50 years after Th. Förster, 5 years after D. Huppert and M. Eigen: proton transfer as one of the best studied chemical reactions is still under debate and paves the way for new developments in physical and theoretical chemistry.
Different protons would transfer in the excited state depending on electron-donating or electron-withdrawing substituents, leading to different luminescence mechanisms.
Cyclodextrins, saccharides, and ethanol were examined to assess the effects of hydroxy groups on the ESPT reaction. Differences in the fluorescent behaviors indicate varying interactions between the hydroxy compounds and complexes.
Emissive urea compounds with varying π-conjugation lengths were studied for their effect on excited-state intermolecular proton-transfer reactions with anions. Extended π-conjugation increases the ESPT rate constants and promotes tautomer formation.
A new classification system is used to summarise mechanisms of photochemical generation of quinone methides. Recent mechanistic studies that used ultrafast techniques are compared with old mechanistic studies that used conventional techniques.