Ethyl bromoacetate → Ethyl 3-acetyl-4-oxopentanoate
Reaktionsgleichung
[CH3:1][C:2](=[O:7])[CH2:3][C:4](=[O:6])[CH3:5].[H-].[Na+].[CH2:10]([O:12][C:13](=[O:16])[CH2:14]Br)[CH3:11]>O1CCCC1>[CH2:10]([O:12][C:13](=[O:16])[CH2:14][CH:3]([C:2](=[O:7])[CH3:1])[C:4](=[O:6])[CH3:5])[CH3:11]Komponenten
5
Edukt 3
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
Add pentane-2,4-dione (2.0 g, 20.6 mmol) in tetrahydrofuran (30 mL) to a chilled (0° C.) suspension of 60% sodium hydride (0.99 g, 24.7 mmol) in tetrahydrofuran (40 mL). Stir for 1 hr. Then add bromoacetic acid ethyl ester (2.73 mL, 24.7 mmol) in tetrahydrofuran (30 mL) dropwise. Stir at 0° C. to room temperature for 16 hr. Partition between diethyl ether (100 mL) and saturated aqueous ammonium chloride solution (50 mL). Separate organic layer, dry (sodium sulfate), filter, concentrate and purify (silica gel chromatography, eluting with 9:1 hexanes:ethyl acetate), to give 3-acetyl-4-oxopentanoic acid ethyl ester (3.34 g, 94%). 1H NMR (CDCl3) δ 5.15 (q, 2H), 5.1 (t, 1H), 2.84 (d, 2H), 2.23 (s, 6H), 1.22 (t, 3H).