EXCITED STATE INTERACTIONS OF 7‐AZAINDOLE WITH ALCOHOL AND WATER

Abstract
Abstract— The fluorescence spectrum of 7‐azaindole in alcohol is composed of two fluorescence bands. Effects of pH, temperature and solvent deuteration on the fluorescence spectra and quantum yields of 7‐azaindole and other model compounds in ethanol and in water are reported. The long wavelength band arises from a tautomeric species formed in an adiabatic photoreaction involving double proton transfer between one molecule of 7‐azaindole and one molecule of alcohol.The fluorescence spectrum of 7‐azaindole in water is composed of only one band, but the emission is weak and shows a large solvent isotope effect. The possibility of a double proton transfer reaction between 7‐azaindole and water is discussed.