety from formaldehyde through the activation of its formyl C-H bond (decarbonylation) and the latter catalyzes the subsequent dual-incorporation of the resulting carbonyl unit (carbonylation). The use of larger amounts of the phosphine-ligated rhodium(I) complex generates more carbonyl units, leading to the formation gamma-butenolides via the dual-incorporation of the carbonyl unit.Article Citation - WoS: 13Citation - Scopus: 14Rhodium(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, LeventThe 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: 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.Article Citation - WoS: 16Citation - Scopus: 19N,n-Dialkylaniline Tetraethynylethenes: a New Class of Chromophores Possessing an Emitting Charge-Transfer State. Experimental and Computational Studies(John Wiley and Sons Inc., 2001) Gobbi, Luca; Elmacı, Nuran; Lüthi, Hans Peter; Diederich, FrançoisThe photophysical properties of N,N-dimethylaniline- (DMA) substituted tetraethynylethene (TEE; 3,4-diethynylhex-3-ene-1,5-diyne) and related derivatives were investigated in a joint experimental and computational study. Measurements of the electronic emission spectra showed that these novel chromophores display a dual fluorescence which strongly depends on solvent polarity. Computational studies suggest that the twisted intramolecular charge-transfer state (TICT) model offers a possible explanation for the experimentally observed dual fluorescence. Time-dependent density functional calculations revealed that the initial excited state reached upon photoirradiation relaxes to a lower-energy TICT state in which either the dimethylamino group is twisted into an orthogonal position with respect to the remaining planar arylated TEE moiety or the entire DMA donor group takes an orthogonal orientation with respect to the rigid, planar TEE acceptor moiety. For the compounds investigated, the charge-transfer state responsible for the strongly solvent-dependent luminescence is directly connected with the initial excited state, namely, no crossing of states is involved.