Radicals Containing a 1,4-Diselenin Ring

Cation-radicals of selenanthrene (196) are the only radicals in this category to have been observed. The ESR spectrum of the cation-radical of 196 itself, in concentrated sulfuric acid, shows no resolved proton hyperfine structure, which betokens a high spin population on Se. ° Various MO calculations bear this 

The redox properties in solution of the cation-radical of 196 and its 2,3,7,8-tetramethoxy derivative have been described. The methoxy- 

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