反応 #42351

反応方程式

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

chloride

n-butyllithium

1-ethoxylmethylimidazole

→

title compound

Methyl 3-[(dipropylamino)carbonyl]-5-[1-(ethoxymethyl)-1H-imidazol-2-yl]benzoate

溶媒

ethyl acetate

diethyl ether

tetrahydrofuran

反応条件

後処理

1. 1
   温度The reaction mixture is heated
2. 2
   温度at reflux for 2 h
3. 3
   洗浄washed with water, and brine
4. 4
   乾燥dried (sodium sulfate)
5. 5
   ろ過filtered
6. 6
   濃縮concentrated under reduced pressure
7. 7
   その他Purification by flash column chromatography (silica gel, 1-5% methanol/methylene chloride)

実験手順

To a −70° C. stirred solution of 1-ethoxylmethylimidazole (J. Am. Chem. Soc. 1978, 100, 3918) (420 mg, 3.3 mmol) in tetrahydrofuran (10 mL) is added n-butyllithium (1.6 M in hexanes, 2.3 mL, 3.6 mmol). After 30 min, zinc. chloride (9.9 mL of a 1 M solution in diethyl ether, 9.9 mmol) is added and the reaction mixture is warmed to 0° C. for 1 h. To this mixture is then added methyl 3-[(dipropylamino)carbonyl]-5-iodobenzoate (1.17 g, 3 mmol) followed by palladium(0)tetrakis(triphenylphosphine) (173 mg, 0.15 mmol). The reaction mixture is heated at reflux for 2 h. The reaction mixture is diluted with ethyl acetate (50 mL)), washed with water, and brine, dried (sodium sulfate), filtered, and concentrated under reduced pressure. Purification by flash column chromatography (silica gel, 1-5% methanol/methylene chloride) provides the title compound in pure form. 1H NMR (300 MHz, CDCl3) δ 8.52 (s, 1H), 8.10 (s, 1H), 8.03 (s, 1H), 8.19 (s, 2H), 5.28 (s, 2H), 3.95 (s, 3H), 3.59 (q, J=7 Hz, 2H), 3.49 (m, 2H), 3.21 (m, 2H), 1.70 (m, 2H), 1.54 (m, 2H), 1.25 (t, J=7 Hz, 3H), 0.99 (m, 3H), 0.75 (m, 3H).

出典