Catalytic Friedel–Crafts Acylation and Benzoylation of Aromatic Compounds Using Activated Hematite as a Novel Heterogeneous Catalyst

Catalytic Friedel–Crafts acylation of benzene and unactivated benzenes such as chlorobenzene and nitrobenzene have been successfully carried out using activated hematite (α‐Fe 2 O 3 ) as a new, heterogeneous and green catalyst. Sonication of neat α‐Fe 2 O 3 in a water bath under air atmosphere at room temperature followed by heating at 200 °C, dramatically increase the activity of α‐Fe 2 O 3 . With the catalyst loading as low as 5.0 mol%, a wide variety of benzene derivatives were easily converted into the corresponding acylated products in a clean and high‐yielding acylation reaction. It was found that the activated α‐Fe 2 O 3 could be efficiently recycled and reused several times by simple washing with ethyl acetate, this cannot be attained with most of the traditional catalysts.