220 MHz nuclear magnetic resonance analysis and selective deuteriodeprotonation of benzo[a]pyrene and 6-methylbenzo[a]pyrene

Abstract

An analysis of the 220 MHz magnetic resonance spectra of the carcinogenic benzo[a]pyrene (1) and 6-methylbenzo[a]pyrene (2) is presented. A study of proton exchange in sulphuric [²H₂]acid is used to determine the specific positions of electrophilic substitution. Electrophilic attack on compound (1) takes place predominantly at the 6-position, and then at the 1- and 3-positions, whereas in compound (2) the most active positions are C-1, C-3, and C-5, with C-5 the least active of the three.