Hydrochloric Acid → 7-fluoro-4-methoxy-1-benzothiophen-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of N-(7-fluoro-4-methoxy-1-benzothien-2-yl)-N,N-dimethylamine (1.73 g, 7.7 mmol) in THF (25 mL) was added aqueous hydrochloric acid (1 N, 25 mL) and this was heated to 80° C. for 3 h. After cooling to room temperature then extracted with ether (100 mL), dried (MgSO4) and the solvent evaporated in vacuo to give a yellow solid. The residue was purified by flash chromatography in 5% ethyl acetate in hexane to give (1.3 g, 84%) of the title compound; δH (300 MHz, CHCl3) 6.97–6.87 (1H, m, ArH), 6.62–6.55 (1H, m, ArH), 3.91 (2H, s, CH2) and 3.85 (3H, s, OCH3).

Provenance & Evidence