title: Theoretical and spectroscopic studies on molecular structure and hydrogen bonding of 2-trifluoroacetylphenol.
abstract: The molecular structure, intramolecular hydrogen bonding, and vibrational frequencies of 2-trifluoroacetylphenol (TFAP), were investigated by means of density functional theory (DFT) calculations and NMR, IR, and Raman spectroscopy techniques. The calculated theoretical and observed experimental results were compared with the corresponding data for salicylaldehyde (SA). Calculations were performed at the B3LYP level, using 6-311++G(**) basis set. The observed vibrational frequencies of TFAP were assigned with aid of theoretical calculations. The scaled frequencies at the B3LYP/6-311++G(**) level are in good agreement with the corresponding observed values by acceptable deviations. To investigate the effect of CF3 group on the hydrogen bond strength, the charge distributions, steric effects, and electron delocalization in TFAP and SA are studied using the natural bond orbital (NBO) analysis. The computations were further complemented with an atoms-in-molecules (AIM) topological analysis to characterize the nature of the intramolecular hydrogen bond, IHB, in the considered molecules. The contradiction between experimental and theoretical results was interpreted by considering the opposite effects of steric effect and electron withdrawing nature of CF3 group.
authors.affiliation: Chemistry Department, Shahrood University, Shahrood 3619995161, Iran.
authors.forename: Zainab
authors.initials: Z
authors.lastname: Moosavi-Tekyeh
authors.affiliation: Chemistry Department, Shahrood Branch, Islamic Azad University, Shahrood, Iran. Electronic address: sftayyari@gmail.com.
authors.forename: Sayyed Faramarz
authors.initials: SF
authors.lastname: Tayyari
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D004583:Electrons; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D010636:Phenols / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014732:Vibration
chemical_list: C000598770:2-trifluoroacetylphenol; D000447:Aldehydes; D006845:Hydrocarbons, Fluorinated; D010636:Phenols; C013243:salicylaldehyde
keywords: 2-Trifluoroacetylphenol; AIM; Intramolecular hydrogen bonding; NBO; Vibrational assignment