A highly porous copper metal-organic framework, [Cu 3 (BTC) 2 ] (BTC = benzene-1,3,5-tricarboxylate) was synthesized and used as a precursor for the synthesis of copper nanoparticles (NPs) and characterized by several techniques, including XRD, SEM, TEM, EDX and BET measurements. The as-synthesized copper nanoparticles were immobilized onto activated charcoal (AC) by means of ultrasonication at room temperature without any pretreatment. The Cu NPs/AC was employed as a heterogeneous catalyst for the cross-coupling of diphenyl diselenide and boronic acids to form diphenyl selenides through SeÀSe bond activation under ligand-, base-, and additive-free conditions. The copper NPs/AC, which combines the architecture of MOFs and the high surface area of charcoal, could be an efficient heterogeneous catalytic system that is compatible with a variety of substituents on diphenyl selenides. Its promising catalytic activity relative to that of other homogeneous systems and low catalyst loading for the synthesis of unsymmetrical diaryl selenides is an important application in the area of nanocatalysis. The Cu NPs/AC catalyst, which exhibits excellent catalytic activity and remarkable tolerance to a wide variety of substituents, led to Se sp 3 -, sp 2 -, and sp-carbon bond formation by using DMSO as a solvent and atmospheric air as oxidant. This approach can also be extended to the preparation of unsymmetrical organotelluride derivatives.Copper catalysts for cross-coupling reactions are an intense field of research because they are cost-effective and hold promise for the replacement of expensive metal sources for industrial purposes. Over the past decade, the construction of carbonÀselenium bonds has been an intriguing topic for researchers and the number of related publications has increased exponentially to date, mainly owing to the important therapeutic characteristics of these bonds, such as their antimicrobial, antiviral, antitumor, and antioxidant properties. In addition, chalcogens are important constituents of functional groups in biomolecules (i.e., those associated with redox chemistry) in eukaryotic biochemistry.[1] Moreover, seleniumbased ionic liquids have proven to be efficient catalysts in reactions such as the carbonylation of aniline, oxidation of thiols, syntheses of octahydroacridines and thioacetals, and the Baylis-Hillman reaction of aldehydes and electron-deficient alkenes. [2][3][4][5][6][7] Over the past decade, extensive work has been devoted to developing new methodologies for the creation of bonds between sp 3 -, sp 2 -, sp-carbon atoms and organochalcogens, especially selenium-and tellurium-based compounds. To synthesize these moieties, a number of synthetic methods have been reported so far. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] Of these, two methods are generally used. These methods involve the use of diphenyl diselenide (telluride) as starting precursor owing to its stability in air, environmental friendliness, and commercial availability. Diphenyl diselenide can be reacted w...

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New functionalized CuO hollow nanospheres on acetylene black (CuO/AB) and on charcoal (CuO/C) have been found to be effective catalysts for C-S bond formation under microwave irradiation. CuO catalysts showed high catalytic activity with a wide variety of substituents which include electron-rich and electron-poor aryl iodides with thiophenols by the addition of two equivalents of K2CO3 as base in the absence of ligands.

Magnetite (Fe3O4) nanoparticles supported on charcoal, graphene, or SBA‐15 were prepared by a simple solid‐state grinding technique and subsequent thermal treatment. The Fe3O4 nanoparticles supported on activated charcoal exhibited high catalytic activity and furnished good yields of the alkynyl selenide product in the cross‐coupling reaction of diphenyl diselenide and alkynes through activation of C−H and Se−Se bonds under ecofriendly conditions, surpassing traditional copper‐based catalysts to effect the same organic transformation.

Metal-organic framework (MOF) are a kind of highly organized porous crystalline material that has attracted significant interest in several applications, including chemical sensors, organic-, photo-, and electrocatalysis, and energy and environmental applications. [1][2][3][4][5][6] Yaghi et al. are pioneers in the development of MOF-based porous materials using organic linkers and metal-oxide clusters as anchors to create open frameworks. [7] MOFs are readily manufactured by reacting metal ions or clusters with organic linkers in the presence of aqueous or organic solvents at certain temperatures, resulting in crystalline powders or granules. [8] The use of solvent is also playing an effective role in the synthesis of uniform MOFs in addition to other parameters. The solvent used in synthesis remains inside the pores of the collected crystalline framework. These holes may be cleaned out using a more volatile solvent and vacuum-aided desorption, leaving behind an enormous void pore volume. [8] These activated MOFs are calcined further to operate for target-specific analyte adsorption and applications. By varying the chemical compositions of metal and organic linkers, a highly adaptable and adjustable porous architecture may be readily created. [9] MOFs may also provide different internal surfaces with distinct accessible metal sites, various structural topologies, and chemical variety, such as the usage of

An efficient method for copper nanoparticle catalyzed ligand-free S-C sp bond formation was developed by using dimethyl sulfoxide as the solvent, a base, and molecular oxygen as a green oxidant. This study provides a new catalytic route for the production of alkynyl sulfides through dual activation of S-S and C-H bonds. A wide range of alkynyl sulfides were synthesized on a large scale with a low catalyst loading (0.5 mol% Cu). This synthetic methodology could also be extended to selenides, whereas tellurides underwent analogous reactions in the absence of a catalyst.

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