Amino Acids To Promote Copper (i)-catalyzed Ullmann Reaction

S-aryl sulfides, N-aryl amines, N-aryl pyrroles, N-aryl indoles, N-aryl imidazoles, and N-aryl pyrazoles are prevalent in compounds that are of biological, pharmaceutical and materials interest.Copper-catalyzed Ullmann type reactions are traditional methods to assemble these compounds. However, the harsh reaction conditions (high temperatures, strong bases, stoichiometric amounts of copper or copper salts, long reaction times) are needed to effect these transformations. These procedures usually gave moderate yields.In order to overcome these drawbacks, our group, based on the previous work about the coupling reaction of aryl halides with a-amino acids, got the conclusion that amino acids could be used as additives to promote Ullmann-type reactions. Therefore, after optimization of reaction conditions such as solvents, temperatures, bases, ligands, copper reagents, the ratio of copper reagents and ligands etc., we found an effective catalytic system: 20 mol% N-methylglycine, L-proline or N,N-dimethylglycine/10 mol% Cul. In this thesis, we wish to describe the aryl C-N or C-S formation under the action of these catalytic systems.In the first chapter, we investigated the coupling of aryl iodides with thiols and found that under catalysis of CuI/L-proline both electron-rich and electron-poor aryl iodides could react with phenyl thiol to give the corresponding coupling products in good to excellent yields. However, good yields were only seen when electron-poor aryl iodides coupled aliphatic thiols.In the second chapter, we studied the coupling reaction of aryl halides with amines. CuI-catalyzed coupling reaction of electron-deficient aryl iodides with aliphatic primary amines completes at 40 °C under the promotion of N-methylglycine. Using L-proline as the promoter, coupling reaction of aryl iodides or aryl bromides...