A Triazine Based Sulfonic Acid Anchored Porous Organic Polymer as an Efficient Heterogeneous Acid Catalyst for the Hantzsch Pyridine Synthesis

ABSTRACT A triazine‐based porous organic polymer as a novel acid catalyst has been prepared for the efficient synthesis of 1,4‐dihydropyridine and their derivatives, known as Hantzsch pyridines, under mild reaction conditions. A straightforward one‐pot method was adopted for the synthesis of triazine‐based porous organic polymer which is anchored by sulfonic acid groups. The presence of multiple sulfonic acid sites in the polymer framework, facilitates the electrophilic activation of the carbonyl groups of both aldehyde and 1,3‐dicarbonyl compound, enabling the formation of main intermediates and thereby promoting the efficient formation of 1,4‐dihydropyridines. A plausible reaction mechanism for the synthesis of 1,4‐DHPs catalyzed by POP CCDABS has also been proposed. This catalyst offers significant advantages, including easy one‐step preparation, high product yield, mild reaction conditions, and excellent reusability.