engleski

Localization of the counterion of the protonated Schiff base of n-butylretinal in solution

The vibrational spectra of the protonated Schiff base of n-butylretinal (nSBR+) in dichloromethane are studied. The trifluoroacetic acid (TFA) is used for the protonation of the Schiff base of n-butylretinal (nSBR). Combining the two-dimensional correlation analysis of the experimental infrared spectra with anharmonic frequency calculations it is shown that two types of ionic aggregates between nSBR+ and the TFA counterion are formed. The study suggests that the interaction between nSBR+ and the TFA counterion may be responsible for the observed lost of photoselectivity in the trans-cis isomerization of the nSBR+ in solution.

n-butylretinal ; trifluoroacetic acid ; infrared spectroscopy ; hydrogen bonding ; DFT ; anharmonic frequency

nije evidentirano