Advances in the synthesis of symmetric 1,3,5-triazines: catalysis and mechanistic pathways

Abstract

Triazines are nitrogen-containing heterocycles with a variety of applications as building blocks or catalysts in organic synthesis, materials science, analytical chemistry, and pharmaceuticals. 1,3,5-Triazines, due to their characteristics of C₃ symmetry, have found applications in supramolecular chemistry, including multidimensional crystal engineering, production of nano-coordinated compounds, etc. Synthetic methods for triazines and their derivatives include aerobic oxidation, C–H functionalization, dehydrogenation, cross-cyclotrimerization, ring-closure reactions, and coupling reactions, often in the presence of a base or catalyst. In this review, we have summarised various methods for the synthesis of 1,3,5-triazines in good to moderate yields. The effects, factors, and applicability of the summarised reactions are also explained wherever possible to provide a detailed insight into the synthesis of the desired s-triazines.