Reinvestigation of solvent catalyzed ground-state reverse proton transfer in 7-hydroxyquinoline

The dynamics of the ground-state reverse proton transfer of 7-hydroxyquinoline have been reinvestigated in various alcohol solvents by pulse pump-cw probe transient absorption in combination with two-step laser-induced fluorescence measurements. The results show a nearly temperature-independent kinetic isotope effect for the reverse proton transfer in the ground state, consistent with the previous study. The overall proton transfer dynamics can be rationalized based on a kinetic derivation incorporating solvent reorganization forming a specific cyclic solvent/solute complex, and then the dissociation and actual proton transfer of this hydrogen bonded complex.