Reaktion #69449

Reaktionsgleichung

methyl 4-hydroxybenzoate

bromine

sodium thiosulfate

MeOH

→

methyl 3-bromo-4-hydroxybenzoate

Ausbeute 106.1%

Lösungsmittel

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITat 0° C. and the reaction mixture was left
2. 2
   Sonstigethe temperature around 15° C.
3. 3
   WaschenThe organic layer was washed with water
4. 4
   Trocknenbrine, dried over MgSO4
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated to dryness

Vorschrift

To a stirred suspension of methyl 4-hydroxybenzoate (180 g, 1183 mmol) in DCM (3 L) was added dropwise bromine (64 mL, 1242 mmol) under nitrogen and at 0° C. and the reaction mixture was left to stir at room temperature for 36 h. A solution of sodium thiosulfate (500 mL of a 10% solution) was then added while keeping the temperature around 15° C. followed by addition of MeOH (250 mL). The organic layer was washed with water, then brine, dried over MgSO4, filtered and concentrated to dryness to afford methyl 3-bromo-4-hydroxybenzoate (290 g) as a white solid. Mass Spectrum: m/z [M−H]−=229.

Quelle