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Part-IIIExperimentalglacial acetic acid to get crude benzoylacetone. Crude benzoylacetone was purified bydistillation under reduced pressure and obtained as colorless crystalline needles. m.p.61 o C, (m.p. 62 o C) 1 , 100.0 gm, yield 62%.4.1.2 Synthesis of target Dihydropyrimidines1. Synthesis of 5-benzoyl-6-methyl-4-phenyl-3,4-dihydropyrimidin-2(1H)-one (VIIi)from benzyolacetoneA mixture of benzoylacetone (0.0094 mole; 1.0 gm), benzaldehyde (0.0092 mole; 1.5gm), urea (0.0111 mole; 0.67gm) and ethanol (10 ml) were taken in a round bottom flaskand the contents were dissolved by gently heating the flask. Conc. HCl (1-2 drops) wasadded to the flask and then refluxed for 6 hrs. After cooling at room temperature, theprecipitated solid product was filtered and washed with methanol and then recrystallizedfrom ethanol to afford 5-benzoyl-6-methyl-4-phenyl-3,4-dihydropyrimidin-2(1H)-one(VIIi).M.P. : 190-192 o C; Yield: 73%.Mol. Formula : C 18 H 16 N 2 O 2 ; Mol. Wt. 292.12IR (KBr) cm -1 : 3269(γ NH ), 2915(γ C-H ), 1710(γ CO ), 1680(γ CONH ).2. Synthesis of 5-benzoyl-4-(4-chlorophenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-one (VIIii) from benzyolacetoneA mixture of benzoylacetone (0.00852 mole; 1.38 gm), 4-chlorobenzaldehyde (0.0071mole; 1 gm) and urea (0.0106 mole; 0.639 gm) in ethanol (10 ml) were reacted as perprocedure for the compound (VIIi) to get 5-benzoyl-4-(4-chlorophenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-one (VIIii).M.P. : 228-230 o C; Yield 64%.Mol. Formula : C 18 H 15 ClN 2 O 2 ; Mol. Wt. 326.78IR (KBr) cm -1 : 3307(γ NH ), 1706(γ CO ), 1677(γ CONH ), 1586(γ CH ).1 H NMR(DMSO-d 6 )δppm : 1.72 (s, 3H, CH 3 ), 5.46 (d, 1H, H at 4, J = 2.96), 7.34 (br,s, 1H, NH of 1), 7.22-7.49 (m, 9H, Ar-H), 8.94 (s, 1H, NHat 3).474