Perchlorate Esters. 7. Solvolysis of 2-Adamantyl Perchlorate: Rate and Product Studies

Article abstract of DOI:10.1021/ja00322a026

The solvolysis of 2-adamantyl perchlorate proceeds at a convenient rate at temperatures close to ambient in a wide variety of pure and aqueous organic solvents.The nucleofugality of the perchlorate ion in S_N1 reactions is shown to be several orders of magnitude higher than for more conventional leaving groups, such as p-toluenesulfonate or bromide.Entropies of activation in pure organic solvents nd in 80percent ethanol are unusually high.Grunwald-Winstein plots are markedly curved, with deviations being especially marked for aqueous-acetone and aqueous-2,2,2-trifluoroethanol mixtures.A scale of Y_OClO3 values is developed and compared with scales for a variety of other leaving groups.In aqueous ethanol there is a preference for product formation by interaction with water molecules by a factor of ca. 1.7, essentially independent of solvent composition (96-50percent ethanol) and temperature.