反应详情

To a solution of 5-bromonicotinic acid (20.00 g, 97.00 mmol) in anhydrous THF (250 mL) was added a solution of BH3 (1 M in THF, 197 mL) slowly at rt over a period of 1 h. The reaction mixture was stirred for 1 h at rt and then was heated at reflux temperature for 5 h. The reaction mixture was cooled to rt and treated with 1 M HCl (100 mL) drop-wise. The resulting mixture was stirred for 1 h and treated with 10% aq. NaOH until pH 10. The solution was then extracted with ethyl acetate (4×200 mL). The combined organic extracts were washed with H2O, dried over anhydrous Na2SO4, filtered and concentrated to yield the crude alcohol (10.71 g). Purification of the crude compound (SiO2: 0-5% 2 M NH3 in MeOH/DCM) gave (5-bromo-pyridin-3-yl)-methanol (4.14 g, 22%).

1. temperaturewas heated
2. temperatureat reflux temperature for 5 h
3. temperatureThe reaction mixture was cooled to rt
4. stirringThe resulting mixture was stirred for 1 h
5. extractionThe solution was then extracted with ethyl acetate (4×200 mL)
6. washThe combined organic extracts were washed with H2O
7. dry with materialdried over anhydrous Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. customto yield the crude alcohol (10.71 g)
11. customPurification of the crude compound (SiO2: 0-5% 2 M NH3 in MeOH/DCM)