Multicomponent synthesis of 1-aryl 1,2,4-triazoles

Strategies for synthesis of 1,2,4-triazole-containing scaffolds using 3-amino-1,2,4-triazole

1,2,4-Triazole-containing scaffolds are unique heterocyclic compounds present in an array of pharmaceuticals and biologically important compounds used in the drug-discovery studies against cancer cells, microbes, and various types of disease in the human body. This review article summarizes the pharmacological significance of the 1,2,4-triazole-containing scaffolds and highlights the latest strategies for the synthesis of these privileged scaffolds using 3-amino-1,2,4-triazole. This review stimulates further research to find new and efficient methodologies for accessing new 1,2,4-triazole-containing scaffolds which would be very useful for the discover of new drug candidates.

Intramolecular oxidative cyclization of N-(2,2,2-trifluoro-1-(phenylimino)ethyl)benzimidamide

A fast and convenient method for synthesis of 1,3-diaryl-5-(trifluoromethyl)-1H-1,2,4-triazole compounds has been described via intramolecular oxidative cyclization of the N-(2,2,2-trifluoro-1-(arylimino)ethyl)benzimidamide intermediates by I₂/KI in excellent yields without any purification. N-(2,2,2-Trifluoro-1-(arylimino)ethyl)benzimidamide intermediates which are used in this project have been synthesized from the reaction of N-aryl-2,2,2-trifluoroacetimidoyl chlorides and benzamide hydrochloride derivatives at room temperature for the first time.

A Multicomponent Electrosynthesis of 1,5-Disubstituted and 1-Aryl 1,2,4-Triazoles

A novel electrochemical route has been developed for the synthesis of 1,5-disubstituted and 1-aryl 1,2,4-triazoles from aryl hydrazines, paraformaldehyde, NH₄OAc, and alcohols. In this multicomponent reaction system, alcohols act as solvents as well as reactants and NH₄OAc is used as the nitrogen source. With the assistance of reactive iodide radical or I₂ and NH₃ electrogenerated in situ, this process could effectively avoid the use of strong oxidants and transition-metal catalysts and be smoothly carried out at room temperature to give a wide array of 1,2,4-triazole derivatives in good to high yields. Preliminary studies reveal that the reaction mechanism involves a radical process.

[3 + 2] Cycloaddition of Nitrile Ylides with Diazonium Salts: Copper-Catalyzed One-Pot Synthesis of Fully Substituted 1,2,4-Triazoles

A novel [3 + 2] cycloaddition between nitrile ylides and diazonium salts was well-established. This copper-catalyzed three-component reaction was distinguished by mild conditions, ready availability, and operational simplicity, thus opening access to 1,2,4-triazoles with a diverse set of substitution patterns.