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چکیده
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Brønsted acidic ionic liquids have been of interest because they are capable to carry an acidic group such as SO3H. Immobilised acidic ionic liquids have been used as novel solid catalysts. Immobilized ILs combine the benefits of ILs and heterogeneous catalysts, such as high designability, ease of handling, separation, recycling and based on economic criteria, it is desirable to minimise the amount of ionic liquid utilised in a potential process.1-3 Xanthenes are usual natural products, significant matter and key-units in a diversity of biologically active and beneficial compounds. Due to their biological and pharmacological importance, several methods have been reported for the synthesis of xanthenes in the literature. The most common strategy for the synthesis involves condensation between aldehyde and active methylene compounds such as dimedone, cyclohexane-1, 3-dione catalyzed by number of Lewis acid catalysts.4,5 In this context, we have designed, synthesized and characterized novel ionic liquid-sulfonic acid functionalized silica-coated magnetic nanoparticle catalyst for synthesis aryl-1, 8-dioxo-octahydroxanthenes derivatives as a mild, recyclable, non-toxic and magnetic powerful solid acid catalyst under solvent-free conditions (Scheme 1). The scope and limitation of the described procedure will be discussed
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