反应详情

A mixture of 2-amino-6-nitrobenzoic acid (11.9 g, 65.3 mmol), methyl p-toluenesulfonate (15.1 g, 81.1 mmol) and triethylamine (6.60 g, 65.3 mmol) in DMF (170 ml) was stirred under N2 at 60° for 18 hours. After removing DMF at 60° and 0.2 mm pressure, the residue was dissolved in ETOAc and washed with a saturated solution of NaHCO3 followed by a saturated aqueous solution of NaCl. The EtOAc extract was dried (Na2O4), filtered and concentrated under reduced pressure. Flash chromatography over silica gel and elution with 50% toluene-50% CHCl3 gave methyl 2-amino-6-nitrobenzoate (7.6 g, 59.4%), m.p. 105°-107°.

1. customAfter removing DMF at 60°
2. dissolution0.2 mm pressure, the residue was dissolved in ETOAc
3. washwashed with a saturated solution of NaHCO3
4. extractionThe EtOAc extract
5. customwas dried (Na2O4)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. washFlash chromatography over silica gel and elution with 50% toluene-50% CHCl3