Methylene-blue-sensitized photo-oxidation of terpenes

Abstract

Electron transfer reactions occur between the triplet state of methylene blue and some terpenes, e.g. citronellol, α-pinene and β-pinene. The rate constants k_ET for these reactions were determined but no linear correlation between ln k_ET and the ionization potentials of the terpenes was found. This finding was explained in terms of stereoelectronic effects associated with the terpenes.