Mid- and near-infrared study of hydrogen bond complexes between phenols and N,N-dimethylformamide
1998; Elsevier BV; Volume: 18; Issue: 1 Linguagem: Inglês
10.1016/s0924-2031(98)00038-1
ISSN1873-3697
AutoresZ. Pawełka, Th. Zeegers‐Huyskens,
Tópico(s)Free Radicals and Antioxidants
ResumoThe mid- and near-infrared spectra of hydrogen bond complexes between phenol derivatives and N,N-dimethylformamide are investigated. The enthalpies of complex formation determined in carbon tetrachloride range from 23 to 26.6 kJ mol−1. Some spectroscopic features observed in the mid- and near-infrared region are discussed. The first overtone of the ν(OH…O) vibration is very broad and characterized by several submaxima which are tentatively assigned to a coupling between high and low frequency modes. The anharmonicities of the ν(OH…O) vibration determined from the experimental frequencies observed in the mid-infrared and near-infrared region range between 117 and 150 cm−1. The correlation between the enthalpies and experimental or harmonic frequency shifts is discussed. Comparison with complexes involving the same proton donors and N-methyldiacetamide shows that the anharmonicity roughly increases with the hydrogen bond strength.
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