Methanol → Methyl 2-bromo-4-methylbenzoate
Reaction equation
[Br:1][C:2]1[CH:10]=[C:9]([CH3:11])[CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].S(=O)(=O)(O)O.[CH3:17]O>>[Br:1][C:2]1[CH:10]=[C:9]([CH3:11])[CH:8]=[CH:7][C:3]=1[C:4]([O:6][CH3:17])=[O:5]Participants
4
Conditions
- Temperature
- 70 °C
Procedure
To a solution of 2-bromo-4-methylbenzoic acid (10 g) in MeOH (50 ml) was added dropwise concentrated sulfuric acid (10 ml) at 0° C. The mixture was heated at 70° C. for 2 hours. After cooling to ambient temperature, the methanol was removed under reduced pressure. The residue was poured into ice-water (100 ml). The mixture was extracted with EtOAc (×2). The combined organic layers were washed with NaHCO3 (aq. sat. Note: gas evolution), brine, dried over MgSO4, filtered, and concentrated to give the product as a clear oil. Yield: 10.5 g, 99%. 1H NMR (400 MHz, Chloroform-d) δ 7.73 (d, 1H), 7.50 (d, 1H), 7.19-7.11 (m, 1H), 3.92 (s, 3H), 2.36 (s, 3H).
Workup
- temperatureAfter cooling to ambient temperature
- customthe methanol was removed under reduced pressure
- additionThe residue was poured into ice-water (100 ml)
- extractionThe mixture was extracted with EtOAc (×2)
- washThe combined organic layers were washed with NaHCO3 (aq. sat. Note: gas evolution), brine
- dry with materialdried over MgSO4
- filtrationfiltered
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-17956312e1384cf7b480d9e48a3a3353
- Source dataset
- uspto-grants-2014_10
- Patent number
- US08871790B2
Reaction notes
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