Structural Design of Mn-Metal–Organic Frameworks toward Highly Efficient Solvent-Free Cycloaddition of CO₂

Abstract

Three new manganese-based metal−organic frame-, and [Mn 2 (L) 2 (DMF) 2 (H 2 O)]• 3DMF (3), have been synthesized with the ligand H 2 L (Nphenyl-N′-phenylbicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide dicarboxylic acid). The secondary building units (SBUs) of the Mn-MOFs are controlled by changing the anions of the manganese salts, and the structures are modified from two-fold interpenetrating to non-interpenetrating by adjusting the mixed solvent systems. Along with the structural modification of the Mn-MOFs, we optimized their catalytic activities for the reaction of CO 2 and epoxides toward cyclic carbonates. Both the activity and reusability of the Mn-MOFs are successfully improved in the solvent-free cycloaddition of CO 2 with various epoxides under the mild conditions of atmospheric pressure and 70 °C.

Hexagonal Layer Manganese Metal–Organic Framework for Photocatalytic CO2 Cycloaddition Reaction

“…For example, a series of structurally controlled Mn-MOFs for catalytic CO 2 cycloaddition reaction made from N -phenyl- N ′-phenylbicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide dicarboxylic acid showed high yields with different epoxides. 38 …”

CO2 fixation into cyclic carbonates catalyzed by single-site aprotic organocatalysts

“…17,18 The development of catalysts for the production of the title materials is currently a hot topic to overcome the stability and inertness of CO 2 and to diminish the activation energy barrier for such a reaction. 19 Such catalysts might be metal oxides, 20,21 salen-, 22,23 salophen-, 24 and porphyrin 25 based metal complexes, metal-organic frameworks, 26,27 and polyoxometalates. 28 In general, those catalytic systems are comprised of a Lewis acid and a nucleophilic co-catalyst under high or atmospheric pressure, 29,30 where the coordination of the epoxide oxygen to the Lewis acid site activates the epoxide ring-opening.…”

New Stable Cu–K Metal–Organic Framework Constructed by a Bifunctional Ligand: Structure, Application in Dye Adsorption, and Catalytic CO2 Cycloaddition Reaction

“…One of the most promising strategies is the cycloaddition reaction of CO 2 and epoxides to cyclic carbonates, as the whole reaction conforms to a 100% atomic economy . Also, the cyclic carbonates are important industrial raw materials with wide applications. − On the other hand, organic dyes, which are widely used in printing, textile, papermaking, and pharmaceutical industries, may cause serious water pollution problems. , Traditional methods of removing organic dyes from wastewater are usually accompanied by some inherent disadvantages, such as high cost, low efficiency, poor selectivity, and inability to recover adsorbents (may cause secondary pollution). , Therefore, it is necessary to develop new materials with a low price, recyclability, and high selectivity for adsorption and separation of organic dyes.…”