One-pot synthesis of bimetallic metal-organic frameworks (MOFs) as acid-base bifunctional catalysts for tandem reaction

Designing and preparing effective acid-base tandem catalysts is one of the research hotspots at present because assembling antagonistic active sites in one catalyst is still a challenge. In this work, amine-functionalized bimetallic metal-organic frameworks (MIL-101(Al/Fe)-NH2 (X)) were synthesized through a rapid reflux method and acted as acid-base bifunctional catalysts for tandem reaction (deacetalization-Knoevenagel condensation reaction). The bimetallic MOF catalysts exhibit enhanced catalytic activity when compared with monometallic catalysts either MIL-101(Al)-NH2 or MIL-101(Fe)-NH2. The superior performance of MIL-101(Al/Fe)-NH2 (X) has been attributed to the synergistic effect between Al3+ and Fe3+ ions and the hierarchical pore structure. Moreover, the as-synthesised samples showed robust stability, excellent recyclability, and durable catalytic activity.