On the formation of Oxydimorphine (pseudomorphine, 2.2’-bimorphine)

In Beckurt’s test for alkaloids the substance for assay, generally a salt, is treated with a 0.1 N solution of potassium permanganate. In his study he used the hydrochloride of the alkaloid. In this communication the reactivity of both reagent and substrate have been checked and commented. The electron donor property of the phenol in morphine is enhanced by reaction with a weak base such as water. A phenoxy ion and a hydronium ion are formed. Resonance produces a carbanion at C-2 which transfers an electron to permanganate ion. This reduction to manganate is concomitant to oxidation of the organic molecule. The free radical thus formed is stabilized by electron coupling and 2,2’-bimorphine is obtained.