Excited state aromatization assisted push-pull abilities of two unsaturated oxazolone derivatives

KARABIYIK H., ÖZTÜRK ÜRÜT G., SEVİNÇEK R.

JOURNAL OF SAUDI CHEMICAL SOCIETY, cilt.22, sa.5, ss.519-526, 2018 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 22 Sayı: 5
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1016/j.jscs.2017.09.001
  • Dergi Adı: JOURNAL OF SAUDI CHEMICAL SOCIETY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.519-526
  • Anahtar Kelimeler: TD-DFT, Aroma ticity, CDA, Azlactones, HOMHED, DONOR-ACCEPTOR INTERACTIONS, DENSITY-FUNCTIONAL THEORY, PI-CONJUGATED SYSTEMS, OPTICAL BEHAVIOR, AROMATICITY, CHROMOPHORES, ORBITALS, BONDS
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

Molecular structures of two unsaturated oxazolone derivatives involving furan rings, which are decorated with p-tolyl (FurM) and 4-nitro phenyl (FurN), were investigated by X-ray crystallography and quantum chemical calculations. Their ground and excited states were examined by DFT and TD-DFT computations with the aid of topological electron density studies, NBO and Charge Decomposition Analysis. Both compounds have push-pull (D-pi-A) framework using oxazolone ring as pi-linker. Depending on the transitions from the ground to excited states, intramolecular charge transfer (ICT) in both compounds results in aromatization of oxazolones. Push-pull ability of FurN has more pronounced than that of FurM. The use of furan instead of almost fully aromatic benzenoid ring reduces HOMO-LUMO band gap due to relatively low aromaticity level of furan. Introduction of nitro substituent leads to a further reduction in HOMO-LUMO gap. In addition, electronic redistribution in the excited state results in aromatization of oxazolone moieties without elongation of carbonyl bonds. (C) 2017 King Saud University. Production and hosting by Elsevier B.V.