反应详情

750 ml of a 4N solution of hydrogen chloride in 1,4-dioxane were added to 52 g of N-t-butoxycarbonyl-N-methyl-5-methoxy-2-nitroaniline [prepared as described in step (c) above] at room temperature, and the resulting mixture was stirred for 2 hours. At the end of this time, the reaction mixture was freed from the solvent by distillation under reduced pressure, and the resulting residue was mixed with water and ethyl acetate. The mixture was then neutralized by the addition of sodium hydrogencarbonate, after which it was extracted with ethyl acetate. The extract was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. On distilling off the solvent, there were obtained 35.3 g of the title compound, melting at 107°-110° C.

1. distillationAt the end of this time, the reaction mixture was freed from the solvent by distillation under reduced pressure
2. additionthe resulting residue was mixed with water and ethyl acetate
3. additionThe mixture was then neutralized by the addition of sodium hydrogencarbonate
4. extractionafter which it was extracted with ethyl acetate
5. washThe extract was washed with a saturated aqueous solution of sodium chloride
6. dry with materialdried over anhydrous sodium sulfate
7. distillationOn distilling off the solvent