反应详情

Methyl pipecolinate hydrochloride (9.0 g, 50 mmol) was mixed with pyridine-2-carbaldehyde (5.4 g, 50 mmol) and triethylamine (5.05 g, 50 mmol) in dichloroethane (180 mL) at room temperature. Sodium triacetoxyborohydride (14.8 g, 70 mmol) was added in one portion. After the reaction mixture was stirred at room temperature for 1.5 h, saturated sodium carbonate was added. Then the mixture was extracted with ethyl acetate. The organic layer was washed with brine, dried with sodium sulfate, filtered and concentrated to give 10.9 g (93.6%) of the title compound as a pale brown oil. 1H NMR (CDCl3), δ(ppm): 8.53 (d, 1H), 7.65 (td, 1H), 7.49 (d, 1H), 7.14 (t, 1H), 3.89 (d, 1H), 3.73 (s, 3H), 3.68 (d, 1H), 3.25 (dd, 1H), 2.97 (m, 1H), 2.25 (m, 1H), 1.85 (m, 2H), 1.30-1.76(m, 4H).

1. extractionThen the mixture was extracted with ethyl acetate
2. washThe organic layer was washed with brine
3. dry with materialdried with sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated