A Domino Azidation/C-H Amination Approach toward Trifluoromethyl Substituted Imidazoles.

N-Alkyl enamines can be transformed into 2,4,5-trisubsituted imidazoles by reacting with (diacetoxyiodo)benzene and TMSN3 under the catalysis of a copper salt such as Cu(OAc)2. Tetrabutyl ammonium iodide was also capable of promoting the reaction. The transformation from N-alkyl enamines into 2,4,5-trisubsituted imidazoles took place in a domino azidation/intramolecular C(sp3)-H amination pattern. The present reaction provides a new efficient method for the preparation of 4-(trifluoromethyl) imidazoles.