Molecular structure of (Z)-6-[(5-chloro-2-hydroxyphenylamino) methylene]-3-(diethylamino)cyclohexa-2,4-dienone: A combined experimental and theoretical study


KOŞAR B., Albayrak C., ODABAŞOĞLU M., Buyukgungor O.

JOURNAL OF MOLECULAR STRUCTURE, cilt.989, sa.1-3, ss.31-37, 2011 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 989 Sayı: 1-3
  • Basım Tarihi: 2011
  • Doi Numarası: 10.1016/j.molstruc.2010.12.031
  • Dergi Adı: JOURNAL OF MOLECULAR STRUCTURE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.31-37
  • Anahtar Kelimeler: Schiff base, Tautomerism, Intramolecular proton transfer, HOMA, DFT, SCHIFF-BASES, SOLID-STATE, TAUTOMERIC EQUILIBRIUM, CRYSTAL-STRUCTURE, PROTON-TRANSFER, DENSITY, HYDROXYSEMICARBAZIDE, PERFORMANCE, DERIVATIVES, INHIBITION
  • Ondokuz Mayıs Üniversitesi Adresli: Evet

Özet

The crystal structure and spectroscopic properties of ortho-hydroxy Schiff base compound (Z)-6-[(5-chloro-2-hydroxyphenylamino)methylene]-3-(diethylamino)cyclohexa-2,4-dienone were determined by X-ray diffraction, IR and UV-Vis spectroscopy techniques. Molecules of the compound exist as NH tautomeric form in solid state. The gas phase geometry optimizations of two possible tautomeric forms of the title compound were achieved using OFT calculations at B3LYP/6-31G(d,p) level of theory. In order to describe the potential energy barrier belonging to the intramolecular proton transfer and to observe the effects of transfer on the molecular geometry, a relaxed potential energy surface (PES) scan was performed based on the optimized geometry of the NH tautomeric form by varying the redundant internal coordinate, N-H bond distance. At the same level of theory, the vibrational frequencies were calculated and compared with the experimental frequencies. The electronic absorption spectra of the tautomers were calculated using time-dependent density functional theory (TO-OFT) method started from solution phase optimized geometries and compared with the experimental ones. Crown Copyright (c) 2010 Published by Elsevier B.V. All rights reserved.