[H-].[Na+].C(S)C.[Br:6][C:7]1[C:12]2[CH:13]=[C:14]([CH2:16][O:17][CH3:18])[O:15][C:11]=2[C:10]([O:19]C)=[CH:9][CH:8]=1>CN(C)C=O>[Br:6][C:7]1[C:12]2[CH:13]=[C:14]([CH2:16][O:17][CH3:18])[O:15][C:11]=2[C:10]([OH:19])=[CH:9][CH:8]=1To a stirred solution of sodium hydride (334 mg, 60% in mineral oil) in dry N, N-dimethylformamide (25 ml) under an atmosphere of dry nitrogen at room temperature was added dropwise ethane thiol (0.586 ml). After stirring for 20 minutes a solution of 4-bromo-7-methoxy-2-methoxymethylbenzofuran (2.04 g) in N,N-dimethyl-formamide (7 ml) was added dropwise and the reaction mixture was heated at 160° C. for 2 hours. The reaction was cooled and the solvent removed in vacuo. The residue was dissolved in ethyl acetate (70 ml) and washed with ammonium chloride solution (70 ml). The organic extract was dried over magnesium sulphate, filtered and the solvent removed in vacuo. Purification by column chromatography on silica eluting with 50% ethyl acetate in hexane afforded the title compound as a white solid (1.21 g).
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