Quantification of the H-Bond-Donating Ability of Trifluoromethyl Ketone Hydrates Using a Colorimetric Sensor

Trifluoromethyl ketones (TFMKs) readily form stable hydrates and hemiketals in solution, allowing them to interact with biomolecules as hydrogen-bond donors. This interaction is governed by both the hydration equilibrium and the intrinsic hydrogen-bonding strength for a given compound. The hydrogen-bond-donating abilities for aryl, heterocyclic, and alkyl TFMKs were experimentally determined by using UV-vis titrations with a colorimetric sensor. Values were also adjusted based on the percent hydrate present in solution to provide insight into the hydrogen-bond-donating ability of the hydrate species.