Pyrazole-functionalized Zr-MOF and membrane as efficient and recyclable catalyst for multi-component Hantzsch condensation reaction

• Cost-effective, robust, pyrazole-functionalized DUT-67-PZDC MOF have been demonstrated for the Hantzsch reaction • Excellent yield of substrates was demonstrated with a wide substrate scope. • Catalyst displayed high Turnover numbers and Turnover frequency • Easy processability of the catalyst to the membrane for facile recovery and recyclability was confirmed • The catalyst can perform multi-fold Hantzsch reaction Dihydropyridines, owing to their diverse biological activities, are an important class of heterocyclic scaffolds in pharmaceutical chemistry. Commonly used methodology for the synthesis of DHPs is the Hantzsch Condensation reaction in the presence of a catalyst. Herein, we present a pyrazole-functionalized robust Zr-Metal Organic Framework, DUT-67-PZDC, and its membrane for tandem Hantzsch Condensation reaction. The presence of pyrazole moieties introduces Lewis basic sites, while the Zr cluster serves as Lewis acidic sites, facilitating the multicomponent condensation of aldehydes, β-ketoesters, and ammonium acetate under mild conditions, affording the corresponding 1,4-dihydropyridine derivatives with excellent yields (≥90%), Turnover number (∼55-102) and turnover frequency (8.7-17 h -1 ). Notably, MOF-derived self-standing membrane exhibits similar activity while improving the catalyst recovery. Both powder and membrane forms of DUT-67-PZDC demonstrate high stability and retain catalytic performance over multiple reaction cycles, ensuring their recyclability. This catalyst not only provides a broad substrate scope but also facilitates a multifold Hantzsch Condensation reaction.