Metal - Palladium - Catalyzed Carbon - Carbon Coupling Reaction

In the field of organic chemistry, the formation of C-C is an important content of organic synthesis, while the nano transition-metal-catalyzed cross-couplings are the effective measures of the formation of C-C. In the basement of classical C-C cross-couplings, we keep looking for new catalysts and optimizing reaction systems in order to make traditional C-C cross-couplings to achieve better effect. In this article, a new, magnetic Pd/Fe3O4/s-G-catalyzed one-pot diazotization/cross-coupling of anilines and arylboronic acids has been developed. Through the on-going optimation of our reaction, we at last choose tBuONO as diazo reagent and BF3-Et2O as the additive. The experiments are conducted in MeOH at sixty degrees celsius and the reaction time is five hours. This process complemented the traditional Suzuki cross-couplings and provided a more economic approach for the preparation of biaryl products. At the same time, we have also studied the cycle test of our new catalyst. It turned out that this kind of catalyst can be reused four times and the effect is largely unchanged. The recycling of the catalyst is very convenient through magnetic separation.In recent years, the activation of inact C-H has been the research focus of organic chemistry. Although there has been great progress on the activation of C-H around the world, we still face huge challenges in transforming C-H to C-C, C-X, C-N, C-O, C-S directly. There is only one case of Pd-catalyzed reactions about the activation of C-H with acetyl as the directing group though a lot of functional groups have been used in directed C-H activation. In this article, Pd(OAc)2and Cu(OAc)2·H2O are served as the catalyst and oxidant separately. We use aromatic ketone derivatives and olefins as our reaction substrates and achieve the ortho-activation of sp2C-H and oxidative Heck reaction smoothly. This is a new development of directed and oxidative functionalization of C-H.