Post-synthetic modified MOF for Sonogashira cross-coupling and Knoevenagel condensation reactions

•Synthesis of azolium based MOF.•Design of efficient heterogeneous NHC catalyst.•Knoevenagel condensation reaction by NHC catalyst MOF.•The use of Pd(II)-NHC-MOF for Sonogashira cross-coupling.

A new heterogeneous NHC catalyst (1-Pd) was obtained by the post-synthetic modification of an azolium-containing metal-organic framework (1) which was synthesized by solvothermal reaction of 1,3-bis(4-carboxyphenyl)imidazolium chloride (H2L+Cl−) and Zn(NO3)2·6H2O. This new material, 1-Pd, was characterized by PXRD, TGA, SEM, TEM, 1H and 13C NMR, FTIR and XPS measurements. This catalyst exhibited an excellent activity for both Sonogashira cross-coupling and Knoevenagel condensation reaction retaining its catalytic and uniform distribution of the active sites, palladium (II) anchored on N-heterocyclic carbene (NHC-Pd(II)), for at least four cycles without losing its structural integrity.

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