The photochemical nucleophile-olefin combination, aromatic substitution reaction: methanol-.alpha.- and .beta.-pinene, 1,4-dicyanobenzene. The photo-NOCAS reaction. Part 3
Medium- and Sensitizer-Dependent Radical Cation Reactions: Deprotonation in Fluid Solution and Solid Matrices.
作者:Heinz D. Roth、Hengxin Weng、Dahui Zhou、Prasad S. Lakkaraju、Antonio Sousa、Alexander D. Garnovskii、D. A. Garnovskii、Björn O. Roos、Claire Vallance、Bryan R. Wood
DOI:10.3891/acta.chem.scand.51-0626
日期:——
Radical cations generated by photo-induced electron transfer in solution or by chemical oxidation in the channels of a redox-active zeolite (NaZSM-5) may be di protonated, giving rise to neutral radicals. In solution, the germinate radical anion or an added nucleophile (methanol) may serve as the proton acceptor. Deprotonations in solution are not efficient: the corresponding products may be suppressed by several competing intra- or bi-molecular reactions. Although methanol serves as the base deprotonating at least one radical cation, it often is mort efficient as a nucleophile. thereby depressing deprotonation. Deprotonations in the zeolite are more effective, presumably, because competing reactions with outside reagents are precluded. Occasionally, NaZSM-5 zeolites promote complex reaction sequences, such as the conversion of p-propylanisole to the radical cation of anethole or the deprotonation-ring opening of 1,2-diphenylcyclopropane radical cation to exo,exo-diphenylallyl radical.
ARNOLD, DONALD R.;DU, XINYAO, J. AMER. CHEM. SOC., 111,(1989) N9, C. 7666-7667