Stereoselective Domino Rearrangement peri-Annulation of Cinchona Alkaloid Derivatives with 8-Bromo-1-naphthyl Grignard

Abstract

The unexpected domino coupling and rearrangement of the Cinchona alkaloid skeleton has been found to occur in the reaction of 9-chloro-9-deoxy-alkaloids with Grignards from peri -dihalogenonaphthalene. The cyclization and migration of the central quinuclidinylmethyl group (C9) from position C-4′ to position C-3′ of quinoline formed a novel chiral ring system of 5-aza-7 H -benzo[ no ]tetraphene, yielding products of unlike configuration. The proposed reaction pathway involves radical intermediates.