A convenient route to β-aryl-substituted cyclic enamines as key synthetic intermediates of sceletium and amaryllidaceae alkaloids

Abstract

Aryl groups were introduced into the position β to the nitrogen atom of cyclic amines by carrying out the anodic α-methoxylation of cyclic amine derivatives, the elimination of methanol from the oxidized products, the halomethoxylation of the resulting α,β-unsaturated cyclic amine derivatives, the replacement of the α-methoxy group with an aryl group, and the silver ion-promoted migration of the α-aryl group to the β-position, consecutively. This method was applied to the synthesis of some alkaloids such as (±)-mesembrine.