Relative Reactivity of 1-Adamantyl Radicals toward Diphenylphosphide and Benzenethiolate Ions

Article abstract of DOI:10.1021/jo00387a009

Competition experiments of diphenylphosphide (Ph2P^-) and benzenethiolate (PhS^-) ions toward p-anisyl radicals gave a kP/kS ratio of 52 in liquid ammonia.In competition experiments between the same nucleophiles toward 1-adamantyl radicals, the kP/kS ratio could not be determined in liquid amonia (>1000).These competition experiments were also performed in Me2SO, and p-anisyl radicals gave then kP/kS ratio of 8.4 and 1-adamantyl radicals a kP/kS ratio of 830.This difference in selectivity is attributed to the greater stability of 1-adamantyl radicals compared to that of p-anisyl radicals.Competition experiment of 1-bromoadamantane and p-bromoanisole toward Ph2P^- ions gave almost the same reactivity (k(1-BrAd)/k(pBrAn)=0.96), suggesting that the radical anion intermediates in these reactions transfer their odd electrons to both substrates with similar rates.