反应详情

To a mixture of 3-nitrobenzoic acid (0.37 g, 2.2 mmol), 1,1-dimethylethylsulphonamide (0.3 g, 2.2 mmol) and 4-dimethylaminopyridine (0.27 g, 2.2 mmol) in anhydrous dichloromethane (20 ml), under an atmosphere of nitrogen, was added. 1-[3-(dimethylamino)propyl]-3-ethyl carbodiimide hydrochloride (0.42 g, 2.2 mmol). The mixture was stirred at ambient temperature for 22 h. The mixture was extracted with 1M NaOH (50 ml) and the separated aqueous phase acidified using 5M HCl. This was extracted with dichloromethane (5×20 ml), then the combined organic extracts were dried (Na2SO4) and evaporated to dryness. The residue was chromatographed on silica gel using 1% methanol in dichloromethane as the eluant. The title compound (0.53 g, 85%) was isolated as a colourless solid. mp 220° C. 1H NMR (360 MHz, D6-DMSO) δ 1.27 (9H, s), 6.59 (1H, brs), 7.65 (1H, t, J=7.9 Hz), 8.24-8.30 (1H, m), 8.34-8.38 (1H, m), 8.68-8.72 (1H, m).

1. additionunder an atmosphere of nitrogen, was added
2. extractionThe mixture was extracted with 1M NaOH (50 ml)
3. extractionThis was extracted with dichloromethane (5×20 ml)
4. dry with materialthe combined organic extracts were dried (Na2SO4)
5. customevaporated to dryness
6. customThe residue was chromatographed on silica gel using 1% methanol in dichloromethane as the eluant