Green and Facile Synthesis of Pyrimidine Derivatives Using Choline Chloride-urea Mixture as a Deep Eutectic Solvent or Cerium (IV) Ammonium Nitrate

An efficient and facile synthesis of substituted pyrimidine derivatives through Biginelli type reaction was achieved in high yields via one-pot reaction of aromatic aldehydes, active methylene compounds and urea or thiourea in the presence of choline chloride- urea mixture as a deep eutectic solvent or cerium (IV) ammonium nitrate (CAN) as a catalyst at different conditions. The reaction was carried out using different ratio of CAN in different solvents to determine the optimum conditions. In addition, 2-mercapto-6-oxo- 4-(thiophen-2-yl)-1,6-dihydropyrimidine-5-carbonitrile was employed in the synthesis of pyrimidinylhydrazide and its corresponding hydrazone. The structural formula of all derivatives was confirmed and characterized by their elemental analyses and spectral data (IR, MS, 1H NMR, 13C NMR).