ESR STUDIES OF A NEW STABLE PI-CONJUGATED BIS-ARYLOXYL BIRADICAL

The new stable π-conjugated bisaryloxyl biradical, 4,4′-(m-phenylene) bis(2,6-di-t-butylphenoxyl), was prepared, and the g- and D-tensor values of the biradical were determined from an analysis of an asymmetric ESR spectrum of a frozen solution containing the biradical. A resolved hyperfine structure was observed in the ESR spectrum of a liquid solution of the biradical, giving the hyperfine splitting values theoretically expected for the triplet state of the biradical.