Studies On The Palladium Catalyzed Synthesis Of Benzofurans And Indoles

This dissertation is divided into two parts, each consists of two chapters. Part I describes the studies on the synthesis of benzofurans and part II on the construction of indoles.The first chapter of part I gives a review to the studies on benzofurans and transition metals, such as Pd, Cu, Pt, Ru, Rh, and their cooperatively catalytical synthesis of benzofurans. It is stressed on the descriptions of palladium catalyzed allyl cyclization, palladium catalyzed Sonogashira coupling, palladium catalyzed carbonylization, cyclization of o-alkyne phenols, and other palladium catalyzed reactions leading to the formation of benzofurans. The second chapter shows the studying results for the synthesis of 2-aryl substituted benzofurans. Based on previous works, a new one-pot protocol to the synthesis of benzofurans was adopted in this paper. The reaction conditions were optimized. A series of 2-aryl substituted benzofurans were synthesized under the optimal reaction conditions. This one-pot process offers advantages like cheap reagents, easily handling, no need for intermeadite isolation, and operational simplicity. It can be used for the preparation of natural products.The first chapter of part II reviews the researches on the synthesis of indoles. Several approaches to the palladium catalyzed synthesis of indoles are: (1) cyclization of alkyne, (2) cyclization of alkene, (3) cyclization via intramolecular coupling of vinyl halides onto aromatic positions, (4) cyclization via intramolecular C-N bond forming reactions, and other transition metal catalyzed reactions. The second chapter gives applications of the one-pot protocol to the synthesis of 2-aryl benzofuran in the construction of indoles under optimal conditions, Indole products were obtained successfully.