Radicals Containing a Selenophene Ring

Dibenzoselenophene anion-radical (190) is the only radical of this class whose ESR spectrum has been analyzed. Two groups found essentially the same proton hyperfine splittings. Those indicated in gauss in 190 were given by Chiu and Gilbert who also measured the Se splitting their spectrum was obtained by reduction of the heterocycle with potassium in DME. A low temperature (------50°C) was necessary in order to obtain 

The occurrence of selenophene-2-carboxaldehyde ketyl, or its conjugate acid, during polarographic reduction of the parent aldehyde in aqueous ethanol at a mercury cathode is implied by the observation of two one-elojtron reduction waves and the formation of 1,2-di(selenol-2-yl)ethane-l, 2-diol as principal product.  

Single-electron reduction steps have been observed for various heterocyclic quinones such as 191.  

Radicals Containing a Five-Membered Heterocycle 1. Radicals Containing a Selenophene Ring 

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