Strategies Towards the Synthesis of N2-Substituted 1,2,3-Triazoles

Abstract

The chemistry of 1,2,3-triazoles gained much attention since the discovery of the copper catalyzed Alkyne-azide cycloaddition (CuAAC) reaction which delivers exclusively the 1,4-regioisomer in high yields. On the other hand there is still no universal methodology capable of delivering the N2 substituted regioisomer. The unique properties of these N2-substituted 1,2,3-triazoles have stimulated synthetic efforts on the developments of methodologies capable of delivering it in high yield and selectivity. These efforts are the subject of the presented review.

Triazole-Modified Peptidomimetics: An Opportunity for Drug Discovery and Development

“…Nevertheless, the thermal process is not regioselective and the result is the formation of both 1,4 and 1,5-disubstituted 1,2,3-triazoles (Akula and Lakshman, 2012 ). The reaction was performed between an acetylene and the azide under reflux conditions in toluene, leading to a mixture of 1,4 and 1,5-regioisomers of 1,2,3-triazoles (Souza and Miranda, 2019 ). In 2002, Meldal and Sharpless and their colleagues independently reported the most extensively used click chemistry method (Rostovtsev et al, 2002 ; Tornøe et al, 2002 ).…”

“…Thus, researchers are stimulated to design novel structures, making an effort to redeem these issues. The chemistry of peptides and heterocycles is challenging in this (Souza and Miranda, 2019).…”

“…Triazoles are five-membered aromatic heterocyclic moieties, which possess three nitrogen and two carbon atoms in the structure (Costa et al, 2017 ). They occur in two tautomeric forms: the 1,2,3-triazole or the 1,2,4-triazole ( Figure 1 ) depending on the position of the NH group in the ring (Souza and Miranda, 2019 ).…”

“…FIGURE 1 | Structures of the two isomeric forms of triazoles. (A) 1,2,3-triazole; (B) 1,2,4-triazole(Souza and Miranda, 2019).…”

Azoles for Renewable Energy Development and Wood Treatment

“…Generally, PEM are made of polymeric organic compounds containing acidic functions (example, Nafion). The restrictions of modern membranes have nurtured the research and development of alternative membranes, including doped polybenzimidazole (a combination of Nafion and metal oxides), organosiloxane based on inorganic-organic hybrids with various acidic species, and sulfonated polymers based on aromatic hydrocarbons [8][9][10][11][12][13][14].…”