Copper-based MetalOrganic Frameworks as Heterogeneous Catalysts for Cross-Dehydrogenative Coupling Reaction

In the present work, Cu-based metal-organic framework (MOF), Cu-BDC is synthesized, characterized by powder X-ray diffraction (XRD), infrared (IR) spectroscopy and scanning electron microscopic (SEM) techniques. After confirming the formation of Cu-based MOFs (Cu-BDC), the catalytic performance of Cu-BDC is studied in the cross dehydrogenative coupling between 2-oxindole and malononitrile using dimethylformamide (DMF) as solvent under air atmosphere at 80 degrees C to afford 98 % yield of the desired product. Further, catalyst reusability is also studied and observing no significant decrease up to third recycles. Cu-BDC is also active in promoting the coupling between 2-oxindole derivatives with malononitrile under identical conditions with higher yields of the expected product. A suitable mechanism is also proposed for this transformation. Copper-based metal organic framework (Cu-BDC) is reported as a reusable heterogeneous catalyst for the cross dehydrogenative coupling between 2-oxindole derivatives and malononitrile in dimethylformamide as solvent under air atmosphere at 80 degrees C to afford 79-98 % yields.image