反应详情

To a solution of (5-bromo-pyridin-2-yl)-pyrrolidin-3-yl-methanone (0.35 g, 1.35 mmol) in methanol (68 mL), add acetic acid (0.15 mL, 2.7 mmol), and formaldehyde (0.33 g, 4.1 mmol, 37% aqueous solution). After 15 min, add sodium triacetoxyborohydride (0.86 g, 4.1 mmol) and allow the mixture to stir at RT for 1 h. Concentrate the reaction mixture, dissolve in CH2Cl2, and wash with saturated NaHCO3. Back-extract the aqueous with CH2Cl2. Wash the combined organic layer with water, dry over Na2SO4, filter, and concentrate. Purify the crude material by flash chromatography, eluting with 5-10% MeOH (2N NH3)/CH2Cl2 to give 0.17 g (47%) of the title compound. LC-MS/ES m/z (79Br) 270 [M+H]+.

1. concentrationConcentrate the reaction mixture
2. dissolutiondissolve in CH2Cl2
3. washwash with saturated NaHCO3
4. extractionBack-extract the aqueous with CH2Cl2
5. washWash the combined organic layer with water
6. dry with materialdry over Na2SO4
7. filtrationfilter
8. concentrationconcentrate
9. customPurify the crude material by flash chromatography
10. washeluting with 5-10% MeOH (2N NH3)/CH2Cl2