Cluster-Based Bimetallic\n3d–4s {CuIn} Metal–Organic\nFramework for Efficiently Catalyzing Diazotization of Primary Amines

Organic azides are extensively utilized in organic synthesis\nand\nclinical drug development. However, the commonly employed catalysts\nfor the preparation of organic azides, such as inorganic salts and\nsimple metal complexes, often suffer from low yields and the production\nof byproducts. In this study, we report the rational synthesis of\na porous, cluster-based bimetallic metal–organic framework\n(MOF) with a large nanocage of 1 nm in diameter, termed compound <b>1</b>, designed for this specific reaction. Compound <b>1</b> exhibits exceptional solvent stability, remaining stable even in\nthe presence of corrosive triethylamine. Catalytic investigations\nrevealed that compound <b>1</b> serves as an effective catalyst\nfor the reaction of primary amines with TfN<sub>3</sub>, yielding\nvarious organic azides under mild conditions. Moreover, this MOF catalyst\ndemonstrates significant catalytic activity for the aminoglycoside\ndrug kanamycin A. The reaction proceeds smoothly with compound <b>1</b>, producing fewer byproducts and exhibiting good regioselectivity.\nAdditionally, the catalyst can be reused at least five times without\na noticeable decrease in catalytic activity. Notably, this represents\nthe first application of MOF materials in the amino diazotization\nreaction.