Acid-Catalyzed Hydrolysis of Bridged Bi- and Tricyclic Compounds. XXXIII. Hydration of exo- and endo-5-Methoxy-2-norbornenes and 3-Methoxynortricyclane.
作者:Martti Lajunen、Jouni Jantunen、Päivi Koiranen、B. C. Hauback、Ola Persson、Ruo-Hua Zhang、Kurt V. Mikkelsen、Alexander Senning
DOI:10.3891/acta.chem.scand.52-0728
日期:——
The disappearance of exo- and endo-5-methoxy-2-norbornenes and 3-methoxynortricyclane in aqueous perchloric acid was followed by capillary GC at different temperatures and acid concentrations. The rate constants, activation parameters, solvent deuterium isotope effects, excess acidity plots and products accord with the rate-determining protonation of the double bond or the cyclopropane ring followed mainly by water attack on a methoxy-substituted 2-norbornyl cation (Ad(E)2 mechanism). The excess acidity plots were corrected according to a partial protonation of the ether oxygen atom. No significant cleavage of the ether linkage was observed.