Síntese telescópica de calcogenil-imidazo[1,2-α]piridinas calcogenadas (S, Se, Te) utilizando condições verdes

Abstract

In this work, a telescope methodology using the I₂/UHP catalytic system was developed for the synthesis of 3-selenyl-2-phenylimidazo[1,2-α]pyridines. Imidazopyridines possess biological activities such as anxiolytic effects, making them relevant in the pharmaceutical industry. Selenium also presents therapeutic properties like antioxidant, anti-inflammatory, and antitumor activities. The combination of selenium with imidazopyridine structures may enhance biological potential. Traditional methods often involve multiple steps and purifications. In contrast, the telescopic approach used here reduces reaction steps, waste, and processing, aligning with green chemistry principles. The oxidant urea-hydrogen peroxide (UHP) and green solvent d-limonene were employed. Optimal conditions (time, temperature, reagent ratios) were established for synthesizing 3-chalcogenyl-2-phenylimidazo[1,2-α]pyridines from aminopyridines, bromoacetophenones, and dichalcogenides. Structural variation of substrates led to 15 synthesized compounds, including two novel structures (5l and 5m), highlighting the efficiency and sustainability of the proposed methodology.