14558-12-4Relevant academic research and scientific papers
A practical scale for measuring the acidity of media for the generation of radical cations for EPR spectroscopy
Eberson, Lennart,Persson, Ola
, p. 395 - 398 (2007/10/03)
1,4,5,8-Tetramethylnaphthalene (1) undergoes a facile rearrangement first to 1,3,5,8-tetramethylnaphthalene (3) and then to other tetramethylnaphthalenes upon treatment with Bronsted and/or Lewis acids, but is stable toward rearrangement at the radical cation level (1?+). By measuring the rate constant of the rearrangement of 1→3, a practical scale of the Bronsted/Lewis acidity of certain oxidant-solvent combinations commonly used to generate radical cations for EPR spectroscopy can be established. The results show that the reactivity falls in the order AlCl3CF3SO3H>H2SO 4>H3O+CF3COOH≈SbCl 3. Antimony pentachloride does not catalyze the rearrangement but acts as a chlorinating agent. Acta Chemica Scandinavica 1996.
