Metal−organic frameworks (MOFs) are extensively used in catalysis due to their robust structure, well-defined periodic reaction centers, and high porosity. We report Cu 3 (BTC) 2 •(H 2 O) 3 (HKUST-1) as an efficient heterogeneous catalyst for aziridination of alkene and ring-opening reaction of activated aziridines. Furthermore, we demonstrate that the transfer of a nitrogen group from PhINTs to olefins and its analogue to give aziridines takes place at the coordinatively unsaturated Cu(II) site of Cu 3 (BTC) 2 −MOF; however, the ring opening of activated aziridines is controlled by the Cu(II) Lewis acid site, and generation of coordinative unsaturation by thermal activation of the MOF is not necessarily important. The key advantage of this catalytic approach is the direct formation of C−C, C−N, C−O, and C−S bonds yielding β-aryl sulfonamide derivatives through a simultaneous aziridination ring-opening reaction of the alkene in one pot using a single catalyst.

Lead halide perovskite (LHP) based colloidal quantum dots (CQDs) have tremendous potential for photocatalysis due to their exceptional optical properties.

The coordinatively unsaturated sites (CUS) are vital in metal-centered catalysis. Metal–organic frameworks (MOFs) provide a unique opportunity to generate and stabilize CUS due to their robust structure. Generally, the generation of CUS in MOFs needs prior activation under heat and high vacuum to remove labile molecules occupying the catalytic sites. Herein, we report a solvothermal synthesis of a ready-to-use copper MOF containing accessible pre-existing CUS that does not need activation. The single crystal X-ray diffraction structure reveals a square planar Cu­(II) center with two N-methylimidazoles (Mim) and one benzenedicarboxylic acid (BDC) with the formula unit [CuII(BDC)­(Mim)2] n (Cu-1D) forming an infinite one-dimensional (1D) chain along the c axis. The 1D chains are stabilized by noncovalent π–π, CH···π, and H-bonding interaction to give 2D (sheet-like) and 3D networks in the solid state. The quantification of non-covalent interaction is studied by Hirshfeld surface analysis, and the formation of a higher architecture in the solid state is confirmed by SEM analysis. The reported Cu-1D MOF acts as a solid heterogeneous catalyst and exhibits efficient catalytic activity in intermolecular and intramolecular cross-coupling reactions. Intermolecular C-heteroatom cross-coupling of a variety of N-heterocycles, aliphatic, aromatic, alicyclic amines and amides (C–N), phenols (C–O), and thiols (C–S) with aryl halides (halide = I, Br) was achieved with 70 to 95% yield, better than the state-of-the-art Cu-based homogenous system. The C–N coupling catalytic cycle is initiated by the in situ reduction of Cu­(II) by KOH/DMSO to Cu­(I) species. Subsequently, Cu­(I) undergoes oxidative addition followed by reductive elimination to form a cross-coupled product. High stereoselectivity was found for the intramolecular C–N coupling reaction to give tetrahydroquinoxalines with an enantiomeric excess (ee) of more than 99%. For a broader application, Cu-1D was applied as the catalyst for the synthesis of a library of aziridines that gives yields of up to 99% with more than 93% recyclability for each cycle.

We report synthesis of highly stable CsPbBr3 QDs based photocatalysts using dibromoisocyanuric acid (DBI) as benign non-toxic bromide precursor. The QDs were applied as visible light photocatalyst for intramolecular cyclisation...

The sluggish oxygen reduction reaction (ORR) at the cathode is challenging and hinders the growth of hydrogen fuel cells. Concerning kinetic values, platinum is the best known catalyst for ORR; however, its less abundance, high cost, and corrosive nature warrant the development of low-cost catalysts. We report the hydrothermal synthesis of two novel Mn-based metal− organic frameworks (MOFs), [Mn 2 (DOT)(H 2 O) 2 ] n (Mn-SKU-1) and [Mn 2 (DOT) 2 (BPY) 2 (THF)] n (Mn-SKU-2) (DOT = 2,5dihydroxyterephthalate; BPY = 4,4′-bipyridine). Mn-SKU-1 contains dimeric Mn(II) centers where the two corner-shared MnO 6 octahedra fuse to give rise to an infinite Mn 2 O 10 cluster, whereas the two Mn(II) ions coordinate to DOT and BPY moieties to give rise to a pillared structure in Mn-SKU-2 and form a 3D → 3D homo-interpenetration MOF with a twofold interpenetrated net. The pyrolysis of as-synthesized Mn-MOFs at 600 °C under N 2 produced exclusively porous α-Mn 2 O 3 composites (PSKU-1 and PSKU-2), with the BET surface area of 90.8 (for PSKU-1) and 179.3 m 2 g −1 (for PSKU-2). These mesoporous MOF-derived α-Mn 2 O 3 composites were modified as cathode materials for the electrocatalytic reduction of oxygen. The onset potential for the oxygen reduction reaction was found to be 0.90 V for PSKU-1 and 0.93 V for PSKU-2 versus RHE in 0.1 M KOH solution, with the current density of 4.8 and 6.0 mA cm −2 , respectively, at 1600 rpm. Based on the RDE/RRDE results, the electrocatalytic oxygen reduction occurs majorly via the four-electron process. The electrocatalyst PSKU-2 is cheap, easy to use, retains 90% of its activity after 10 h of continuous use, and offers higher recyclability than Pt/C. The onset potential maximum current density and kinetic values (J k = 11.68 mA cm −2 and Tafel slope = 85.0 mV dec −1 ) obtained in this work are higher than the values reported for pure Mn 2 O 3 .