Spectroscopic Studies on the Intramolecular Hydrogen Abstraction Reactions of n-Alkyl Anthraquinone-2-carboxylates

Abstract

Abstract Chain length dependence of the intramolecular hydrogen abstraction reaction of n-alkyl anthraquinone-2-carboxylates (AQ-n, n=2–20) has been studied by steady-state photolysis, phosphorescence, laser flash photolysis, and two-step laser induced fluorescence spectroscopies. All the results indicate that the excited triplet of the anthraquinone chromophore abstracts a hydrogen atom from its methylene side chain, whose rate increases with increasing chain length. The rate constant of AQ-8 is 1×104 s−1 and the increase in the rate is about 1.5×104 s−1 per one additional methylene unit for n≥10.