Sodium hydride → Methyl 5-(benzofuran-2-yl)-2,4-dimethyl-3,5-dioxopentanoate

HRID 1357192

反応式

HRID 1357192 の反応式
[H-].[Na+].[CH3:3][CH:4]([C:9](=[O:12])[CH2:10][CH3:11])[C:5]([O:7][CH3:8])=[O:6].[Li]CCCC.[O:18]1[C:22]2[CH:23]=[CH:24][CH:25]=[CH:26][C:21]=2[CH:20]=[C:19]1[C:27]([O:29]C)=O.OS([O-])(=O)=O.[K+]>C1COCC1>[O:18]1[C:22]2[CH:23]=[CH:24][CH:25]=[CH:26][C:21]=2[CH:20]=[C:19]1[C:27](=[O:29])[CH:10]([CH3:11])[C:9](=[O:12])[CH:4]([CH3:3])[C:5]([O:7][CH3:8])=[O:6]

参加物

7

反応物 5

HCID 24758Sodium hydrideHCID 291153Methyl 1-benzofuran-2-carboxylateHCID 516920Potassium bisulfateHCID 545860Methyl 2-methyl-3-oxopentanoateHCID 178418339Butyllithium

生成物 1

HCID 15462823Methyl 5-(benzofuran-2-yl)-2,4-dimethyl-3,5-dioxopentanoate

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒2 回

反応条件

温度
0 °C

実験手順

After adding 60% NaH (220 mg) to a solution of methyl 2-methyl-3-oxopentanoate (750 mg) in THF (5 ml) at 0° C. and stirring at 0° C. for 5 minutes, the mixture was cooled to −78° C. To this reaction solution there was added 1.63 M n-BuLi (3.3 ml), and the mixture was stirred at −78° C. for 30 minutes to prepare a dienolate. A solution of methyl 2-benzofurancarboxylate (300 mg) in THF (10 ml) was added to the dienolate, and the mixture was stirred at −78° C. for 20 minutes. The reaction solution was allowed to return to 0° C., aqueous KHSO4 was added for quenching, and extraction was performed with AcOEt. The organic layer was rinsed with saturated saline and dried with MgSO4, and then filtered and concentrated. The residue was crudely purified by silica gel column chromatography (n-hexane/AcOEt=3/1→2/1) to obtain methyl 5-(benzofuran-2-yl)-2,4-dimethyl-3,5-dioxopentanoate.

後処理

  1. temperaturethe mixture was cooled to −78° C
  2. stirringthe mixture was stirred at −78° C. for 30 minutes
  3. customto prepare a dienolate
  4. stirringthe mixture was stirred at −78° C. for 20 minutes
  5. customto return to 0° C.
  6. customfor quenching
  7. extractionextraction
  8. washThe organic layer was rinsed with saturated saline
  9. dry with materialdried with MgSO4
  10. filtrationfiltered
  11. concentrationconcentrated
  12. customThe residue was crudely purified by silica gel column chromatography (n-hexane/AcOEt=3/1→2/1)

出典と根拠

ORDレコード
ord-923f2329c92442bbbf8bc2efab1c0960
出典データセット
uspto-grants-2003_07
特許番号
US06589984B1

関連ノート

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