Metal-organic framework-118 (MOF-118): A heterogeneous catalyst for effective synthesis of pyrroles from aryl amines and 2,5-hexanedione

Metal-organic frameworks (MOFs) have been widely used in many applications, particularly catalysis. Here, we reported the synthesis and characteristics of metal–organic framework-118 (MOF-118), which was used for pyrroles synthesis via Paal-Knorr reaction between diketone and aryl amines. It was found that MOF-118 exhibited excellent activity in the reaction between p-anisidine and 2,5-hexanedione. The reaction parameters including catalyst concentrations, reaction temperatures, molar ratio of p-anisidine/2,5-hexadione, and solvents, were systematically investigated. Almost 100% conversion was achieved under the optimized reaction conditions. The reusability of MOF-118 catalyst was studied. Furthermore, we demonstrated that the functional groups on aryl amines have strongly effect on the reaction rate.