NUCLEOPHILIC REACTIONS OF EPOXY KETONES AMINOLYSIS OF SOME PARA-SUBSTITUTED EPOXY BENZALACETOPHENONES

The rates of the reaction of some p-substituted epoxy benzalacetophenones with piperidine have been measured at different temperatures. The reaction is unidirectional and gives the corresponding alpha -hydroxy- beta -piperidino- beta -phenyl propiophenones. Effect of the substituents has been analysed in terms of Hammett linear free energy relationship. The negative values of rho ** plus for the p-substituents (X) in the phenyl ring and the small positive values of rho **0 for the p-substituents in the benzoyl group are in accordance with the mechanism already proposed. The reaction has been interpreted in terms of a border line S//N2 mechanism.