The hydrolytic reactivity of β-sultams

Abstract

N-Methyl β-sultam undergoes acid- and base-catalysed hydrolysis in water at 30 °C and I= 1.0 mol dm^–3 with k_H⁺= 2.79 dm³ mol^–1s^–1 and k_OH= 1.38 × 10^–2 dm³mol^–1 s^–1. These second-order rate constants are approximately 10⁹ and 10⁷, respectively, greater than those for a similar acyclic sulfonamide. The entropy of activation for the acid-catalysed hydrolysis of the β-sultam is –80 J K^–1 mol^–1 which may be indicative of unimolecular ring opening, whereas that for the base-catalysed reaction, –184 J K^–1 mol^–1, is consistent with a bimolecular process.