反应详情

Furo[2,3-c]pyridin-5-ylmethyl acetate (5.17 g, 27.05 mmol) is dissolved in CH2Cl2 (130 mL), layered with saturated NaHCO3 (220 mL), treated with Br2 (8.36 mL, 162.3 mmol) and stirred very slowly for 4.5 h at rt. The mixture is stirred vigorously for 30 min, is diluted with CH2Cl2 (100 mL) and the layers separated. The aqueous layer is extracted with CH2Cl2 (2×100 mL) and the combined organics are concentrated to a small volume under a stream of nitrogen. The solution is diluted with EtOH (200 mL), treated with K2CO3 (22.13 g, 160.1 mmol) and stirred for 2.5 days at rt. The mixture is concentrated to dryness, partitioned between 50% saturated NaCl (200 mL) and CH2Cl2 (5×200 mL), dried over Na2SO4 and concentrated in vacuo to a yellow solid (6.07 g). The crude material is adsorbed onto silica gel (12 g) and chromatographed over 250 g slurry-packed silica gel, eluting with a gradient of 50% EtOAc/hexane to 100% EtOAc. The appropriate fractions are combined and concentrated in vacuo to afford 5.02 g (81%) of (3-bromofuro[2,3-c]pyridin-5-yl)methanol as a white solid. MS (EI) m/z: 227 (M+).

1. stirringThe mixture is stirred vigorously for 30 min
2. customthe layers separated
3. extractionThe aqueous layer is extracted with CH2Cl2 (2×100 mL)
4. concentrationthe combined organics are concentrated to a small volume under a stream of nitrogen
5. additionThe solution is diluted with EtOH (200 mL)
6. stirringstirred for 2.5 days at rt
7. concentrationThe mixture is concentrated to dryness
8. custompartitioned between 50% saturated NaCl (200 mL) and CH2Cl2 (5×200 mL)
9. dry with materialdried over Na2SO4
10. concentrationconcentrated in vacuo to a yellow solid (6.07 g)
11. customchromatographed over 250 g slurry-packed silica gel
12. washeluting with a gradient of 50% EtOAc/hexane to 100% EtOAc
13. concentrationconcentrated in vacuo