The Chemistry of Hager’s Test for Brucine

Abstract

The purpose of the article is clear up what is happening in the test tube during the Hager’s test for brucine, that is, throughout the interaction of brucine with manganese dioxide in acidic medium. The paper is a Theoretical Organic Chemistry Study based on the chemical deportment of reagent and substrate, in accordance with the reaction medium. A series of reactions occur during the test: electrophilic attack to double bond, acidolysis of organometallic intermediates, oxidation of secondary alcohol to ketone, acid catalysed hydration, reaction of enol, epoxide formation, ring opening, selective reaction of diol, and ring cleavage of seven-member ring. A yellowish-red to blood-red colour is observed after filtering residual black manganese dioxide. This is due to halochromism, present in acidic medium, since there are no chromogenic groupings.