Synthesis of chalcones via Claisen–Schmidt condensation reaction catalyzed by acyclic acidic ionic liquids

Some recyclable acyclic SO3H-functionalized ionic liquids have been used as catalysts for the synthesis of chalcones by Claisen–Schmidt condensation. The chalcones could simply be separated from the catalyst by decantation. After removal of the water from the reaction mixture the catalysts could be recycled and reused for several times without noticeably decreasing the catalytic activity.