Neighboring-group effects in the reactivities of hydroxyl groups in D-glucopyranosides
1972
Roberts, E.J. | Wade, C.P. | Rowland, S.P.
Glucosides having the hydroxyl groups at C-2 and C-3 individually substituted were treated with N,N-diethylaziridinium chloride in the presence of concentrations of sodium hydroxide ranging from 0.1m to 6.0m. Substitution of the hydroxyl group at C-2 greatly enhances the reactivities of the hydroxyl groups at C-3 and C-4 in dilute base but has less effect in more-concentrated base. Substitution of the hydroxyl group at C-2 has little effect upon the reactivity of the hydroxyl group at C-6. Substitution of the hydroxyl group at C-3 depresses the reactivity of the hydroxyl group at C-2 throughout the range of base concentrations, but this substitution enhances the reactivity of the hydroxyl group at C-6 to a great extent in dilute base and to a much smaller extent in the more concentrated base. Proposed explanations for these results are discussed.
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