Electron Spin Resonance Spectra of the Radical Anions of Several 1,3hyphen;Dienes

摘要

The ESR spectra of the radical anions of 2,3hyphen;dimethylminus;1,3hyphen;butadiene, 1,3hyphen;cyclohexadiene, and isoprene have been examined in liquid ammonia. The proton hyperfine interaction can be readily assigned except for the case of isoprene where there is a small discrepancy between our assignment and the observed spectrum. In the case of 2,3hyphen;dimethylminus;1,3hyphen;butadiene two distinct CH2coupling constants are observed as might be possible for the radical anion in either ashyphen;cis, shyphen;trans,or skew conformation. Huuml;ckel theory with the inclusion of hyperconjugation is in good agreement with the observed proton coupling constants.