3-BROMO-5-HYDROXYBENZOIC ACID

3-Bromo-5-hydroxybenzoic acid is a carboxylic acid derivative and is used in organic synthesis.

[1] Leukotriene b4 inhibitors. Patent no. US20100240678A1

To a solution of NaOH (12.2 g; 305.8 mmol) in 300 mL of water was added 3-bromo-5-iodo-benzoic acid (20 g, 61.2 mmol) and Cu2O (866 mg, 6.1 mmol). The reaction mixture was heated at 100° C. for 24 h. After complete consumption of the starting material, the reaction mixture was cooled to room temperature and filtered through celite. The filtrate was then acidified with 10% aq. HCl and extracted into ethyl acetate. The organic extract was dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford the 3-Bromo-5-hydroxybenzoic acid as a tan solid (12.3 g, 93% yield).

The acid crystallises from H2O (m 238-239o), and with Me2SO4 it yields the 3-methoxy derivative with m 190-191o (from EtOH). [Baddar et al. J Chem Soc 469 1955, Beilstein 10 IV 333.]

[1] Patent: US2010/240678, 2010, A1. Location in patent: Page/Page column 22
[2] Patent: WO2009/77385, 2009, A1. Location in patent: Page/Page column 63
[3] Patent: WO2005/113494, 2005, A2. Location in patent: Page/Page column 118-119