Ethyl 2-fluoro-4-nitrobenzoate → Ethyl 4-Amino-2-fluorobenzoate

HRID 398056Notes

Reaction equation

HRID 398056 reaction equation
[H][H].[F:3][C:4]1[CH:14]=[C:13]([N+:15]([O-])=O)[CH:12]=[CH:11][C:5]=1[C:6]([O:8][CH2:9][CH3:10])=[O:7]>C(OCC)(=O)C.[Pd]>[NH2:15][C:13]1[CH:12]=[CH:11][C:5]([C:6]([O:8][CH2:9][CH3:10])=[O:7])=[C:4]([F:3])[CH:14]=1

Participants

5

Reactant 2

HCID 10727300Ethyl 2-fluoro-4-nitrobenzoateHCID 178418361HCID 178418361, compound

Product 1

HCID 10797532Ethyl 4-Amino-2-fluorobenzoate

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 8857Ethyl AcetateSolvent

Procedure

To a mixture of 2-fluoro-4-nitrotoluene (1.0 g, 6.4 mmol, Aldrich) and Na2Cr2O7 (2.74 g, 8.4 mmol) in 13.7 ml of HOAc was added slowly 6.83 ml of H2SO4. This mixture was slowly heated to 90° C. for 1 h to give a greenish heterogeneous solution. The mixture was cooled to room temperature and diluted with ethyl acetate. The PH of the solution was adjusted to 4 with NaOH (aq.). The mixture was extracted with more ethyl acetate. The organic layer was washed with NaHCO3 (sat.), then brine and dried over Na2SO4. After filtration, the solution was concentrated to dryness which then was dissolved in 6 ml of SOCl2, and heated at 80° C. for 1 h. The excess of SOCl2 was removed under reduced pressure and the residue was dissolved in 5 ml of CH2Cl2, 2 ml of EtOH and 2 ml of pyridine. The mixture was stirred at room temperature for 2 h and concentrated to dryness. Ethyl 2-fluoro-4-nitrobenzoate was obtained as a white solid after column chromatography of the residue with ethyl acetate/hexane (1/9). This solid was then dissolved in 10 ml of ethyl acetate, and Pd/C (50 mg) was added. Hydrogenation with a hydrogen balloon converted ethyl 2-fluoro-4-nitrobenzoate into the title compound.

Sources & evidence

ORD record
ord-e5a3a1ff72df4ac991eb8f9e1898f704
Source dataset
uspto-grants-2003_08
Patent number
US06610744B2

Reaction notes

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