反応 #328952

反応方程式

Potassium cyanide

potassium cyanide

3-bromomethyl-2,6-dichloro-pyridine

3,3-dibromomethyl-2,6-dichloro-pyridine

2,6-dichloro-3-methyl-pyridine

3-bromomethyl-2,6-dichloro-pyridine

→

(2,6-dichloro-pyrid-3-yl)-acetonitrile

溶媒

ethanol

water

反応条件

後処理

1. 1
   workup.ADDITIONwas added dropwise at 40° C. over a period of 30 minutes
2. 2
   温度The reaction mixture was heated
3. 3
   温度to reflux for 3 hours
4. 4
   温度The reaction mixture was cooled to 40° C.
5. 5
   温度The reaction mixture was heated
6. 6
   温度to reflux for a further 3 hours
7. 7
   ろ過The reaction mixture was filtered
8. 8
   その他to remove the solids
9. 9
   洗浄the solids were washed with ethyl acetate
10. 10
    濃縮The combined filtrates were concentrated
11. 11
    workup.ADDITIONThe residue was diluted with ethyl acetate
12. 12
    洗浄The organic solution washed with aqueous sodium hydrogen carbonate (saturated) and brine
13. 13
    乾燥dried over magnesium sulfate
14. 14
    濃縮concentrated
15. 15
    その他This residue was purified by column chromatography on silica gel (eluent: ethyl acetate/hexane from 3:100 to 1:1)

実験手順

Potassium cyanide (1.0 g) was dissolved in water by heating to 40° C. A mixture of 3-bromomethyl-2,6-dichloro-pyridine, 3,3-dibromomethyl-2,6-dichloro-pyridine, and 2,6-dichloro-3-methyl-pyridine (Example 4.1) (3.2 g) suspended in ethanol (20 ml) was added dropwise at 40° C. over a period of 30 minutes. The reaction mixture was heated to reflux for 3 hours. The reaction mixture was cooled to 40° C. and another equivalent of potassium cyanide was added. The reaction mixture was heated to reflux for a further 3 hours and then stored at ambient temperature for 16 hours. The reaction mixture was filtered to remove the solids and the solids were washed with ethyl acetate. The combined filtrates were concentrated. The residue was diluted with ethyl acetate. The organic solution washed with aqueous sodium hydrogen carbonate (saturated) and brine, dried over magnesium sulfate, and concentrated. This residue was purified by column chromatography on silica gel (eluent: ethyl acetate/hexane from 3:100 to 1:1) to give slightly impure (2,6-dichloro-pyrid-3-yl)-acetonitrile (1.5 g) which solidified on standing. This material was used without further purification. 1H-NMR (400 MHz, CDCl3): 3.83 (s, 2H), 7.37 (d, 1H), 7.85 (d, 1H) ppm.

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