[Synthesis]
Methyl 3-bromo-4-hydroxybenzoate (12, 0.185 g, 0.80 mmol) in anhydrous CH2Cl2 (14 mL) was added slowly to a THF solution of DIBAL-H (1.0 M, 1.92 mL, 1.92 mmol) at -78 °C. The reaction mixture was stirred at -78 °C for 1 h before the reaction was quenched by addition of MeOH and water. Subsequently, saturated potassium sodium tartrate solution was added and stirring was continued for 1 hour. The aqueous layer was extracted with ethyl acetate (3 x 20 mL), the organic layers were combined, washed sequentially with 10% aqueous NaHCO3 and water, dried over anhydrous Na2SO4, filtered and concentrated. The residue was purified by fast column chromatography (eluent: ethyl acetate/hexane, 1:1) to afford the target product 3-bromo-4-hydroxybenzenemethanol (13, 0.111 g, 68% yield) as a white solid. The product characterization data were as follows: melting point 125 °C; elemental analysis (measured value: C, 41.45; H, 3.42. theoretical value of C7H7BrO2: C, 41.41; H, 3.48); thin-layer chromatography Rf-value of 0.6 (unfolding reagent: ethyl acetate/hexanes, 65:35); IR (Nujol) νmax 3510, 3060, 2982, 1610 , 1505, 1425, 1270, 905, 750, 710 cm-1; 1H NMR (300MHz, DMSO-d6) δ: 7.38 (d, J=2.0Hz, 1H), 7.08 (dd, J=2.0,8.2Hz, 1H), 6.87 (d, J=8.2Hz, 1H), 5.07 (t, J=5.7 Hz, 1H), 4.34 (d, J=5.7Hz, 2H); 13C NMR (75MHz, DMSO-d6) δ: 153.3, 135.4, 131.6, 127.6, 116.5, 109.4, 62.5. |