INFRARED STUDY OF PHENYL ACETATE IN DILUTE-SOLUTIONS

Two bands of significant intensity are observed for phenyl acetate in CHCl3 and/or CCl4 solution. The experimental data indicate that the two bands result from carbonyl stretching in Fermi resonance (FR) with a combination tone, and the amount of FR interaction changes with change in the mole % CHCl3/CCl4 or from change in the reaction field of the CHCl3/CCl4 solution. In general the (v)C = O frequencies decrease as the acceptor number (AN) of the solvent increases. The correlation is not linear, and it is suggested that steric factors hindering the intermolecular association between solute and solvent are involved in these cases. However, in alcohol solutions intermolecular hydrogen bonding between the alcoholic OH proton and the carbonyl group of phenyl acetate (ROH:O = C) is a contributing factor to this nonlinear correlation.