反应详情

A mixture of 2-bromo-1-(5-acetoxy-6,7-dimethyl-benzofuran-2-yl)-ethanone (30 mg), methylaminoethanol (7 mg), and potassium carbonate (20 mg) in acetone (10 mL) was stirred at RT for 1 h. The mixture was poured into water and extracted with ethylacetate. The organic layer was dried and evaporated followed by purification by silica gel column chromatography eluting with 5% MeOH in DCM to give 20 mg of 2-(5-hydroxy-6,7-dimethyl-benzofuran-2-yl)-4-methyl-morpholin-2-ol as an oil, and was converted into the HCl salt. The NMR showed an equilibrium of the hemiketal and ketone form. 1H NMR (CDCl3, 300 MHz) δ: 7.51, 7.26 (2s, combined, 1H), 7.06, 6.87 (2s, combined 1H), 7.06, 6.87 (2s, combined 1H) 4.2-3.7 (m, 2H), 3.2-2.8 (m, 4H), 2.5-2.0 (m, 12H) ppm. 13C NMR (CDCl3, 75 MHz) δ: 189.26, 170.43, 170.18, 156.79, 152.53, 145.71, 125.79, 125.39, 124.46, 121.73, 113.88, 113.14, 111.52, 104.28, 92.48, 63.55, 62.62, 61.11, 59.68, 54.75, 46.37, 21.30, 13.48, 13.02, 12.90 ppm. M/S 320 (M+H+).

1. extractionextracted with ethylacetate
2. customThe organic layer was dried
3. customevaporated
4. customfollowed by purification by silica gel column chromatography
5. washeluting with 5% MeOH in DCM