Palladium And Rhodium Catalyzed New Reactions For CC Bond Construction

C-C bondsconstitute the skeleton of organic compounds, which determines their structure and properties. In the field of organic chemistry and catalysis, research to develop new methods for C-C bond formation occupies an important position. In particular, the construction of C-C bonds through Pd and Rh catalysis has become an important tool for organic synthesis. However, it is still a challenge to access structurally novel molecules under mild conditions even with the aid of these catalysts. The content of this thesis includes palladium catalyzed carbonylation of halogenated aromatics for the formation of aryl anhydride, acylation of indoles with olefins via C-H activation and rhodium catalyzed a-methylation of ketones using DMF as carbon source.(1) Palladium catalyzed carbonylation of aryl halides for the production of symmetrical aryl anhydridesPalladium catalyzed carbonylation reactions have been a versatile tool to producing carboxylic acid derivatives. However, there was only one report in the literature on the formation of acid anhydrides. We have developed a Pd catalyzed carbonylation of aryl iodides to produce acid anhydrides under mild conditions. The key to realizing this reaction is the rigorous control of the amount of water in the reaction. Good yields and selectivities were obtained for a range of substrates.(2) Palladium catalyzed oxidative Heck reaction of indoleswith electronic rich olefins3-Acetyl indoles have found various applications in medicinal chemistry and natural products synthesis. A new catalytic method for the synthesis of3-acetyl indoles is presented in Chapter2. The system uses palladium trifluoroacetate as catalyst andcopper acetate as oxidant, with water as additive, which allows for the oxidative Heck reaction of indoles with electronic rich olefins.(3) Rhodium catalyzed a-methylation of ketonesMethylation reactions are important for organic synthesis as well as biologic studies. In Chapter3, we describe the development of a novel catalytic system for the α-methylation of ketones. Various ketones could be methylated with the cheap N,N-dimethyl formanide(DMF) as the carbon source under rhodium catalysis. The method was successfully applied to the synthesis of a nature product, a3-methoxy estrone derivative.