Copper oxide nanoparticle catalysed synthesis of imidazo[1,2-a]pyrimidine derivatives, their optical properties and selective fluorescent sensor towards zinc ion

• Published in: Tetrahedron letters Vol. 59; no. 24; pp. 2341 - 2346
• Main Authors: Rawat, Manish, Rawat, Diwan S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 13.06.2018
• Subjects: A3 & KA2 coupling reactions; Decarboxylative strategies; Green & sustainable chemistry; Magnetically recoverable; Propargyl amines; Decarboxylative strategies; Propargyl amines; Magnetically recoverable; Green & sustainable chemistry; A3 & KA2 coupling reactions
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2018.05.005

[Display omitted] •Solvent free synthesis of fused imidazo[1,2-a]pyrimidines via A3 coupling.•Use of copper oxide nanoparticles as a recyclable catalyst.•Short reaction time and good yield.•Imidazo[1,2-a]pyrimidines act as a sensor for zinc ion. Synthesis of biologically active fused imidazo[1,2-a]pyrimidines were achieved via A3 coupling involving 2-aminobenzimidazole, aldehyde and terminal alkyne, followed by 6-endo-dig cyclization using copper oxide nanoparticles under solvent free condition. Further optical properties of imidazo[1,2-a]pyrimidines were studied which showed the effect of electron-donating and electron-withdrawing substitution on the fluorescence intensities of these compounds. Out of 20 compounds, 2,4-bis(4-methoxyphenyl)benzo[4,5]imidazo[1,2-a]pyrimidine can act as a fluorescent sensor for zinc ion with detection limit 4.74 μM, which is much lower than the maximum allowable zinc concentration in drinking water by WHO.