Scavenging of the radical species formed in the sonochemical excitation of styrenes

The sonochemical excitation of 4-substituted styrenes in acetic acid was studied by quenching the radical species with pyrocatechol. The rate-limiting vaporization step, evidenced by the linear free energy relationship (LFER) between the excitation and the vapor pressure of the styrenes, is a characteristic of the sonochemical reactivity in a homologous series of substrates.