Konformation sterisch gehinderter Anilin-Kationradikale und Benzyl-Kationen/On the Conformation of Sterically Hindered Aniline Cation Radicals and Benzyl Cations

Abstract A series of aniline cation radicals have been generated in a flow apparatus, and their ESR spectra have been recorded and interpreted. The data show that the NR1R2 substituents are less twisted in these systems than the CR1R2 substituents in the isoelectronic but sterically less hindered benzyl radicals, in accordance with MNDO calculations. The conformations of these systems are strongly influenced by electronic π-resonance effects which limit the usefulness of steric models for structural predictions. The results suggest that the CR1R2 substituent in the benzyl cations is less twisted than in the corresponding radicals. An ESR measurement of these radicals should therefore provid…