Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Author: search.filters.author.Elmacı, NuranPublisher: search.filters.publisher.John Wiley and Sons Inc.

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  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Transition-Metal Direct C-H Arylation of Thiophene in Aqueous Media Via Potassium Peroxymonosulfate
    (John Wiley and Sons Inc., 2019) Özenler, Sezer; Özenler, Sezer; Kaya, Hakan; Yıldız, Ümit Hakan; Elmacı, Nuran; Elmacı Irmak, Nuran; Yıldız, Ümit Hakan; 04.01. Department of Chemistry; 01. Izmir Institute of Technology; 04. Faculty of Science
    This study covers the use of potassium peroxymonosulfate (PPS) which, is a mild and inexpensive catalyst, for direct coupling of C-H/C-H for water soluble thiophene. The 3-(4-methyl-3 '- thienyloxy)propyltriethylammonium bromide (M1) has been selected as model monomer that reacted PPS in 2.0, 0.20 and 0.020 monomer to PPS ratio. The reaction has been monitored via NMR spectroscopy revealing the monomer consumption and formation of dimers to tetramers as well as completion of reaction within 15 minutes. Resultant product is easily collected without tedious work up steps. The computational calculation has optimized the regularity of the coupling as head to tail, tail to tail, head to tail (HT-TT-HT) for tetramer. The regularity of tetramer which is further satisfied via NMR analysis showing emergence of new peaks at 3.56 and 4.48. The shifts in the UV maximum of reactive species have been monitored by absorbance spectroscopy showing time dependent red shift corresponds to growing from monomer to tetramers. The reaction has self-stopped due to low solubility of moderate condensates (higher than trimer), however further experiments have performed in water-organic mixtures showed great promises to obtain higher condensates.
  • Article
    Citation - WoS: 16
    Citation - Scopus: 19
    N,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 Irmak, Nuran; Lüthi, Hans Peter; Diederich, François; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of Technology
    The 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.