Zinc Oxide Nanoparticles Catalysed One-Pot Three-Component Reaction: A Facile Synthesis of 4-Aryl-NH-1,2,3-Triazoles

Eco-Friendly Synthesis of 1H-benzo[d]imidazole Derivatives by ZnO NPs Characterization, DFT Studies, Antioxidant and Insilico Studies

Benzimidazoles are classified as a category of heterocyclic compounds. Molecules having benzimidazole motifs show promising utility in organic and scientific studies. A series of mono-substituted benzimidazoles were synthesized by ZnO-NPs via cyclocondensation between substituted aromatic aldehydes and o-phenylene diamine. The synthesized compounds were characterized and compared with the traditional methods. The nano-catalyzed method displayed a higher yield, shorter time and recyclable catalyst. The DFT study and antioxidant activity were investigated for benzo[d]imidazole derivatives. Compound 2a exhibited the highest antioxidant activity among the tested compounds. We focused on the catalytic activity of ZnO in the synthesis of heterocyclic structures with the goal of stimulating further progress in this field. The superiorities of this procedure are high yield of product, low amounts of catalyst and short reaction time.

Inorganic nanoparticles promoted synthesis of heterocycles

The application of inorganic nanoparticles as nanocatalyst for synthesizing of nitrogen containing heterocycles are reviewed. While an inclusive summary of the various catalysts utilized in the synthesis of heterocycles is demonstrated with limited focus on the preparation or characterization of the catalyst. The review is being summarized into different sections based on the size and the number of N-atoms in the cyclic compounds.

The Synthesis of Five-Membered N-Heterocycles by Cycloaddition of Nitroalkenes with (In)Organic Azides and Other 1,3-Dipoles

Cycloaddition reactions have emerged as rapid and powerful methods for constructing heterocycles and carbocycles. [3+2] Cyclo­additions of nitroalkenes with various 1,3-dipoles have been an interesting research area for many organic chemists. This review outlines the synthesis of N-substituted and NH-1,2,3-triazoles along with other five-membered N-heterocycles through cycloaddition reactions of nitro­alkenes.

1 Introduction

2 Synthesis of 1,2,3-Triazoles

2.1 Synthesis of NH-1,2,3-Triazoles

2.2 Synthesis of N-Substituted 1,2,3-Triazoles

3 Synthesis of Pyrrolidines and Pyrroles

4 Synthesis of Pyrazoles

5 Conclusion

Versatile precursor-dependent copper sulfide nanoparticles as a multifunctional catalyst for the photocatalytic removal of water pollutants and the synthesis of aromatic aldehydes and NH-triazoles

A series of copper sulfide (CS) nanoparticles (NPs) were synthesized just by varying the amount of the sulfur precursor and have been explored for the first time as a three-way heterogeneous catalyst in the photocatalytic oxidation of a number of aromatic alcohols, photocatalytic degradation and the reduction of water pollutants, and the facile synthesis of pharmaceutically important moiety 4-aryl-NH-1,2,3-triazoles. The green and novel protocol was successfully developed for the synthesis of covellite (CuS, Cu2+) and the covellite-villamaninite (CuS-CuS2) (copper in Cu2+, Cu1+) phases of copper sulfide, employing EDTA both as the chelating and capping agent via a simple precipitation method at room temperature using water as the solvent. A blue shift in the absorption spectra and band gap in the range of 2.02-2.07 eV prompted the investigation of the as-synthesized CS nanoparticles as the photocatalyst under visible light irradiation. In the absence of any oxidizing or reducing agent, covellite CuS nanoparticles showed the highest photocatalytic efficiency for the degradation of methylene blue (MB) and the reduction of carcinogenic and mutagenic Cr(vi) to non-toxic Cr(iii). Interestingly, the mixed phase of CS (CuS-CuS2), where Cu is present in both +1 and +2 oxidation states, was found to be the most efficient catalyst compared to CuS toward the visible light-mediated selective oxidation of various benzyl alcohols to their corresponding aldehydes. However, in the synthesis of substituted NH-1,2,3-triazoles, single-phase CS nanoparticles (i.e., CuS) provided the best catalytic result. This significant outcome certainly opens up the scope for realizing the present demand of low-cost multifunctional semiconductor nano-materials, which will have a huge impact on the economy and environment when they show more than two potential applications.

Metal-free syntheses of N-functionalized and NH-1,2,3-triazoles: an update on recent developments

An overview of the latest developments in the metal-free synthesis of non-benzo-fused N-functionalized and NH-1,2,3-triazoles is provided in this feature article. Synthetic studies that appeared from 2016 until August 2020 are organized according to a wide-ranging classification, comprising oxidative and eliminative azide-dipolarophile cycloadditions, diazo transfer reactions and N-tosylhydrazone-mediated syntheses. The newly developed methods constitute a significant contribution to the field of 1,2,3-triazole synthesis in terms of structural variation via either the exploration of novel reactions, or the exploitation of existing methodologies.

Designing a new basic ionic liquid [DHIM][OH] as a task specific bifunctional catalyst for facile microwave assisted metal free synthesis of 5-amino-1,2,3-triazoles

A green protocol for the synthesis of a series of 5-amino-1,2,3-triazoles from benzyl cyanide and phenyl azide derivatives catalyzed by the novel bifunctional ionic liquid [DHIM][OH] under microwave irradiation has been developed.