An Efficient and Clean One-Pot Synthesis of 3,4-Dihydropyrimidine-2-(1H)-ones Catalyzed by SrCl2·6H2O-HCl in Solvent or Solvent-Free Conditions

참고문헌 (Reference)

1 "General procedure for the preparation of dihydropyrimidinones 4. With a solvent A mixture of aldehyde was heated under reflux for 6 h. After cooling the reaction mixture was poured into crushed ice and stirred for several minutes. The solid products were filtered washed with cold water and a mixture of ethanol-water and then dried. The solid product was recrystalized from ethanol or ethylacetate/n-hexane. Solvent-free the same scale as the above A mixture of aldehyde urea and catalyst was treated with one drop of conc. HCl and heated at 100 oC for 20 min. The reaction mixture was diluted with 5 mL of ethanol stirred and poured into crushed ice. The isolation procedure was the same as above method. The products were characterized by IR 1H NMR and via comparison of their melting points with the reported ones." 10 10 15 5 1 20-,