Solvent effects on the 14N hyperfine coupling constants and spin exchange rates for di-t-butyl nitroxide and peroxylamidisulphonate ions [(O3S)2NO2–

Abstract

Solvent effects on the 14N hyperfine coupling for solutions of di-t-butyl nitroxide (DTBN) and (O3S)2NO2–(Fremy's salt) are compared. The former is very sensitive, especially towards protic solvents whilst the latter is remarkably insensitive. Similarly, the electronic spectrum for DTBN is very solvent dependent whereas that for Fremy's salt is insensitive to solvent. We have previously established that DTBN forms two hydrogen bonds between the N—O group and water, but only ca. one to alcohols. We conclude that the N—O group for Fremy's salt does not readily form hydrogen bonds, all the solvation being at the two —SO–3 groups. However, in aqueous solutions one weak H-bond may be formed.