Nanosecond Flash Photolysis of Unsymmetrical Phenol-Substituted Calix4Arene in Cyclohexane

摘要

In the present paper the laser flash photolysis study of an unsymmetrical hindered phenol-substituted calix[4]arene(UPCA[4]OH) at 248 nm was carried out in cyclohexane at room temperature. The transient absorption spectra of UPCA[4]OH displayed two main absorption maxima at ca.330 nm and 520 nm with different grow and decay kinetics, and initial peak 520 nm was assigned to the triplet state of the solute and the other peak at 330 nm was due to unsymmetrical phenol-substituted calix[4]aryloxyl radical. According to the kinetic analysis, the mechanism of theformation of he triplet and the calix[4]aryloxyl radical has been proposed.