反应详情

3-Hydroxy-4-nitrobenzoic acid (20.0 g, 109 mmol) in ethanol (250 mg) was refluxed for 6 hr in the presence of dry hydrogen chloride (5 g). The solvent was evaporated and the residue was dissolved in methylene chloride. The solution was washed with sodium bicarbonate until the unreacted material was removed as a precipitate. The organic fraction was finally washed with brine, dried over magnesium sulfate to give a brown solid of 3- hydroxy-4-nitrobenzoic acid ethyl ester (17.1 g): mp 80°-81° C. (crystallized from diethyl ether-hexane); Anal. Calcd for C9H9NO5 : C, 51.19% H, 4.30% N, 6.63% and Found: C, 51.23% H, 4.30% N, 6.79%; ir(CHCl3) 3,260, 1,720, 1,535 and 1,320 cm-1 ; and nmr(CDCl3)δ 1.35 (3H, t), 4.3 (2H, q), 7.7 (3H, m) and 10.4 (1H, s).

1. customThe solvent was evaporated
2. dissolutionthe residue was dissolved in methylene chloride
3. washThe solution was washed with sodium bicarbonate until the unreacted material
4. customwas removed as a precipitate
5. washThe organic fraction was finally washed with brine
6. dry with materialdried over magnesium sulfate