Femtosecond intramolecular proton transfer in photoexcited mono- and dienol derivatives of bipyridine

A femtosecond study of the intramolecular proton transfer dynamics in photo excited mono- and dienol derivative compounds of pyridine is reported. It i s shown that when a strongly electron-withdrawing substituent is attached t o [2,2'-bipyridyl]-3,3'-diol, the excited-state proton transfer of this com pound is changed from a double-proton transfer to a single-proton transfer. The excited-state single-proton transfer time in the title compounds is < 150 fs. (C) 1999 Elsevier Science B.V. AU rights reserved.