Boron tribromide → 2-Bromo-5-hydroxybenzaldehyde

To the solution of 2-bromo-5-methoxy-benzaldehyde (10 g, 46.5 mmol) at −78° C. is added BBr3 (25 g, 93.75 mmol) and allowed to warm to room temperature. After 2 h, the reaction is quenched with water and extracted with ethyl acetate. The combined organic layers are washed with water, brine, dried over MgSO4, concentrated and purified by column chromatography to afford 3.6 g of 2-bromo-5-hydroxy-benzaldehyde. To the solution of 2-bromo-5-hydroxy-benzaldehyde (1.45 g, 7.2 mmol in benzene (30 ml) and THF (6 ml) is added 1,3-propanediol (2.74 g, 36 mmol) and TsOH (37 mg, 0.22 mmol). The mixture is refluxed for 24. After cooling down, the solvent is evaporated. The residue is loaded on silica and purified by column chromatography to afford the titled compound (2.3 g) as brown oil.

1. customthe reaction is quenched with water
2. extractionextracted with ethyl acetate
3. washThe combined organic layers are washed with water, brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated
6. custompurified by column chromatography

ORD record

ord-05c55aa8efa74b5981c628f0e8eae0b6

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08609892B2