Abstract

The 1H- and 13C-NMR spectra of three substituted N-(4-hydroxyphenyl)pyridinium perchlorates, precursors of solvatochromic 4-pyridiniophenolate betaines, were recorded in deuterated acetone, dimethylsulfoxide, and acetonitrile, and their spectral behavior in these solvents was analyzed as evidence of the solute-solvent interactions present in solution. The effect of the increasing orthogonality between the phenolic and pyridinium fragments was clearly evident from the obtained spectra, thus shedding light on the ground-state structures of their deprotonated solvatochromic derivatives and their interactions with the solvent.