Abstract: The solvolysis of six trisubstituted haloallenes is reported. The solvent dependence and the activation parameters are found to be typical of SN1 reactions. The data are interpreted in terms of a unimolecular reaction proceeding via a charge-delocalized allenyl cation. Substitution of tert-butyl groups at the propargylic position of the cation encourages reaction at the allenyl position. The change in relative rate for phenyl substitution is ...
