New Methods for the Synthesis of Naphthyl Amines; Application to the Synthesis of Dihydrosanguinarine (IXa), Sanguinarine (X), Oxysanguinarine (IXb) and (.+-.)-Maclekarpines B (XI) and C (XII).

Natural products (IX)-(XII) are synthesized from the common precursor (VIII), which requires the change of the general procedure to the use of ZnCl2 as a catalyst because the more vigorous acetic acidic method leads to the products in significantly lower yield.