Observation of Distinct Carboxylic Acid Conformers in Aqueous Solution.

ABSTRACT: We investigate the molecular geometry of the carboxyl group of formic acid in acetonitrile and aqueous solutions at room temperature with two-dimensional infrared spectroscopy (2D-IR). We found that the carboxyl group adopts two distinct configurations: a configuration in which the carbonyl group is oriented antiparallel to the hydroxyl (anti-conformer), and a configuration in which the carbonyl group is oriented at an angle of ∼60° with respect to the hydroxyl (syn-conformer). These results constitute the first experimental evidence that carboxyl groups exist as two distinct and long-living conformational isomers in aqueous solution at room temperature.

SUBMITTER: Giubertoni G 

PROVIDER: S-EPMC6589744 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature