CuCl2/[hmim]Br: A new recyclable catalytic system for aromatization of cyclic dienes

The combination of copper(II) chloride and 1-hexyl-3-methylimidazolium bromide ([hmim]Br) as a new recyclable catalytic system in the presence of TBHP for aromatization of cyclic dienes is disclosed. The system could furnish the corresponding aromatics in moderate to excellent yield. The competition between aromatization and oxidation of benzylic substrates were also studied. This developed catalytic system could be reused and recycled at least nine times without significant loss of the producitivity.