GO-Fe3O4-Ti(IV) as an efficient magnetic catalyst for the synthesis of bis(indolyl)methanes and benzo[a]xanthen-11-one derivatives

In this study, a new and efficient magnetic composite was synthesized based on graphene oxide (GO). Initially, GO was coated with magnetite, and then Ti-(IV()) was fixed on GO-Fe3O4 via a covalent graft. The magnetic composite was characterized by FT-IR, EDS, XRD, FE-SEM, TEM, VSM and TGA techniques. It was designed as a compound with strong and recoverable catalytic properties. The prepared GO-Fe3O4-Ti-(IV) emerged to be of high catalytic activity for the synthesis of bis(indolyl)methane and benzo[a]xanthen-11-one derivatives under mild conditions. The stability and reusability of the catalyst were investigated too. All of the data proved that GO-Fe3O4-Ti-(IV) could be recycled five times without a marked loss of activity.