Highly Efficient MOF-Driven Silver Subnanometer Clusters for the Catalytic Buchner Ring Expansion Reaction

Abstract

The preparation of novel efficient catalysts—that could be applicable in industrially important chemical processes—has attracted great interest. Small subnanometer metal clusters can exhibit outstanding catalytic capabilities, and thus, research efforts have been devoted, recently, to synthesize novel catalysts bearing such active sites. Here, we report the gram-scale preparation of Ag 2 0 subnanometer clusters within the channels of a highly crystalline three-dimensional anionic metal–organic framework, with the formula [Ag 2 0 ]@Ag I 2 Na I 2 {Ni II 4 [Cu II 2 (Me 3 mpba) 2 ] 3 }·48H 2 O [Me 3 mpba 4– = N,N ′-2,4,6-trimethyl-1,3-phenylenebis(oxamate)]. The resulting crystalline solid catalyst—fully characterized with the help of single-crystal X-ray diffraction—exhibits high catalytic activity for the catalytic Buchner ring expansion reaction.

MOF-Triggered Synthesis of Subnanometer Ag02 Clusters and Fe3+ Single Atoms: Heterogenization Led to Efficient and Synergetic One-Pot Catalytic Reactions

“…After reduction, peaks at 368.9 and 374.7 eV can be observed (Figure S9b left), which are attributed to reduced Ag 0 atoms and confirm the full reduction of Ag + atoms after reacting with NaBH 4 . This point contrasts with that observed for the previously reported homometallic Ag 0 2 @MOF, 49 where only 50% of Ag + cations (those located in larger channels) were reduced by NaBH 4 forming Ag 0 2 nanoclusters, which could be explained by the higher content of Ag + present in the previously reported MOF. On the other hand, the analysis of the iron bands before and after introduction of NaBH 4 allows confirming that Fe 3+ cations neither are reduced by NaBH 4 nor reoxidized upon exposure to air.…”

Metal–organic frameworks as chemical nanoreactors for the preparation of catalytically active metal compounds

“…Again, the anionic charge of the framework was crucial to limit the number of inserted silver( i ) cations. 102 Remarkably, a close inspection of the crystal structures of the MOF with Pd II (Fig. 7b) and Ag I (Fig.…”

“…The same anionic CuNi MOF was later used following the same synthetic strategy for the in situ preparation of ligand-free Ag 0 2 SNMCs 102 (Fig. 6d–f), the whole formation process being also followed by SCXRD.…”

Covalent Organic Framework as a Metal-Free Photocatalyst for Dye Degradation and Radioactive Iodine Adsorption

“…The COF has shown the great capability to clean up volatile wastes like iodine with a very high degree of uptake capacity . The uptake proficiency is comparable to that of CSU-CPOPs-1 and CWNU-2NH 2 . Furthermore, C 6 -TRZ-TPA COF can capture 2-fold higher amount of iodine than LHCP-3 and NRPP-2 .…”

“…68 The uptake proficiency is comparable to that of CSU-CPOPs-1 69 and CWNU-2NH 2 . 70 Furthermore, C 6 -TRZ-TPA COF can capture 2-fold higher amount of iodine than LHCP-3 71 and NRPP-2. 72 A comparison has been made with other reported materials (Table S5, Supporting Information).…”