反应详情

A mixture of 5-(tert-butoxycarbonylamino-methyl)-2-nitro-benzoic acid methyl ester (52.5 g, 169.3 mmol), lithium hydroxide (4.86 g, 203.1 mmol) in methanol (546 mL) and water (273 mL) was stirred with a mechanical stirrer at room temp overnight. The methanol was evaporated, and to the aqueous solution, was added 1 N HCl (270 mL) to form the precipitate. Ether (350 mL) was added, and the mixture was stirred at 0° C. for 2 hours. The mixture was evaporated. To the residue, was added water (500 mL). The aqueous layer was extracted with methylene chloride (3×100 mL). The combined organic layers were separated, dried over magnesium sulfate, and concentrated to give 5-(tert-butoxycarbonylamino-methyl)-2-nitro-benzoic acid as a brown oil (21.0 g, 41% yield). The product was used in the next step without further purification.

1. customThe methanol was evaporated
2. additionto the aqueous solution, was added 1 N HCl (270 mL)
3. customto form the precipitate
4. stirringthe mixture was stirred at 0° C. for 2 hours
5. customThe mixture was evaporated
6. additionTo the residue, was added water (500 mL)
7. extractionThe aqueous layer was extracted with methylene chloride (3×100 mL)
8. customThe combined organic layers were separated
9. dry with materialdried over magnesium sulfate
10. concentrationconcentrated