3-Chloro-4-hydroxybenzoic acid hemihydrate → Methyl 3-chloro-4-hydroxybenzoate

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-chloro-4-hydroxy-benzoic acid hemihydrate (9.08 g, 50 mmol) in methanol (150 mL) is added slowly (conc)sulfuric acid (22.5 mL). The resulting solution is heated to 55° C. and stirred 2 hours then cooled to 20° C. Poured solution into ice and extracted with ether. The organic is washed with brine, dried over MgSO4 and concentrated. The residue is purified by flash chromatography (eluting with 30% ethyl acetate in hexanes) to give 9.5 g of title compound as a white crystalline solid. 1H NMR (CDCl3) δ 3.90 (s, 3H), 7.06 (d, J=9 Hz, 1H), 7.88 (dd, J=9, 2 Hz, 1H), 8.05 (d, J=2 Hz, 1H). MS (EI) m/z 186/188 (M+, Cl).

Provenance & Evidence