Regioselective synthesis of isoquinol(1,2-b)(3)benzazepines (homoprotoberberines) through 11-membered-ring stilbene lactams obtained by radical macrocyclization

The regioselective synthesis of isoquino(1,2-b)(3)benzazepines or homoprotoberberines using 11-membered stilbene lactams as key intermediates has been undertaken. The lactams were prepared by the intramolecular addition of an aryl radical to a trimethylsilylacetylene. The homoprotoberberines are formed when the amide of both lactams is reduced to an amide functionality and results in a regioselective (7,6)-transannular cyclization.