79831-48-4Relevant academic research and scientific papers
Radikale durch Oxidation von λ5-Phosphorin-Derivaten
Dimroth, Karl,Heide, Wilfried
, p. 3004 - 3018 (2007/10/02)
λ5-Phosphorins 1 with exocyclic OCH3-substituents are oxidized electrolytically or by oxidants first to the less stable cation radicals 2 and then by CH3+-splitting into the very stable neutral radicals 3. λ5-Phosphorins with F or N(CH3)2 at the P-atom give immediately the neutral radicals 7 and 13, resp.In the presence of fluorine ions 1,1-difluoro-λ5-phosphorin 5a is oxidized to the cation radical 6a which by water affords the neutral radical 7a.The small αP of the ESR spectra prove that the cation- and the neutral radicals are cyclohexadienyl radicals.The P-atom is not involved in the delocalization of the unpaired electron.By synthesis of the C-2/6 or C-4 13C-labelled 2,4,6-tri-tert-butyl-1,1-dimethoxy-λ5-phosphorin (1c), the 13C-coupling constants of the generated radicals (2c and 3c) could be measured and compared with those of known iso- and heterocyclic cyclohexadienyl radicals.
