The prototropic tautomerism in 2-hydroxypridine represents a model for the study of conformational and tautomeric equilibria. The stability of the different species is governed by the balance between electronic and resonance effects and can be greatly influenced by ring substitutions and the presence of solvents.
In particular, chlorination in different ring positions and changes in solvent polarity cause a shift of the equilibrium, therefore changing the relative abundances between isomers.
This work was a collaboration with the group of Sonia Melandri at the University of Bologna.
The investigation is being published in Chem. Eur. J