Synthesis and Characterization of Novel Pyrimido [1,2-a] benzimidazole and its Derivatives


  • Fadhel R. Hafedh Department of Chemistry, College of Science, Mustansiriyah University, Baghdad, IRAQ.
  • Hamid H. Mohammed Department of Chemistry, College of Science, Mustansiriyah University, Baghdad, IRAQ
  • Zainab N. Mageed Unit of Research Polymer, College of Science, Mustansiriyah University, Baghdad, IRAQ.



pyrmidines, benzimidazole


A few pyrimido[1,2-a] benzimidazole derivatives had been synthesized, derived from 4-amino-2-(4-chloro or bromophenyl) -1,2-dihydropyrimido[1,2-a] benzimidazole-3-carbonitrile (4 or 5) is made through one pot three components condensation reaction of 1H-benzimidazol-2-amine (1) with p-chloro or bromobenzaldehyde (2) and malononitrile (3). First part of these derivatives prepared by reaction compound (4 or 5) with acetic acid or propionic acid in presence POCl3 to give pyrmidino rings (6-9). Second part of derivatives were prepared by reaction compound (4 or 5) with benzoyl chloride or phenylisothiocyanate or cyclohexanone to give cyclic compounds (10-15) respectively. All these derivatives characterized by FT-IR and HNMR spectroscopy analysis in addition to physical properties.


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How to Cite

F. R. . Hafedh, H. H. Mohammed, and Z. N. . Mageed, “Synthesis and Characterization of Novel Pyrimido [1,2-a] benzimidazole and its Derivatives”, MJS, vol. 33, no. 1, pp. 15–20, Mar. 2022.



Chemical Science