Hydrochloric Acid → 4-Bromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol

Participants

Reaction Steps

A solution of 75 2-(4-Hydroxy-phenyl)-benzofuran-5-ol (0.65 g, 2.9 mmol) in CH3CN (40 mL) was treated with K2CO3 (1 g, 7.1 mmol) followed by portionwise addition of NBS (0.36 g, 2.0 mmol). After stirring for approximately 30 minutes, the reaction was worked up by addition of 2 N HCl followed by 10% Na2SO3aq. and then the CH3CN was stripped off. The aqueous layer was extracted with EtOAc and washed with brine and dried over MgSO4. The reaction mixture was concentrated and chromatographed on silica gel (EtOAc/hexanes; 1:4): Mp 196–198° C.; 1H NMR (DMSO-d6) δ 9.93 (br s, 2 H), 7.76 (d, 2 H, J=8.5 Hz), 7.40 (d, 1 H, J=8.7 Hz), 7.04 (s, 1 H), 6.87 (dd, 2 H, J=9.0 Hz, 3.1 Hz); MS 305/307 (M+H)+.

Provenance & Evidence