تفاعل #9626

معادلة التفاعل

sodium carbonate

ethyl 4-(4-bromophenyl)-2-(2-methoxyethyl)-4-oxobutanoate

4-nitro-phenyl boronic acid

→

ethyl 2-(2-methoxyethyl)-4-(4′-nitro-1,1′-biphenyl-4-yl)-4-oxobutanoate

المردود 88.0%

المذيبات

dioxane

toluene

ظروف التفاعل

المعالجة

1. 1
   أخرىTo a 150 mL 3-neck flask fitted with a reflux condenser
2. 2
   workup.ADDITIONwas added
3. 3
   أخرىof degassing
4. 4
   درجة الحرارةto cool
5. 5
   workup.ADDITIONwas diluted with ethyl acetate (75 mL) and saturated aqueous sodium chloride solution (75 mL)
6. 6
   أخرىThe layers were separated
7. 7
   استخلاصthe aqueous layer was extracted twice with ethyl acetate (50 mL)
8. 8
   غسيلthe combined organic layers were washed with saturated aqueous sodium chloride solution (75 mL)
9. 9
   تجفيفdried over anhydrous magnesium sulfate
10. 10
    ترشيحfiltered in vacuo through 2 cm Celite®/2 cm silica
11. 11
    تركيزThe filtrate was concentrated in vacuo
12. 12
    أخرىleaving a dark red-brown oil, that
13. 13
    أخرىwas purified by flash chromatography (4:1 hexane/ethyl acetate

الإجراء التجريبي

To a 150 mL 3-neck flask fitted with a reflux condenser was added ethyl 4-(4-bromophenyl)-2-(2-methoxyethyl)-4-oxobutanoate (1.06 g, 3.09 mmol) and 4-nitro-phenyl boronic acid (0.62 g, 3.70 mmol) dissolved in toluene (30 mL) and dioxane (8.50 mL), followed by addition of saturated aqueous sodium carbonate solution (8.50 mL). A thin-gauge needle was inserted into the bi-phasic mixture and degassed with argon over 30 minutes, at which point 1,2-bis[(diphenylphosphino) ferrocene] dichloropalladium(II) (0.13 g, 0.15 mmol) was added, followed by an additional 15 minutes of degassing. The reaction mixture was heated at 85° C. for 16 h, and then the resulting dark-colored reaction mixture was allowed to cool, and was diluted with ethyl acetate (75 mL) and saturated aqueous sodium chloride solution (75 mL). The layers were separated, the aqueous layer was extracted twice with ethyl acetate (50 mL), and the combined organic layers were washed with saturated aqueous sodium chloride solution (75 mL), dried over anhydrous magnesium sulfate, and filtered in vacuo through 2 cm Celite®/2 cm silica. The filtrate was concentrated in vacuo, leaving a dark red-brown oil, that was purified by flash chromatography (4:1 hexane/ethyl acetate, then 3:1 hexane/ethyl acetate, then 2:1 hexane/ethyl acetate) to afford ethyl 2-(2-methoxyethyl)-4-(4′-nitro-1,1′-biphenyl-4-yl)-4-oxobutanoate (1.04 g, 88%). LC-MS ret. time 3.38 min, m/z 385.9 (MH+); 1H NMR (300 MHz, CDCl3) δ 1.27 (t, 3H), 1.80–1.95 (m, 1H), 1.95–2.10 (m, 1H), 3.10–3.25 (m, 2H), 3.40–3.58 (m, 3H), 4.17 (q, 2H), 7.67–7.82 (2d, 4H), 8.10 (d, 2H), 8.33 (d, 2H).

المصدر