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Superparamagnetic nanoparticle-catalyzed coupling of 2-amino pyridines/pyrimidines with trans-chalcones.

ABSTRACT: An aerobic coupling of 2-aminopyrimidines or 2-aminopyridines with trans-chalcones to afford aroylimidazo[1,2-a]pyrimidines and aroylimidazo[1,2-a]pyridines is reported. Reactions proceed in the presence of CuFe₂O₄ superparamagnetic nanoparticle catalyst, two equivalents of iodine, oxygen oxidant, and 1,4-dioxane solvent. The catalyst is superior to many common copper or iron complexes. Copper ferrite could be easily separated by magnetic decantation and reused up to 5 times without a major loss of activity. The method described here marks a rare example of using a simple, heterogeneous catalyst for synthesis of fused heterocycles. To our best knowledge, aroylimidazo[1,2-a]pyrimidines and aroylimidazo[1,2-a]pyridines were not previously synthesized using this protocol.

SUBMITTER: Nguyen OTK

PROVIDER: S-EPMC9060791 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Superparamagnetic nanoparticle-catalyzed coupling of 2-amino pyridines/pyrimidines with trans-chalcones.

Nguyen Oanh T K OTK Ha Pha T PT Dang Ha V HV Vo Yen H YH Nguyen Tung T TT Le Nhan T H NTH Phan Nam T S NTS

RSC advances 20190213 10

An aerobic coupling of 2-aminopyrimidines or 2-aminopyridines with trans-chalcones to afford aroylimidazo[1,2-a]pyrimidines and aroylimidazo[1,2-a]pyridines is reported. Reactions proceed in the presence of CuFe2O4 superparamagnetic nanoparticle catalyst, two equivalents of iodine, oxygen oxidant, and 1,4-dioxane solvent. The catalyst is superior to many common copper or iron complexes. Copper ferrite could be easily separated by magnetic decantation an ...[more]

PMID: 35515937

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