Anchoring of palladium onto surface of porous metal-organic framework through post-synthesis modification and studies on Suzuki and Stille coupling reactions under heterogeneous condition.

An ecofriendly solid catalyst has been synthesized by anchoring palladium(II) into post synthetically modified metal organic framework IRMOF-3. The pore of IRMOF-3 was first modified with pyridine-2-aldehyde. The amine group of IRMOF-3 upon condensation with pyridine-2-aldehyde afforded a bidentate Schiff base moiety in the porous matrix. The Schiff base moieties were used to anchor palladium(II) ions. The prepared catalyst has been characterized by UV-vis, IR spectroscopy, X-ray powder diffraction, and nitrogen sorption measurements. Framework structure of the catalyst is not being destroyed in the multistep synthesis procedure as evidenced in X-ray powder diffraction studies. The catalyst has shown high activity toward the Suzuki and Stille cross-coupling reaction in 20% H2O/EtOH and EtOH medium, respectively, at 80 °C. The immobilized complex did not leach or decompose during the catalytic reactions, showing practical advantages over the homogeneous catalysis.