Photochemically Generated Free Radicals. I. The Perinaphthenone System

Abstract

The photolysis of perinaphthenones in 2-propanol generates the corresponding hydroxyperinaphthenyl radicals which are relatively stable at room temperature. The electron spin resonance spectra can in most cases be interpreted in terms of splitting by two distinct groups of protons. Under high-resolution conditions small differences within these groups become apparent, and splitting by hydrogen on oxygen is observed. Detailed assignments are made on the basis of McLachlan MO—SCF calculations. The data indicate that |QOH|≈7 G. The same value is obtained by a calculation based on the configuration-interaction model of McConnell.