Ethyl bromoacetate → Ethyl 3-acetyl-4-oxopentanoate

HRID 220456

反応式

HRID 220456 の反応式
[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]

参加物

5

反応物 3

HCID 7748Ethyl bromoacetateHCID 24758Sodium hydrideHCID 31261Acetylacetone

生成物 1

HCID 87820Ethyl 3-acetyl-4-oxopentanoate収率 94%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒3 回

実験手順

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).

後処理

  1. temperaturea chilled
  2. stirringStir at 0° C. to room temperature for 16 hr
  3. customPartition between diethyl ether (100 mL) and saturated aqueous ammonium chloride solution (50 mL)
  4. dry with materialSeparate organic layer, dry (sodium sulfate)
  5. filtrationfilter
  6. concentrationconcentrate
  7. custompurify
  8. wash(silica gel chromatography, eluting with 9:1 hexanes:ethyl acetate)

出典と根拠

ORDレコード
ord-470d29832e0b4449b6e113eba46b2f63
出典データセット
uspto-grants-2012_06
特許番号
US08202873B2

関連ノート

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