反应详情

Methyl 3-bromo-6-bis-(tert-butoxycarbonyl)amino-2-(4-methylbenzenesulfonyl-oxy)benzoate (Intermediate 10, 6.2 g) was dissolved in methanol (200 mL) and 1M aqueous sodium hydroxide (50 mL) was added. The mixture was stirred at room temperature for 30 minutes. The methanol was removed in vacuo and the residue was diluted with ethyl acetate and water and acidified with acetic acid. The layers were separated and the organic layer was dried (Na2SO4) and filtered. The filtrate was concentrated in vacuo to give methyl 3-bromo-6-bis-(tert-butoxycarbonyl)amino-2-hydroxybenzoate (4.51 g) as a sandy coloured solid.

1. customThe methanol was removed in vacuo
2. additionthe residue was diluted with ethyl acetate and water
3. customThe layers were separated
4. dry with materialthe organic layer was dried (Na2SO4)
5. filtrationfiltered
6. concentrationThe filtrate was concentrated in vacuo