Photoinduced electron transfer in two room-temperature ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF(6)) and 1-octyl-3-methylimidazolium hexafluorophosphate (OMIM-PF(6)), has been investigated using steady-state fluorescence quenching of 9,10-dicyanoanthracene with a series of single electron donors. From these fluorescence quenching rates, reorganization energy (lambda) values and k(diff) values can be derived from a Rehm-Weller analysis. In many cases, these fluorescence quenching reactions occur at rates larger than what would be expected based on the Smoluchowski equation. In addition, lambda values of 10.1 kcal/mol and 16.3 kcal/mol for BMIM-PF(6) and OMIM-PF(6), respectively, have been determined.

The dynamics of electron transfer reactions in butyl pyridinium bis(trifluoromethanesulfonyl)imide (BuPyr-NTf2) and other solvents have been explored using laser flash photolysis. In these experiments, benzophenone (BP), duroquinone (DQ), and 9-cyanoanthracene (9CA) were used as excited-state acceptors, 1,4-diazabicyclo[2.2.2]octane and hexamethylbenzene were used as ground-state donors, and methyl viologen (MV2+) was used as a probe molecule. Analysis of kinetic and spectroscopic data from these experiments shows that electron transfer from photoreduced acceptors to the probe occurs via one or more solvent ions in cases where the acceptor anion radical has a reduction potential that is more negative than the solvent ions (BP•- and 9CA•- in BuPyr-NTf2). Mediated electron transfer was demonstrated to significantly enhance quantum efficiencies of photoinduced electron transfer in cases where back electron transfer would otherwise predominate.

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The racemic product of the Betti reaction of 5-chloro-8-hydroxyquinoline, benzaldehyde and 2-aminopyridine was separated by chiral HPLC to determine which enantiomer inhibited botulinum neurotoxin serotype A. When the enantiomers unexpectedly proved to have comparable activity, the absolute structures of (+)-(R)-1 and (−)-(S)-1 were determined by comparison of calculated and observed circular dichroism spectra. Molecular modeling studies were undertaken in an effort to understand the observed bioactivity and revealed different ensembles of binding modes, with roughly equal binding energies, for the two enantiomers.