The palladium-catalyzedα-arylation of actived-methylene compounds has become a useful and general synthetic method. In this process, an enolate generated from malonate/acetoacetate and corresponding base in the presence of a palladium catalyst couples with the aryl halide to giveα-arylated product. With the application of sterically hindered, electron-rich alkylphosphines, this reaction is now applicable to a broad range of aryl halides.In this thesis, we studied the palladium/ligand-catalyzedα-arylation reactions between malonate/acetoacetate and aryl halides with our newly designed monophosphine ligands in order to develop an efficientα-arylation reaction which can be employed in synthesis of some important intermediates and complex molecules. We studied the ligand effects, base effects, and Pd species effects in the Pd-catalyzed arylation of malonate and acetoacetate. We found that with 2-di-tert-butylphosphino-2-isopropoxy-1,1'-binaphthyl as ligand, palladium-catalyzed arylation malonate/acetoacetate with a variety of aryl halides proceed efficiently with K3PO4 and K2CO3 as base, respectively.
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