Photochemistry of “Super” Photoacids. 2. Excited-State Proton Transfer in Methanol/Water Mixtures
Citations Over TimeTop 10% of 2000 papers
Abstract
Excited-state proton transfer to solvent (PTTS) of 5-cyano-2-naphthol was investigated in methanol/water mixtures. We have found that the time-resolved fluorescence data fit the solution of the Debye−Smoluchowski equation for the reversible geminate recombination of ions over the whole range of methanol/water concentration ratios. The rate constants of the elementary protolytic photochemical processes and their isotope effects were determined by a simultaneous analysis of the time-resolved fluorescence of the photoacid and its conjugated anion. The competition between adiabatic protonation and quenching of the excited naphtholate anion by the geminate proton was observed to diminish sharply near pure methanol. The dissociation rate coefficient near pure methanol depends on a power of the water concentration, which appears to decrease from 2 (for “ordinary” photoacids) to below 1 for “super” photoacids.
Related Papers
- → Terminal vs Bridging Hydrides of Diiron Dithiolates: Protonation of Fe2(dithiolate)(CO)2(PMe3)4(2012)128 cited
- → Protonation of homotroponeiron tricarbonyl and cyclooctatrienoneiron tricarbonyl complexes(1980)8 cited
- → 13C nuclear magnetic resonance study of the protonation of 2,2,4-trimethyl-1,5,9-triazacyclododecane(1988)6 cited
- → The effect of substitution on protonation sites: evidence for protonation at N(3) in N(7)-substituted adenine(1975)6 cited
- The Protonation Equili rium and Decomposition of Amino- and Hydroxyphosphonates, Phos phine Ox ides and Phosphonic Acid(2007)