Macromolecular engineering in functional polymers via ‘click chemistry’ using triazolinedione derivatives

It has been almost two decades since the concept of ‘click’ chemistry was anchored in the monumental field of chemistry. Later, numerous chemical approaches have been implemented that exhibit features kindred to ‘click’ chemistry toolbox. Unlike the synthesis of organic compounds involving typical purification procedures, the modular and orthogonal ‘click’ concept substantially embraces the material research community with delineating innumerable macromolecular architectures. In polymer chemistry, there are various types of ‘click’ reactions like copper (I) catalyzed alkyne-azide (CuAAC), strain promoted alkyne-azide cycloaddition (SPAAC), Diels-Alder, Alder-ene, thiol-ene, thio-bromo, etc., are used to prepare different functional polymers. Among the various ‘click’ reactions, recently, the ultrafast ‘click’ modification based on different 1,2,4-triazoline-3,5-dione (TAD) derivatives has gained tremendous attention in the broad platform of polymer research. Similar to singlet oxygen, the heterocyclic TAD reagents undergo ‘click’ conjugation within a concise timescale. Following the uncovering of the conventional routes for synthesizing TADs, few spellbinding categories of research have been carried out to develop different functional polymers for diverse applications. The perspective of this review is to cover the recent fascinating outcomes from TAD based ultrafast ‘click’ modification of macromolecules. This review highlights the present state-of-the-art of synthesis of new TAD molecules and their use in designing different macromolecular systems with remarkable features based on ultrafast TAD ‘click’ chemistry.