A mild and practical copper catalyzed amination of halothiophenes

We have found that N,N-dimethylethanolamine (deanol) is a useful solvent and ligand for copper catalyzed amination of a variety of unactivated and activated 2- or 3-halothiophenes. Primary amines, acyclic secondary amines, cyclic secondary amines and acyclic secondary amines with 2-hydroxyethyl functionality react with halothiophenes providing the corresponding aminated thiophenes in moderate to excellent yields. The mildly basic conditions utilized are compatible with many functional groups. The amination of halobithiophenes has also been examined. The aminothiophenes produced by this method are important intermediates in a variety of electronic and optoelectronic materials.