反应详情

To a stirred solution of 2-Chloro-6-methyl-isonicotinic acid (2 g, 11.65 mmol) in anhydrous THF (40 ml) cooled in an ice bath, was added 1M borane-methyl sulfide complex (6 ml, 60 mmol). After 1 hr, the mixture was stirred for 48 hr at room temperature. The mixture was cooled in an ice bath and conc. HCl (18 ml) was added and stirred for 30 min. The mixture was then basified by addition of 50% aqueous NaOH (15 ml). The product was extracted with dichloromethane, dried with anhydrous potassium carbonate, filtered, and evaporated in vacuo. The crude product was purified by silica gel column chromatography (eluent, methanol:dichloromethane (5:95)) to afford 1.3 g (71%) of a pale yellow solid; m.p. 112-113° C.; 1H NMR (200 MHz, CDCl3) δ 2.26 (1H, t, J=5.4 Hz), 2.52 (3H, s), 4.70 (2H, d, J=5.4 Hz), 7.15 (1H, s), 7.16 (1H, s); m/z (EI) 157 (M+).

1. additionwas added 1M borane-methyl sulfide complex (6 ml, 60 mmol)
2. temperatureThe mixture was cooled in an ice bath
3. stirringstirred for 30 min
4. extractionThe product was extracted with dichloromethane
5. dry with materialdried with anhydrous potassium carbonate
6. filtrationfiltered
7. customevaporated in vacuo
8. customThe crude product was purified by silica gel column chromatography (eluent, methanol:dichloromethane (5:95))