Combined experimental and quantum chemical studies on spectroscopic (FT-IR, FT-Raman, UV–Vis, and NMR) and structural characteristics of quinoline-5-carboxaldehyde

Kumru M., Altun A., Kocademir M., Küçük V., Bardakçı T., Şaşmaz İ. B.

Journal of Molecular Structure, cilt.1125, ss.302-309, 2016 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 1125
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1016/j.molstruc.2016.06.066
  • Dergi Adı: Journal of Molecular Structure
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.302-309
  • Anahtar Kelimeler: Density functional theory, Hatree-Fock, NMR, Quinoline-5-carboxaldehyde, UV–Vis, Vibrational spectra
  • İstanbul Gelişim Üniversitesi Adresli: Hayır

Özet

Comparative experimental and theoretical studies have been performed on the structure and spectral (FT-IR, FT-Raman, UV–Vis and NMR) features of quinoline-5-carboxaldehyde. Quantum chemical calculations have been carried out at Hartree-Fock and density functional B3LYP levels with the triple-zeta 6-311++G** basis set. Two stable conformers of quinoline-5-carboxaldehyde arising from the orientation of the carboxaldehyde moiety have been located at the room temperature. The energetic separation of these conformers is as small as 2.5 kcal/mol with a low transition barrier (around 9 kcal/mol). Therefore, these conformers are expected to coexist at the room temperature. Several molecular characteristics of quinoline-5-carboxaldehyde obtained through B3LYP and time-dependent B3LYP calculations, such as conformational stability, key geometry parameters, vibrational frequencies, IR and Raman intensities, UV–Vis vertical excitation energies and the corresponding oscillator strengths have been analyzed. The 1H and 13C NMR chemical shifts of quinoline-5-carboxaldehyde were also investigated.