CoII immobilized on an aminated magnetic metal-organic framework catalyzed C-N and C-S bond forming reactions: a journey for the mild and efficient synthesis of arylamines and arylsulfides

In this work, we report a simple and versatile method for the modification of a metal-organic framework (NH2-MIL53(Al)) in a step-wise manner. To characterize the synthesized nanostructured catalyst, a variety of spectroscopic and microscopic techniques including FT-IR, XRD, BET, TEM, FE-SEM, EDX, EDX-mapping, TGA, XPS, VSM, ICP-OES and CHN have been employed. Fe3O4@AMCA-MIL53(Al)-NH2-Co-II NPs, which benefit from small nanocrystalline size (10-30 nm, according to the XRD and TEM data) in combination with the coexistence of magnetic nanoparticles, a metal-organic framework, and cobalt species, were found to be an excellent environment catalyst to promote the C-N and C-S cross coupling reactions. A wide range of functional substrates including electron-withdrawing and electron-donating aryl halides underwent the coupling reaction with aromatic/heteroaromatic/benzylic and aliphatic amines and sulfides. The results demonstrated that the yields of the target products were good to excellent and the catalyst can be recycled for at least seven recycling runs without a discernible decrease in its catalytic activity. Furthermore, the heterogeneity studies (such as hot filtration and poisoning tests) efficiently confirmed that the as-synthesized nanostructured catalyst is heterogeneous and completely stable under the reaction conditions. We hope that our study inspires more interest in designing novel catalysts based on using low-cost metal ions (such as cobalt) in the field of cross coupling reactions.