A study of diketopiperazines as electron-donor initiators in transition metal-free haloarene-arene coupling.

Several diketopiperazines have been shown to promote carbon-carbon coupling between benzene and aryl halides in the presence of potassium tert-butoxide and without the assistance of a transition metal catalyst. The structure of the diketopiperazine has an influence on its reductive potential and can help to promote the coupling of the more challenging aryl bromides with benzene.