Amino Acids To Promote Copper-catalyzed Aryl Halide With Sodium Azide, Sodium, And Pinacol Borane Cross-coupling Reaction

The transition metal-catalyzed cross-coupling reactions to form sp~2 C-C or C-hetero atom bonds have received considerable attention in the past decades. In comparison with Pd and Ni, copper is a cheaper metal with lower-toxicity. In this dissertation we wish to report our recent investigations on the cross-coupling reactions of aryl halides with sodium azide, sodium sulfinate or pinacolborane under the catalysis of copper and amino acids.In the chapter 2 of this dissertation, we studied the cross-coupling reaction of aryl halides and vinyl iodides with sodium azide under the catalysis of copper and amino acids. Initially, we used the model reaction of 4-iodoanisole with sodium azide to explore the optimized conditions by varying solvents, additives, bases and copper source. It was found that the combination of CuI/Z-proline/NaOH as the catalytic system and DMSO as the solvent gave best coupling yield. Under these conditions several aryl iodides bearing a wide range of functional groups were converted into the corresponding aryl azides in good yields. Further studies indicated that for inactivated aryl bromides, switching the solvent to 7:3 ethanol/water provided best results. Furthermore, we also found that CuI/Z-proline sodium salt could catalyze the coupling of vinyl iodides with sodium azide to deliver the corresponding vinyl azides. The geometry of the C-C double bond was retained during the reaction course.In the chapter 3 of this dissertation, the cross-coupling reaction between aryl halides and sodium sulfinate under the catalysis of copper and amino acids was investigated. After screening solvents, ligands, copper source and reaction temperature, we found the optimized reaction conditions for this transformation was using CuI/Z,-proline sodium salt as the catalytic system and DMSO as the solvent. The reaction worked at 80℃ for aryl iodides, and 95℃ for aryl bromides. Both...