The photochemistry of benz[de]anthracen-7-ones. Part I. Electronic absorption and emission spectroscopy

Abstract

The electronic absorption and emission spectra of benz[de]anthracen-7-one and some of its 3-, 4-, 6-, and 8-substituted derivatives have been investigated. The lowest excited singlet states of the benzanthracenone derivatives are all π–π* in nature. 8-Aminobenz[de]anthracen-7-one has a broad, structureless, longest wavelength absorption band which disappears on protonation of the ground state. In contrast, the 6-amino-derivative possesses marked vibrational structure in its absorption spectrum and is much more resistant to protonation of the ground state