Some unusual deuterium isotope effects—βversusγ—on the polarimetric rate of solvolysis of threo-1-methyl-2-phenylpropyl toluene-p-sulphonate

Abstract

Acetolysis, formolysis, and trifluoroacetolysis of (+)-threo-1-methyl-2-phenylpropyl toluene-p-sulphonate (I), and the deuteriated derivatives (II) and (III) gave isotope effects, k_I/k_IIversus k_I/k_III, of 1·073 versus 1·065, 1·160 versus 1·015, and 1·170 versus 1·009, respectively, which are not satisfactorily interpreted in terms of either a non-classical symmetrical phenonium ion or two rapidly equilibrating classical carbonium ions.