The Hammett Acidity Function H0 of Trifluoromethanesulfonic Acid-Trifluoroacetic Acid and Related Acid Systems: A Versatile Nonaqueous Acid System

Abstract

The acidity function (H0) of mixtures of trifluoromethanesulfonic acid (TFSA) and trifluoroacetic acid (TFA) was measured. Nonaqueous acid systems based on TFSA, which is distillable, stable, non-oxidative and only weakly nucleophilic, can cover a wide range of acidity comparable to that of aqueous sulfuric acid, and should be useful for mechanistic and synthetic studies in organic chemistry. An H0value lower than-16 could be obtained by adding a small amount of SbF5 to TFSA. © 1991, The Pharmaceutical Society of Japan. All rights reserved.