[1,3,5]-Triazine: A Versatile Heterocycle in Current Applications of Organic Chemistry

[1,3,5]-Triazine derivatives have traditionally found applications in analytical chemistry as complexation agents, in electrochemistry as multi-step redox systems and as pesticide or herbicide components in agriculture. In the last years, there has been a growing interest in these compounds that have been used, for example, as templates in multidimensional crystal engineering involving metal complexes for producing nanometre sized oligonuclear coordination compounds, as scaffold in combinatorial chemistry and even as new building blocks in peptidomimetics. The continuous demand to develop synthetic methods for the selective preparation of compounds, under mild conditions and by using non-toxic and not expensive reagents, has prompted the researchers to investigate the use of [1,3,5]-triazine derivatives, such as cyanuric chloride and trichloroisocyanuric acid in organic synthetic applications. For this reason cyanuric chloride, and its derived reagents, are used as dehydrating agents in organic synthesis, as coupling agents in the synthesis of peptides, in the preparation of esters, amides, alkyl chlorides, acyl azides, in the selective protection of hydroxyl groups and so on. From this point of view, this reagent appears as a cheap reactive for many group transformations. 1,3,5-Triazine derivatives are versatile reagents even in the oxidation reactions, such as in Swern type process, and in other important oxidation procedures. In this context, another [1,3,5]-triazine derivative such as trichloroisocyanuric acid, which can be conveniently used even in halogenation reactions, can perform efficient oxidations of alcohols. [1,3,5]-Triazine compounds have been employed both as reagents and intermediates in the synthesis of heterocycles and even as “combinatorial core” for the design of new therapeutics.