Picosecond kinetics of the excited-state intramolecular proton transfer reaction: Confirmation of the intrinsic potential barrier in 2,5-bis-(benzoxazolyl)-hydroquinone

✍ Scribed by Anna Grabowska; Andrzej Mordziński; Naoto Tamai; Keitaro Yoshihara

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 330 KB
• Volume: 153
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(88)85230-8

✦ Synopsis

The kinetics of previously reported excited-state intramolecular proton transfer (ESIPT) reactions were investigated using single-photon counting techniques of high temporal resolution: 2,5-bis-( benzoxazolyl)-hydroquinone undergoing single PT emits two fluorescence bands, the primary (450 nm) and tautomeric (603 nm). The bimodal kinetics of the equilibrated reversible reaction was confirmed as well as the intramolecular character of the primary emission. Two kinetic components were detected: one representing forward and back PT reactions ( = 20 ps), and the second representing the common decay of Its partners ( x 960 ps). The kinetics of an ESIPT has thus been directly observed at room temperature.