Collect. Czech. Chem. Commun. 2006, 71, 1445-1452

Hydrolysis of O-Acetylsalicylic Acid (Aspirin) in Relation to the Aspirin-Bromate-Acid Oscillating System

Ľubica Adamčíková*, Daniel Mišicák and Peter Ševčík

Department of Physical and Theoretical Chemistry, Faculty of Natural Sciences, Comenius University, Mlynská dolina, 842 15 Bratislava, Slovak Republic


The uncatalyzed BrO3--O-acetylsalicylic acid (aspirin) reaction in aqueous H2SO4 exhibits oscillatory behavior. The induction period observed before the onset of oscillations depends on the extent of hydrolysis of aspirin. The rate constant of hydrolysis of aspirin was determined indirectly from the value of induction period. When aspirin undergoes hydrolysis, the degradation products are salicylic acid and acetic acid. Salicylic acid may play a role of "active" substrate responsible for the oscillations. Aspirin (Bayer) generates also oscillations with bromate.

Keywords: Chemical oscillators; Uncatalyzed bromate oscillator; Bromate; Aspirin; Kinetics; Esters hydrolysis.

References: 14 live references.