Photochemical reaction of harmalol. Part 2. Electronic spectra

Abstract

Electronic spectra (absorption, emission and excitation fluorescence spectra) of harmalol in organic solvents have been recorded. The unusual behaviour of this alkaloid has been studied by excited state proton transfer from organic solvents. The effect of the presence of water in the organic media on the electronic spectra and on the prototropic equilibria in the ground and excited singlet states are discussed briefly, as well as those owing to the presence of acidic and basic impurities in the organic media on the, electronic spectra. Harmol was selected to be used as a model compound. Emission and excitation spectra of both alkaloids in an adsorbed phase and in the solid state are also described.