Structural, vibrational spectra and normal coordinate analysis for two tautomers of 4(5)-(2’-furyl)-imidazole

A. E. LEDESMA; J. ZINCZUK; J. J. LÓPEZ GONZÁLEZ; A. BEN ALTABEF; S. A. BRANDÁN

JOURNAL OF RAMAN SPECTROSCOPY

John Wiley & Sons, Ltd

Año: 2010 vol. 41 p. 587 - 597

0377-0486

We have prepared 4-(2-furyl)-1-methylimidazole (1) and characterized it by infrared, Raman, multidimensional nuclear magnetic resonance and mass spectroscopies. Employing density functional theory (DFT)/B3LYP with Pople’s basis set, the molecular structures of the compound have been theoretically determined in gas phase. The harmonic vibrational frequencies for the optimized geometries were calculated at DFT/B3LYP/6-31G* and 6-311++G** level in the approximation of the isolated molecule. Then, in order to get a good assignment of the IR and Raman spectra in solid phase of 1, the best fit possible between the calculated and recorded frequencies and the corresponding force field were scaled using the Pulay et al. Scaled quantum mechanical force field (SQMFF) methodology. The most stable structure of the compound was justified by means of natural bond orbital (NBO) and atoms in molecules (AIM) studies