Water → Methyl 4-bromo-2-nitrobenzoate
Reaction equation
[Br:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([N+:11]([O-:13])=[O:12])[CH:3]=1.N1(C2CCCCCCCCCC2)CCCNCCCCC[CH2:15]1.CI.O>CN(C=O)C>[Br:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([O:8][CH3:15])=[O:7])=[C:4]([N+:11]([O-:13])=[O:12])[CH:3]=1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
To a stirred solution of 4-bromo-2-nitrobenzoic acid (3.81 g, 15 mmol) in DMF (30 mL) at 0° C. was added 1,8-diazabicycloundecane (DBU; 10.3 mL, 75 mmol) followed by MeI (4.67 mL, 75 mmol). The mixture was stirred for 15 min at 0° C., then was allowed to warm to rt and was stirred overnight. The mixture was poured into water and extracted with EtOAc (2×). The combined organic extracts were washed with water (2×), dried (MgSO4), and concentrated. The residue was purified by flash chromatography (hexanes/EtOAc) to afford methyl 4-bromo-2-nitrobenzoate as a pale yellow solid (3.52 g, 90%). To a solution of the nitrobenzoate (3.52 g, 13.5 mmol) in 1:1 EtOAc/DCM (30 mL) at rt was added SnCl2.2H2O (15.27 g, 67 mmol). After 18 h, the mixture was concentrated, diluted with satd. aq. NaHCO3, and extracted with DCM (3×). The combined organic layers were dried (MgSO4) and concentrated to provide the desired aminobenzoate as a white solid (2.89 g, 93%). 1H NMR (400 MHz, CDCl3): 7.70 (d, J=8.6, 1H), 6.84 (d, J=1.9, 1H), 6.75 (dd, J=8.6, 1.9, 1H), 5.78 (br s, 2H), 3.86 (s, 3H).
Workup
- temperatureto warm to rt
- stirringwas stirred overnight
- extractionextracted with EtOAc (2×)
- washThe combined organic extracts were washed with water (2×)
- dry with materialdried (MgSO4)
- concentrationconcentrated
- customThe residue was purified by flash chromatography (hexanes/EtOAc)
Sources & evidence
- ORD record
- ord-1b2a43453c5a4d10a5003045539363e9
- Source dataset
- uspto-grants-2010_12
- Patent number
- US07855292B2
Reaction notes
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