An Amine Functionalized Metal–Organic Framework as an Effective Catalyst for Conversion of CO₂ and Biginelli Reactions

Abstract

A highly porous and thermally stable anionic Zn(II)-framework, {[(CH)NH][Zn((μ-O))(L)(HO)]·4DMF·2HO} (1), having exposed metal sites and pendant amine groups has been synthesized adopting the solvothermal technique. This anionic 3D framework showed two-fold interpenetration with 45.1% void volume. It has a 3,6-c binodal net with rare sit 3,6-conn topology. The metal bound aqua ligand could be easily removed along with the guest molecules in the lattice upon activation to afford the desolvated framework 1'. This produced exposed metal sites that, along with the pendant amine groups incorporated in the ligand, generated a coordination space in the framework to make it an outstanding heterogeneous catalyst for the chemical fixation of CO with various epoxides under atmospheric pressure and in the three-component Biginelli reaction with different aldehydes, ethyl acetoacetate, and urea to afford dihydropyrimidinones.

Polyoxometalate-Based Metal-Organic Framework Fractal Crystals

“…37 However, involving bulky reactants and products, the mass transportation limitation caused by the microporous skeletons of MOFs inhibit their catalytic performance, despite the abundant Lewis (L) and Brønsted (B) acid catalytic sites. 38,39 We propose that the double hierarchical structures (pore and surface) of FcNENU-3a-4 would provide large mass transportation channels and enhanced accessibility to active acid sites, which is conducive to improving the catalytic performance in the case of bulky reactants or products. To this end, we explored the catalytic activity of FcNENU-3a-4 for the Biginelli reactions (Figure 4).…”

Geometry Mismatch and Reticular Chemistry: Strategies To Assemble Metal–Organic Frameworks with Non-default Topologies

“…Another MOF based on different carboxylate twists induced by the use of btb ligand with steric hindrance is MOF-156-J, which exhibits the rtl topology (Figure 13c). 141 In addition to modifying the level of twisting in the ligand carboxylates, other methods to confer systems with geometry mismatch might include altering either the ligand length 144,145 or the angle between the ligand branches 146 (i.e. using non-equilateral ligands).…”

Recent Advances in Homogeneous and Heterogeneous Catalyst in Biginelli Reaction from 2015‐19: A Concise Review

“…The lignad is H 3 L and its structure is shown in the Figure . The catalyst showed good to excellent yield of product towards the synthesis of DHPMs . The reaction performed with aldehydes (1 mmol), 3 (1.5 mmol) and 5 (2 mmol) at 60 °C and 2 h of reaction time in solvent‐free conditions.…”