Nucleophilic substitution of Bromo-p-benzoquinones by dimethylamine

Abstract

Product analysis shows that dimethylamine, like methoxide anion, substitutes bromo-p-benzo-quinones by an addition-elimination process, resulting in isomeric dimethylaminoquinones. Bromo- dimethylaminoquinones were also formed, due to incomplete elimination of hydrogen bromide. In contrast to the substitution by methoxide the product distribution is largely unaffected by changing to a dipolar aprotic solvent.     The e.s.r. spectra of 2-t-butyl-5-(N,N-dimethylamino)-1,4-benzosemiquinone and two related semiquinones have been analysed.