Direct Construction of Julolidines via Reductive Annulation of Quinolines and Conjugated Enones by a MOF-Derived Hierarchically Porous Iridium Catalyst

Abstract

Here, we describe the development of a MOF-derived hierarchically porous ZrO2-supported iridium catalyst (Ir-N@HP-mesoZrO2), featuring sufficient accessible catalytic sites even with ultralow iridium loading. Such a catalyst was successfully applied to selective and direct construction of julolidines via catalytic reductive annulation of readily available quinolines and conjugated enones, proceeding with good substrate and functional group compatibility, reusable catalyst, high step and atom efficiency, and easy applicability for the fabrication of functional molecules. The present work opens a door to further develop useful transformations by merging hydrogen transfer-mediated substrate activation with in situ incorporation of a coupling sequence under heterogeneous reductive catalysis.

Recent Advances in Hierarchical Porous Engineering of MOFs and Their Derived Materials for Catalytic and Battery: Methods and Application

“…[120] In many reported studies, hierarchical porous MOFs are synthesized firstly, and then they are converted into hierarchically porous carbon materials through a thermal conversion process (Figure 18a). [114,121] In addition, during the process of thermal conversion, MOFs usually inherit the microporous structure of the precursor, and sometimes generate some additional mesopores to form a hierarchical porous structure. [114,116,122] In the process of pyrolytic carbonization, the structure of pores can be controlled in many ways.…”

“…[114,121] In addition, during the process of thermal conversion, MOFs usually inherit the microporous structure of the precursor, and sometimes generate some additional mesopores to form a hierarchical porous structure. [114,116,122] In the process of pyrolytic carbonization, the structure of pores can be controlled in many ways. Such as adjusting the temperature and time of the pyrolysis process, which affects pore size and porosity.…”

“…Compared with solid materials, 3DOM porous structures not only greatly increases the specific surface area of catalysts to expose the active sites but also facilitates the diffusion of the reactants. Therefore, the regulation of [114] Copyright 2022, American Chemical Society. b) Na 2 SiO 3 as activator to fabricate the mesoporous carbon materials.…”

“…a) Schematic representation for Uio-66 derived hierarchical carbon-based catalysis materials. Reproduced with permission [114]. Copyright 2022, American Chemical Society.…”

Porous Organic Polymer Supported Nano Ruthenium Catalysts for Cascade Aromatization of Quinoxalin-2(1H)-one and C–H Annulation with Alkynes

“…In recent years, porous organic polymers supported metal catalysts served as a bridge between homogeneous and heterogeneous catalysis and have obtained more and more attention . Interestingly, such a strategy has the merits of a controllable coordination environment of metal with ligands, high specific surface areas and active metal centers, excellent stability, and easy recyclability . Furthermore, ruthenium nanocatalysts have been reported in diverse reactions, such as reduction, oxidation, Fischer–Tropsch, CO 2 transformation, and few C–H activations/deuterations .…”