反应 #1140

反应方程式

5-bromo-3-(3,3-dibromo-1-methyl-5-pyrrolidin-2-onyl)pyridine

tellurium

Sodium borohydride

ethyl acetate

→

5-bromo-3-(1-methyl-5-pyrrolidin-2-onyl)pyridine

收率 68.0%

溶剂

ethanol

反应条件

后处理

1. 1
   温度The mixture was heated
2. 2
   温度under reflux for 0.25 h
3. 3
   过滤the solution was filtered through Celite
4. 4
   浓缩concentrated in vacuo
5. 5
   workup.ADDITION1M HCl (10 mL) was added to the residue
6. 6
   萃取After extraction with ethyl acetate (50 mL) the organic phase
7. 7
   其他was separated
8. 8
   萃取The aqueous phase was extracted with ethyl acetate (2×50 mL)
9. 9
   洗涤the combined organic phases were washed with brine (30 mL)
10. 10
    干燥dried (MgSO4)
11. 11
    浓缩concentrated
12. 12
    其他This material was chromatographed on silica gel with ethyl acetate:hexane (1:1) as eluant

实验过程

Sodium borohydride (862 mg, 22.8 mmol) was dissolved in ethanol (20 mL) and tellurium metal powder (1.45 g, 11.4 mmol) was added in portions. The mixture was heated under reflux for 0.25 h and 5-bromo-3-(3,3-dibromo-1-methyl-5-pyrrolidin-2-onyl)pyridine (775 mg, 1.9 mmol) was added to the solution at 25° C. After stirring for 2 h, ethyl acetate (50 mL) was added and the solution was filtered through Celite and concentrated in vacuo. 1M HCl (10 mL) was added to the residue and the solution was adjusted to pH 11 with solid potassium carbonate. After extraction with ethyl acetate (50 mL) the organic phase was separated. The aqueous phase was extracted with ethyl acetate (2×50 mL) and the combined organic phases were washed with brine (30 mL), dried (MgSO4) and concentrated. This material was chromatographed on silica gel with ethyl acetate:hexane (1:1) as eluant to afford 5-bromo-3-(1-methyl-5-pyrrolidin-2-onyl)pyridine as a solid (329 mg, 68%). M.p. 85°-87° C.; 1H NMR (CDCl3, 300 MHz): δ 8.66 (d, J=2 Hz, 1H), 8.42 (d, J=2 Hz, 1H), 7.68 (t, J=2 Hz, 1H), 4.56 (t, J=7 Hz, 1H), 2.71 (s, 3H), 2.45-2.65 (m, 2H), 1.80-1.95 (m, 2H).

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