Acetic Acid → Methyl 2,6-diamino-3-bromobenzoate

Iron powder (4.07 g) was added slowly with stirring and cooling to a solution of methyl 6-amino-3-bromo-2-nitrobenzoate (prepared according to Brock et al, Tetrahedron, 1963, 19, 1911, 2.0 g) in a mixture of absolute ethanol (49 mL), acetic acid (5 mL), formic acid (0.7 mL) and water (15 mL). On completion of the addition, the mixture was stirred at room temperature for 2 hours. The mixture was diluted with DCM and water (1:1) then filtered through Celite. The layers were separated and the aqueous layer was extracted with DCM. The combined organic layers were washed with 1M aqueous sodium hydroxide solution, dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was triturated with ether and cyclohexane (1:1) and the solid was collected by filtration to give methyl 3-bromo-2,6-diaminobenzoate (1.34 g) as a pale yellow solid.

1. additionOn completion of the addition
2. stirringthe mixture was stirred at room temperature for 2 hours
3. filtrationthen filtered through Celite
4. customThe layers were separated
5. extractionthe aqueous layer was extracted with DCM
6. washThe combined organic layers were washed with 1M aqueous sodium hydroxide solution
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. customThe filtrate was evaporated to dryness
10. customthe residue was triturated with ether and cyclohexane (1:1)
11. filtrationthe solid was collected by filtration

ORD record

ord-9ef6d389d16d47509fc4b05d4d801cf4

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09266896B2