Solvothermal Synthesis of CuFe2O4@rGO: Efficient Catalyst for C-O Cross Coupling and N-arylation Reaction under Ligand-Free Condition

摘要

In this paper, we report copper ferrite supported reduced graphene oxide (CuFe2O4@rGO) synthesis by solvothermal process. The prepared CuFe2O4@rGO catalyst was used for C-O and C-N cross coupling reactions. The activity of the catalyst was compared with commercial Cu2O, CuOand CuFe2O4 for C-O cross coupling of iodobenzene with phenol. CuFe2O4@rGO was the best catalyst with 97% conversion towards iodobenzene at 100℃ under ligand free condition which is otherwise normally used. The virgin and five times reused CuFe2O4@rGO catalyst was characterized by XRD, SEM, FTIR, TEM, N2-adsorption desorption isotherm, XPS and TGA analysis. The effect of solvent, nature of base, speed of agitation, mole ratio, catalyst loading and temperature was studied for phenol and iodobenzene reaction and its activity was further explored in N-arylation of indole with idobenzene. The best conversion and yield were achieved at 100℃ at 1310~(-3) g/cm~3 catalyst loading. Notably, CuFe2O4@rGO was reusable without any loss of catalytic activity for five recycles. Reaction mechanism and kinetics are also presented. The overall process is novel and green.