反应详情

Trimethylacetyl chloride (5.57 g) was added dropwise to a vigorously stirred mixture of methyl 2-amino-6-hydroxybenzoate (prepared according to Comess et al, US2004 0167128, 5.15 g) and sodium bicarbonate (7.76 g) in a mixture of water (40 mL) and ethyl acetate (100 mL) and the mixture was stirred for one hour. Further trimethylacetyl chloride (5.57 g) was added and the mixture stirred overnight. The organic layer was separated, dried (Na2SO4) and filtered. The filtrate was concentrated in vacuo and the residue was triturated with pentane. The solid was collected by filtration and purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 0-25% to give methyl 2-(2,2-dimethyl-propionylamino)-6-hydroxy-benzoate (4.96 g) as a white solid.

1. stirringthe mixture stirred overnight
2. customThe organic layer was separated
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationThe filtrate was concentrated in vacuo
6. customthe residue was triturated with pentane
7. filtrationThe solid was collected by filtration
8. custompurified by chromatography on silica
9. washeluting with a mixture of ethyl acetate and cyclohexane with a gradient of 0-25%