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Part-IExperimentalM.P. : 132-134 o C; Yield: 62.6%Mol. Formula : C 9 H 9 NO 5 ; Mol. Wt. 211c. Synthesis of 3, 4-dimethoxy-6-nitrobenzoic acidIn a 250 ml conical flask, 2, 3-dimethoxy-6-nitrobenzaldehyde (0.01 mol) was taken inacetone (100 ml) and aq. solution of KMnO 4 (15 gm in 25 ml water) was chargeddropwise over a period of 20 min in it. The solution was stirred at RT for another 2 hrs.The color of reaction mass changed from dark grey to violet at the end of the addition.The reaction mass was filtered through highflow bed and washed with hot water. Thefiltrate was concentrated to remove excess of acetone and acidify with conc. HCl. Theprecipitate formed were filtered, washed with cold water and dried under vacuum to giveyellow solid (yield 70%) melting at 191-194 o C.M.P. : 191-194 o C (191-194 o C) 10 ; Yield: 70%Mol. Formula : C 9 H 9 O 6 ; Mol. Wt. 213IR(KBr)cm -1 : 1703(γ COOH ), 1529(γ C-NO2 ), 1282(γ Ar-O-CH3 ).d. Synthesis of methyl 3, 4-dimethoxy-6-nitrobenzoateThrough a solution of 2, 3-dimethoxy-6-nitrobezoic acid (2.13 gm; 0.01 mol) in drymethanol (50 ml) dry HCl gas was bubbled over a period of 1-1.5 hrs. Yellow coloredprecipitates were observed after 2-3 hrs of refluxing. The reaction completion wasmonitored by TLC. The reaction mixture was concentrated to half the original volumeand then quenched in ice-water mixture (100 ml). The solution was extracted withchloroform, washed with 10% w/v aq. NaHCO 3 solution, dried and concentrated to givethe yellow colored solid, melting at 141-142 o C.M. P. : 140-142 o C (141-142 o C) 10 ; Yield: 88%Mol. Formula : C 10 H 11 NO 6 ; Mol. Wt. 241IR(KBr)cm -1 : 1726(γ Ar-O-OR ), 1519(γ C-NO2 ), 1288(γ Ar-O-CH3 ).e. Synthesis of methyl 3, 4-dimethoxy-6-aminobenzoate (Ixv)This step involved the reduction of the nitro group of methyl 3, 4-dimethoxy-6-nitrobenzoate with the use of iron powder (activated 80#mesh) and catalytic amount of174