Green synthesis of bis(indolyl)methane scaffolds as valuable biological materials catalyzed by Fe3O4/SiO2/PPA as a magnetic nanocatalyst

This study applied Fe3O4/SiO2/PPA magnetic nanocatalyst as a solid acid catalyst to produce bis(indolyl)methane derivatives (BIMs) under solvent-free conditions and at 50Oc. FTIR, XRD, EDX, FESEM, HRTEM, and BET were used for structure confirmation. The catalyst was environmentally friendly, heterogeneous, and recyclable without loss of catalytic activity. Also, this catalyst had high efficiency for the synthesis of bis(indolyl) methanes and the reaction products were obtained quickly. The synthesis of bis(indolyl)methanes from the reaction between indole derivatives and aldehydes has been carried out in short reaction times (5-30 min) with good to excellent yields (65-96%) using 50 mg of magnetic nanocatalyst at solvent-free conditions.