Application of a new porous bimetallic H-bond catalyst in the preparation of biological henna-based pyrazolo[3,4-b]quinolines via a cooperative vinylogous anomeric based oxidation

Bimetallic organic frameworks (bimetallic-MOFs) are considered promising catalysts due to their tunable pores, strength, and high catalytic performance. Here, a bimetallic-MOF-based on iron (Fe) and cobalt (Co) metals was designed, synthesized and characterized. Next, the synthesized bimetallic-MOFs were post-modified with phenyl isocyanate to create urea moieties that are susceptible to hydrogen bonding (H-bond) catalytic activities. Various techniques such as SEM, XRD, BET/BJH, FT-IR, TGA/DTA, EDX and elemental-mapping were used to approve the structure of the synthesized catalyst. MIL-88B(Fe₂/Co)-UR acts as an H-bond catalyst in the multi-component reaction to form pyrazolo[3,4-b]quinolines via appropriate sections with medicinal properties. The features of using MIL-88B(Fe₂/Co)-UR as an H-bond catalyst are increased efficiency, decreased reaction time and reusability of the catalyst.