Thermally decomposed Cu–Fe-hydrotalcite: A novel highly active catalyst for o-arylation of naphthol and phenols by aryl halides

A novel, efficient and environmentally benign method has been reported for the synthesis of diaryl ethers by the o-arylation of napthol or phenols with aryl halides in dimethylformamide (as a solvent) under reflux, using a novel heterogeneous catalyst (having redox properties), obtained from thermal decomposition of Cu–Fe at 600 °C in the absence of externally added base. The catalyst comprises Cu(II) and Fe(III) species (oxides and hydroxides), which are uniformly distributed during the catalyst formation. The catalyst can be easily separated from the reaction mixture, simply by filtration and reused several times without a significant loss of its activity.

Graphical abstractCu–Fe-hydrotalcite decomposed at 600 °C is a novel, highly active, easily separable and reusable catalyst useful for the o-arylation of different phenols with aryl halides in DMF under reflux in a short reaction time.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Catalyst obtained from thermal decomposition of Cu-Fe-hydrotalcite at 600 °C. ► Catalyst comprises of uniformly distributed Cu(II) and Fe(III) species. ► High product yields in o-arylation of phenols with aryl halides. ► No requirement of externally added base. ► Environmentally more benign protocol for synthesis of diaryl ethers.