反応 #42571

反応方程式

2-triethylstannyloxazole

methyl 3-[(dipropylamino)carbonyl]-5-iodobenzoate

→

methyl 3-[(dipropylamino)carbonyl]-5-(1,3-oxazol-2-yl)benzoate

収率 27.8%

溶媒

dimethylformamide

反応条件

後処理

1. 1
   その他purged with argon
2. 2
   その他the reaction mixture was degassed under reduced pressure for 15 min
3. 3
   その他purged with argon
4. 4
   温度The reaction mixture was heated
5. 5
   温度at reflux for 2 d
6. 6
   workup.ADDITIONdiluted with ethyl acetate
7. 7
   洗浄washed with water (3×50 mL)
8. 8
   乾燥dried (sodium sulfate)
9. 9
   濃縮concentrated under reduced pressure
10. 10
    その他Purification by flash column chromatography (silica, 1:1 ethyl acetate/hexanes)

実験手順

A stirred solution of 2-triethylstannyloxazole (Chem. Mater. 1994, 6, 1023) (1.5 g, 5.5 mmol) and methyl 3-[(dipropylamino)carbonyl]-5-iodobenzoate (1.8 g, 4.6 mmol) in dimethylformamide (12 mL) was degassed under reduced pressure for 15 min and purged with argon. Palladium(0)tetrakis(triphenylphosphine) (158 mg, 0.14 mmol) was added and the reaction mixture was degassed under reduced pressure for 15 min and then purged with argon. The reaction mixture was heated at reflux for 2 d, cooled to room temperature, diluted with ethyl acetate, washed with water (3×50 mL), dried (sodium sulfate), and concentrated under reduced pressure. Purification by flash column chromatography (silica, 1:1 ethyl acetate/hexanes) provided methyl 3-[(dipropylamino)carbonyl]-5-(1,3-oxazol-2-yl)benzoate (423 mg): 1H NMR (300 MHz, CDCl3) δ 8.73 (s, 1H), 8.23 (s, 1H), 8.11 (s, 1H), 7.76 (s, 1H), 7.28 (s, 1H), 3.97 (s, 3H), 3.49 (br s, 2H), 3.18 (br s, 2H), 1.72 (d, J=7 Hz, 2H), 1.55 (d, J=7 Hz, 2H), 1.00 (t, J=7 Hz, 3H), 0.75 (t, J=7 Hz, 3H).

出典