Ultrafast excited-state proton transfer in reversed micelles

Bioorganic Chemistry

“…Fendler to investigate the protonation of pyrene-1-carboxylic acid using a nanosecond time-resolved fluorescence technique (343). This system was used by J.H.…”

“…14. The shaded area indicates the extent of water that hydrates the surfactant head groups(343). Since the concentration of surfactant is in a very large excess over the probe, proton transfer must occur from dodecylammonium propionic acid to pyrene-l-carboxylate.…”

Bioorganic Chemistry

“…Dodecylammonium propionate (DAP) also forms reversed micelles at 0.10 M concentration in benzene and is able to entrap 0.55 M of water. This system was used by J. H. Fendler to investigate the protonation ofpyrene-1-carboxylic acid using a nanosecond time resolved fluorescence technique (161). The most striking feature of the data obtained is the extraordinarily large rate constant for the protonation of the carboxylate group in the surfactant solubilized water pool; a value ofthe order of 10 12 M -1 S -1 was observed!…”

Excited-State Proton Transfer Behavior of 7-Hydroxy-4-methylcoumarin in AOT Reverse Micelles

“…A variety of studies have been reported in the literature on this aspect. [38][39][40][41][42][43][44][45][46] Douhal et al have observed three regions in the behavior of the confined water molecules within reverse micelles using a proton transfer probe. 46 The first region is observed at w 0 values less than 2, where the shell of water bound to the surfactant head groups is mainly formed and the confinement effects dominate the relaxation dynamics of the water molecules.…”