Metal–organic frameworks constructed using acid–base mixed ligands, carboxylic acids and N-containing chalcone, and their catalytic performance for Knoevenagel condensation.

Using the mixed-ligand strategy, three metal–organic frameworks were constructed by virtue of the solvothermal reaction. These compounds exhibit similar two-dimensional layered structures and serve as an efficient and economical porous heterogeneous catalyst for Knoevenagel condensation under mild conditions. The yields of Knoevenagel condensation can be reached between 96% and 99% in the presence of catalysts 1–3. Notably, the catalytic performance of 1 through reusability was explored, and it was observed that 1 could be reused up to six cycles with almost consistent catalytic efficiency. [ABSTRACT FROM AUTHOR]