KINETIC-STUDIES OF HYDROLYSIS OF SOME ALKYL BENZENESULFINATES

Hydrolysis reactions of methyl, ethyl, isopropyl, and t-butyl benzenesulfinates were kinetically investigated. Rates of alkaline hydrolysis decrease with increasing steric effects (Me > Et > i-Pr > t-Bu), while the t-butyl ester is the most reactive in perchloric acid (t-Bu > Me > Et > i-Pr). The hydrolysis is faster in HCI and HBr than in HClO4, and the relative rates in the halide acids are not unusual (Me > Et > i-Pr approximately t-Bu). The high reactivity of the t-butyl ester in HClO4 is ascribed to the reaction at the carbon via the Al mechanism, while halide ions accelerate the hydrolysis by nucleophilic participation at sulfur.