A General and Efficient Copper Catalyst for the Amidation of Aryl Halides

Abstract
An experimentally simple and inexpensive catalyst system was developed for the amidation of aryl halides by using 0.2−10 mol % of CuI, 5−20 mol % of a 1,2-diamine ligand, and K3PO4, K2CO3, or Cs2CO3 as base. Catalyst systems based on N,N-dimethylethylenediamine or trans-N,N-dimethyl-1,2-cyclohexanediamine were found to be the most active even though several other 1,2-diamine ligands could be used in the easiest cases. Aryl iodides, bromides, and in some cases even aryl chlorides can be efficiently amidated. A variety of functional groups are tolerated in the reaction, including many that are not compatible with Pd-catalyzed amidation or amination methodology.