The mechanism of the reaction of 2,3-dimethoxy-1,4-naphthoquinone with pyrrolidine in ethanol–water

Abstract

The reaction of 2,3-dimethoxy-1,4-naphthoquinone with pyrrolidine has been the object of a kinetic study in a wide range of ethanol–water solvent systems, at several temperatures. The effects of solvent composition and temperature have been discussed in terms of a mechanism with a tetrahedral intermediate. A change in the rate equation from first order in pyrrolidine at high water concentration of the solvent mixture to another more complex equation for lower water concentration has been found. Solvent effects are also discussed using the Koppel-Palm relationship.