Solvent selective phenyl selenylation and phenyl tellurylation of aryl boronic acids catalyzed by Cu(II) grafted functionalized polystyrene

Recent Progress in Synthetic and Biological Application of Diorganyl Diselenides

Diorganyl diselenides have emerged as privileged structures because they are easy to prepare, have distinct reactivity, and have broad biological activity. They have also been used in the synthesis of natural products as an electrophile in the organoselenylation of aromatic systems and peptides, reductions of alkenes, and nucleophilic substitution. This review summarizes the advancements in methods for the transformations promoted by diorganyl diselenides in the main functions of organic chemistry. Parallel, it will also describe the main findings on pharmacology and toxicology of diorganyl diselenides, emphasizing anti-inflammatory, hypoglycemic, chemotherapeutic, and antimicrobial activities. Therefore, an examination detailing the reactivity and biological characteristics of diorganyl diselenides provides valuable insights for academic researchers and industrial professionals.

Latest developments on the synthesis of bioactive organotellurium scaffolds

This review deals with the latest developments on the synthesis of biologically promising organotellurim scaffolds reported during last two decades.

Transition-Metal-Free Synthesis of Unsymmetrical Diaryl Tellurides via SH2 Reaction of Aryl Radicals on Tellurium

Although diaryl tellurides are parent organotellurium compounds, their synthesis methods, especially for unsymmetrical ones, are limited. This may be due to the instability of diaryl tellurides and their synthesis intermediates under reaction conditions. Radical reactions are known to exhibit excellent functional group selectivity; therefore, we focused on a bimolecular homolytic substitution (S_H2) reaction between the aryl radical and diaryl ditelluride. Aryl radicals are generated from arylhydrazines in air and captured by diaryl ditellurides, resulting in a selective formation of unsymmetrical diaryl tellurides with high yields. The electronic effects of the substituents on both arylhydrazines and diaryl ditellurides on the S_H2 reaction of tellurium are also discussed in detail.

Recent Developments and Perspectives in the C-Se Cross Coupling Reactions

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The C-Se bond forming reactions are attractive synthetic strategies for biochemists and synthetic chemists alike for the synthesis of various molecules that are of biological, pharmaceutical and material interest. Therefore, the design and synthesis of organoselenium compounds currently constitute engaging fundamental problems in applied chemistry both in pharmaceutical and academic laboratories. This review discusses the recent works reported in carbon–selenium cross-coupling reactions with the emphasis on the mechanistic aspects of the reactions. The reacting species, the addition of ligands, selection of catalysts, use of suitable solvents, proper setting of reaction time, are well discussed to understand the detailed mechanism. Various simple, economical and environmentally friendly protocols are demonstrated, which ensured product stability, low toxicity, environmentally benign and excellent reactivity for the synthesis of organoselenium compounds. This review covers the scientific literature from 2010 to 2019.

Advances in Cu and Ni-catalyzed Chan–Lam-type coupling: synthesis of diarylchalcogenides, Ar2–X (X = S, Se, Te)

Advances in the Cu and Ni-catalyzed Chan–Lam-type coupling of aryl/heteroarylboronic acids with various chalcogen sources for diarylsulfide, diarylselenide and diaryltelluride synthesis are covered in this review.

Diaryl ethers synthesis: nano-catalysts in carbon-oxygen cross-coupling reactions

The diaryl ether moiety is not only prevalent in a significant number of natural products and synthetic pharmaceuticals but also widely found in many pesticides, polymers, and ligands. Ullmann-type cross-coupling reactions between phenols and aryl halides are regarded as one of the most important methods for the synthesis of this important and versatile structural motif. In recent years, the use of nano-sized metal catalysts in this coupling reaction has attracted a lot of attention because of these catalysts with their high surface-to-volume ratio, high surface energy, and reactive morphology allows for rapid C-O bond formation under mild and ligand-free conditions. In this review we will highlight the power of these catalysts in Ullmann-type C-O cross-coupling reactions.

Nanocatalysts for C–Se cross-coupling reactions

This mini review is an attempt to highlight the most important contributions toward the applications of nanocatalysts in carbon–selenium cross-coupling reactions with the emphasis on the mechanistic aspects of the reactions.

Synthesis of symmetrical and unsymmetrical tellurides via silver catalysis

The cross-coupling reaction of diaryl ditellurides with aryl boronic acids is described using AgNO₃ as a catalyst.

Acid-catalyzed oxidative cleavage of S–S and Se–Se bonds with DEAD: efficient access to sulfides and selenides

An acid/DEAD system for oxidative cleavage of S–S and Se–Se bonds to generate chalcogenium ions has been developed. These ions could be captured by nucleophile-tethered alkenes and nucleophilic aryl reagents such as arylboronic acids and arenes to give chalcogenides.

Cu(i)-Functionalized SBA-16: an efficient catalyst for the synthesis of α-ketoamides under moderate conditions

An efficient catalyst based on the cage-like mesoporous material SBA-16 as the support and Cu(i) as active sites has been successfully prepared. The catalyst demonstrated high catalytic activity (up to 88%) in the direct oxidative synthesis of α-ketoamides between acetophenone and piperidine, employing O2 from open air as the oxidant without other additives. A heterogeneous catalyst was applied in this reaction for the first time, and the catalyst could be easily separated from the reaction system by filtration and reused several times without a significant loss of activity.

CO2 fixation at atmospheric pressure: porous ZnSnO3 nanocrystals as a highly efficient catalyst for the synthesis of cyclic carbonates

Self-assembled, ultra small, porous zinc stannate nanocrystals have been synthesized, which catalyzes the formation of cyclic carbonates from various epoxide and CO₂ under very mild reaction conditions.

(2-Chlorobenzoyloxy)copper(i) catalyzed C–S cross-coupling of di(hetero)aryl disulfides with aryl boronic acids under base-free conditions

(2-Chlorobenzoyloxy)copper(i) exhibited high activity towards the challenging C–S cross-coupling of di(hetero)aryl disulfides with aryl boric acids with good to excellent yields under base-free conditions.