Electron spin resonance study of free radicals generated from retinyl- and ionyl-derivatives.
Free radicals generated from alpha- and beta-ionyl bromides gave well resolved ESR spectra, but retinyl bromide and chloride gave only broad signals. Delocalised radicals were also spectroscopically observed on hydrogen abstraction from alpha-ionane, alpha-ionyltrimethylsilylether and buten-3-ynyl-2,6,6-trimethyl-2-cyclohexene. Retinyl and beta-ionyl radicals, derived from the corresponding xanthates, were successfully spin trapped with nitrosodurene. The results suggested that the secondary sites C(7) and C(9) were the most reactive in the beta-ionyl radical and that the secondary sites C(7) and C(11) and probably the primary site C(15) were the most reactive in the retinyl radical.
Mordi
R C
RC
Department of Chemistry, University of St Andrews, Fife, U.K.
Walton
J C
JC
D002084:Butylated Hydroxytoluene; D055598:Chemical Phenomena; D002621:Chemistry; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D010084:Oxidation-Reduction; D012172:Retinaldehyde / Q000031:analogs & derivatives*; D012176:Retinoids; D013859:Thiocarbamates
D005609:Free Radicals; D012176:Retinoids; D013859:Thiocarbamates; C008435:methyldithiocarbamate; D002084:Butylated Hydroxytoluene; D012172:Retinaldehyde