T. Sakurai, H. Mizuno, T. Kubota
Jul 1, 1991
Citations
0
Influential Citations
7
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Title hydroxylamines (1) undergo benzophenone-sensitized photolysis to give N-benzylidenebenzylamine (2), p-substituted benzoic acids (3), and monosubstituted benzenes (4) derived from decarboxylation of p-substituted benzoyloxyl radicals. Analysis of the linear Stern–Volmer plots, both for the sensitized photolysis of 1 and for the phosphorescence quenching of benzophenone by 1, demonstrates the participation of triplet 1 in this photolysis. The logarithm of the ratio (kr⁄kd), where kt is the rate constant for homolytic cleavage of the N–O bond in triplet 1 and kd is that for its deactivation, used as a measure of the triplet-state reactivities of 1, exhibited a good Hammett-type relationship against the substituent constant (σ) with a slope (ρ) of −0.75. This indicates the exclusive occurrence of homolysis of the N–O bond in the first excited triplet state of 1. Thus the decomposition of 1 activated by triplet benzophenone is classified as an imine-forming radical elimination. The results of deuterium i...