A CONVENIENT ROUTE TO BETA-ARYL-SUBSTITUTED CYCLIC ENAMINES AS KEY SYNTHETIC INTERMEDIATES OF SCELETIUM AND AMARYLLIDACEAE ALKALOIDS

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