反応 #1709543

反応方程式

1-(3,5-dichloropyridin-4-yl)piperidine-4-carboxamide

vinylene carbonate

→

oil

収率 11.2%

2-(1-(3,5-dichloropyridin-4-yl)piperidin-4-yl)oxazole

収率 11.2%

溶媒

water

—

polyphosphoric acid

反応条件

後処理

1. 1
   温度cooled to r.t.
2. 2
   抽出The mixture was extracted with ethyl acetate (3×50 mL)
3. 3
   洗浄the combined organic extracts were washed with water (100 mL)
4. 4
   乾燥a saturated solution of sodium hydrogen carbonate (50 mL), water (50 mL), brine (50 mL), dried (MgSO4)
5. 5
   濃縮concentrated under reduced pressure

実験手順

To a solution of 1-(3,5-dichloropyridin-4-yl)piperidine-4-carboxamide 23 (0.10 g, 0.36 mmol) in polyphosphoric acid (5 mL) at 80° C. was added vinylene carbonate (35 mg, 0.40 mmol). The mixture was heated at 170° C. for 4 hours, cooled to r.t. and poured into water (200 mL). The mixture was extracted with ethyl acetate (3×50 mL) and the combined organic extracts were washed with water (100 mL), a saturated solution of sodium hydrogen carbonate (50 mL), water (50 mL), brine (50 mL), dried (MgSO4) and concentrated under reduced pressure to furnish a colourless oil (12 mg). The crude product was purified by preparative tlc on silica gel (CH2Cl2, MeOH, 10:1 then hexane, EtOAc, 1:1) to furnish the title compound as a white solid (13 mg, 12%), LC-MS (ESI) Rt 2.66 min, m/z 298 (100%, W); m/z (ESI) C13H14Cl2N3O requires 298.0508 found [M+H]+ 298.0507.

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