Synthesis, Characterization, and DFT Calculation of some New Pyrimidine Derivatives and Theoretical Studies on the Corrosion Inhibition Performance

In this study, 5-benzoyl-6-phenyl-4- (4- (trifluoromethoxy) phenyl) - 1,2,3,4- tetrahydroxypyrimidine (1); 5-benzoyl-6-phenyl-4- (4- (trifluoromethoxy) phenyl) -1,2,3,4- tetrahydrothioxypyrimidine (2) and 5-benzoyl-6-phenyl-4- (3,5-dimethoxy) phenyl) -1,2,3,4- tetrahydrothioxypyrimidine (3) compounds were prepared via Biginelli condensation reaction using Metal-organic framework (MIL-101) as an active catalyst. It was established to be an active heterogeneous catalyst for a three-component Biginelli condensation reaction with good yields (75-80 %). Moreover, the catalyst could easily be recovered and recycled without any significant loss of its catalytic activity. Also the compounds 5-benzoyl-6-phenyl-3-acetyl-4-(4-hydroxyphenyl)-1,2,3,4- tetrahydrothioxypyrimidine (4) and 5-benzoyl-6-phenyl-3-acetyl-4-(4-trifluoromethoxy)phenyl)- 1,2,3,4-tetrahydrothioxypyrimidine (5) were obtained acetylation reaction. The structures were characterized on the basis of 1 H-NMR, 13 C-NMR, FT-IR, and elemental analysis. And also molecular characterizations of compound 4 were analyzed by X-ray crystal analysis. In addition, the corrosion inhibition activity of synthesized compounds was examined with theoretical calculation using DFT method at the level of B3LYP / 6-31G (d, p).