Expanding the substrate scope in palladium-catalyzed C-N and C-C bond-forming reactions

摘要

Chapter 1. The first detailed study of the palladium-catalyzed amination of aryl nonaflates is reported. Use of bulky electron-rich monophosphinobiaryl ligands or BINAP allow for the catalytic amination of electron-rich and -neutral aryl nonaflates with both primary and secondary amines. Using XantPhos, the catalytic amination of a variety of functionalized aryl nonaflates resulted in excellent yields of anilines; even 2-carboxymethyl aryl nonaflate is effectively coupled with a primary alkyl amine. Moderate yields were obtained when coupling halo-aryl nonaflates with a variety of amines, where in most cases the aryl nonaflate reacted in preference to the aryl halide. Overall, aryl nonaflates are an effective alternative to aryl triflates in palladium-catalyzed C-N bond-forming processes due to their increased stability under the reaction conditions. Chapter 2. A catalyst comprised of a Pd precatalyst and 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl is explored in C-N bond-forming processes. This catalyst displayed unprecedented stability and scope allowing, for the first time, the coupling of substrates bearing a carboxylic acid or a primary amide.