[3+2]-Cycloaddition for Fully Decorated Vinyl-1,2,3-Triazoles: Design, Synthesis and Applications.

The small heterocyclic ring of the 1,2,3-triazole module is one of the most widely investigated compounds in numerous applications of biological, medicinal, pharmaceutical and materially important molecules. In this regard, a large number of synthetic methodologies and approaches have already been reported to construct such a heterocyclic core structure in a selective manner. However, the vinyl-substituted 1,2,3-triazole moiety is another privileged segment in heterocyclic chemistry. The selective introduction of simple vinyl and functionalized vinyl groups onto the three different positions of the 1,2,3-triazole framework can significantly improve the properties of the molecule. Accordingly, high-yielding efficient approaches for the selective construction of vinyl-containing 1,2,3-triazoles becomes a promising branch of chemistry among practitioners of industry and academia. In this minireview, we have discussed recent advances in the construction of highly selective three different vinyl-containing 1,2,3-triazoles. In addition, representative synthetic methodologies and approaches for the corresponding three different classes of vinyl-1,2,3-triazoles and their applications have been described as well in this review.