Indium(III) bromide has been used for the first time for the synthesis of imidazo[1,2-a]pyridines in a one-pot operation from 2-aminopyridine, aldehydes, and alkynes. InBr3 was found to be more effective for the activation of both alkyne and imine derived from aryl aldehyde and 2-aminopyridine.
溴化铟(III)首次用于由一锅操作由2-氨基吡啶,醛和炔烃合成咪唑并[1,2- a ]吡啶。发现InBr 3对于活化衍生自芳基醛和2-氨基吡啶的炔烃和亚胺都更有效。
Imidazo[1,2-a]pyridine A3-Coupling Catalyzed by a Cu/SiO2 Material
作者:Helena de Salles、Tiago da Silva、Cátia Radatz、Ricardo Affeldt、Edilson Benvenutti、Paulo Schneider
DOI:10.21577/0103-5053.20190089
日期:——
In this work, we report the preparation of a copper-silica material (Cu/SiO2) by a sol-gel methodology and its characterization concerning composition and textural properties. The Cu/SiO2 material was successfully applied as a Lewis acid heterogeneous catalyst for the A(3)-coupling from 2-aminopyridine, aldehydes and alkynes to imidazo[1,2-a]pyridines (45-82%). which are relevant pharmacological scaffolds. The synthesis shows a number of advantages, such as easy separation from the reaction media and the minimal formation of metal aqueous wastes. Investigation of the mechanism supports the involvement of the formation of reaction intermediates inside the pores of the mesoporous material prior to 5-exo-dig cyclization.
Magnetic nanostructure-anchored mixed-donor ligand system based on carboxamide and N-heterocyclic thiones: An efficient support of CuI catalyst for synthesis of imidazo[1,2-a]pyridines in eutectic medium
作者:Arefe Salamatmanesh、Akbar Heydari
DOI:10.1016/j.apcata.2021.118306
日期:2021.8
nanocatalyst has been demonstrated for the one-pot synthesis of imidazo[1,2-a]pyridine derivatives viathree-componentreaction of 2-aminopyridines, aldehydes and alkynes using tetrabutyl ammonium bromide/glycerol (TBAB/glycerol) deep eutectic mixture as a sustainable medium. The nanocatalyst has exhibited high activity and stability under the reaction conditions with a negligible copper leaching, which