Nitrogen-substituted phthalimides: fluorescence, phosphorescence, and the mechanism of photocyclization

Abstract
From u.v. absorption and fluorescence measurements it is suggested that N-(dialkylaminomethyl)phthalimides fluoresce(weakly) from the second excited singlet state (π,π*), and that the lowest energy singlet state (n, π*) is non-fluorescent. Phosphorescence occurs from the lowest triplet state at 77 K, and in ethanol solution this state is unambiguously assigned a (π,π*) configuration. The second triplet state (n, π*) is quite close in energy to the first. The luminescence results point to the operation of an initial electron transfer step in the photochemical cyclization reaction of these phthalimides.
Keywords

This publication has 0 references indexed in Scilit: