4 research outputs found
EPR study of pyrrolylâ1âoxyl and 3âpyrrolinylâ1âoxyl radicals
Pyrrolylâ1âoxyl, 3âphenylpyrrolylâ1âoxyl and a number of deuteriumâsubstituted derivatives were generated by hydrogen abstraction from the corresponding Nâhydroxypyrroles, and observed by EPR spectroscopy. They were all transient with lifetimes †10â2 s. The hyperfine splittings showed that unpaired spin was delocalized around the fiveâmembered ring with significant density at Nâ1, Câ3 and Câ4, but very low density at Câ2 and Câ5. NâHydroxpyrrole and pyrrolylâ1âoxyl were studied by the semiâempirical AM1 method, and the radical by the INDO method. The transient pyrrolinylâ1âoxyl was also generated from the corresponding Nâhydroxypyrroline and observed by EPR spectroscopy.</p