| Infrared spectroscopy was employed to measure the carbonyl stretching vibrational frequencies (vC=O) of Furfural (FUR) and2-acetyl-5-methylfuran (AMF) in single solvent and binary mixture solvents. The frequencies of absorption bands were studied to investigate the solvent-solute interactions between FUR and AMF in different solvents. The hydrogen bond effect on vibrational frequencies of C=O has been studied use quantum chemistry simulate software, the solvent effect on electronic spectrum also been calculated.In single solvent systems, the carbonyl stretching vibrations were correlated with solvent parameters which include four single empirical parameters and two multiparameter, and the applicability of the various solvent parameters in represent the solvent effect have been discussed. The result shows that the value of G has the best correlation with Uc=o of solute in all the single solvent parameters. The correlations between the uc=o and the two multi-parameter are good, and LSER relationships is most suited to describe the solvent effect. The of solvent-solute effect in binary solvent mixtures has been discussed according to the solvent-composition changes. The results showed that FUR and AMF in CHCl3/cyclo-C6H12and ROH/cyclo-C6H12solvent systems in addition to effect by non-specific (dielectric effects) interactions but also effect by specific (hydrogen bonding) interaction except in CCl4/cyclo-C6H12system.The configurations and ultraviolet absorption spectrum of FUR and AMF in different solvents have been calculated using B3LYP/6-311++G(d,p) in DFT and TD-DFT methods combined CPCM solvent model. The results showed that solvent effect has a certain impact on some properties of FUR and AMF such as configuration, atomic charges, energy and the frontier molecular orbital energy. The geometry structure of association complex of AMF and EtOH has been optimized and the influence of hydrogen bond on AMF carbonyl vibration has been discussed. |
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