Electrochemical determination of new Hammett σ constants corresponding to PhSe, PhTe, Se–, and Te– substituents

Abstract

Hammett σ_m and σ_p constants for PhTe and Te^– substituents have been derived and compared with those of the Se homologues derived from the half-wave potential shift of the first reduction step of phenylchalcogenobenzophenone and the third reduction step of symmetrical bis(cyanophenyl) chalcogenide. For the PhTe, PhSe, Te^–, and Se^– substituents, the σ_m values are 0.20, 0.20, –0.57, and –0.59 and the σ_p values are 0.29, 0.22, –0.72, and –0.84, respectively. The σ_p value of the Te^– group and all of the σ_m values have been determined for the first time.