Fe3O4@SiO2/EDAC-Pd(0) as a novel and efficient inorganic/organic magnetic composite: sustainable catalyst for the benzylic C-H bond oxidation and reductive amination under mild conditions

A facile and novel methodology has been reported for the synthesis of Pd(0) nanoparticles onto ethylene diamine functionalized inorganic/organic magnetic composite [Fe3O4@SiO2/EDAC-Pd(0)]. The amine functionalized inorganic/organic substrate proved to be an efficient host for the immobilization of palladium nanoparticles giving a highly stable, water dispersible, active and yet magnetically recoverable heterogeneous catalyst. The synthesized catalyst displayed remarkable activity towards the selective C-H bond oxidation using TBHP and reductive amination of aldehydes with nitroarenes using atom efficient molecular hydrogen in green solvents, and could be reused efficiently upto 6 consecutive runs. The novel catalyst is characterized by FT-IR, TGA, XRD, SEM, HRTEM, EDX, ICP-AES, XPS and VSM techniques. Because of the magnetic nature of the catalyst, it can be retrieved using an external magnet, which eliminates the obligation of catalyst filtration after completion of the reaction, thus making it an eco-friendly and economical catalyst to perform the organic transformations.