Combined directed Ortho metalation-cross coupling strategies. Design for natural product synthesis

Abstract

Recent efforts in our laboratories have established connections between the Directed ortho Metalation (DoM) (Scheme 1) and transition metal catalyzed cross coupling (Scheme 2) strategies. The combination of these with the Remote Metalation (Scheme 4) tactic has led to the evolution of powerful new methods for aromatic synthesis. The application of these concepts, singularly or combined, for the construction of alkaloids (Scheme 6), fluorenone natural products (Schemes 7, and 8), naphthobenzopyranones (Schemes 9 and 10), and naturally-occurring phenanthrenes is given as illustration of the new synthetic aromatic chemistry. © 1994 IUPAC