Reductive Ullmann-Type Homocoupling of Aryl Halides Catalysed by Mixed Metal Oxide Nanocomposite (Pd/MnFe₂O₄) Under Aqueous Condition

A highly efficient magnetic nanocomposite, Pd/MnFe2O4 has been prepared by citrate gel auto combustion and deposition precipitation method for reductive Ullmann homocoupling of aryl halides in an aqueous medium. The physical and chemical properties of the synthesized composite were characterized by XRD, TEM, SEM, EDAX, VSM, and BET analysis. The synthesis of symmetrical biaryls has been achieved at admirable reaction conditions with high yield in a short reaction time. The nanocomposite catalyst could be easily separated by magnetic separation and recycled up to six reaction cycles with appreciable yields of desired products. The synthesized nanocomposite was found to be a best alternative catalyst for carbon-carbon bond formation in Ullmann-type homocoupling. [GRAPHICS]