Acetic Acid → Ethyl 3-oxo-2-(2,5-dimethoxyphenylmethylidene)butanoate

HRID 233586

反応式

HRID 233586 の反応式
[CH3:1][O:2][C:3]1[CH:10]=[CH:9][C:8]([O:11][CH3:12])=[CH:7][C:4]=1[CH:5]=O.[C:13]([O:19][CH2:20][CH3:21])(=[O:18])[CH2:14][C:15]([CH3:17])=[O:16].C(O)(=O)C>C1(C)C=CC=CC=1>[O:16]=[C:15]([CH3:17])[C:14](=[CH:5][C:4]1[CH:7]=[C:8]([O:11][CH3:12])[CH:9]=[CH:10][C:3]=1[O:2][CH3:1])[C:13]([O:19][CH2:20][CH3:21])=[O:18]

参加物

5

反応物 3

HCID 176Acetic AcidHCID 8868Ethyl AcetoacetateHCID 667262,5-Dimethoxybenzaldehyde

生成物 1

HCID 53919323Ethyl 3-oxo-2-(2,5-dimethoxyphenylmethylidene)butanoate収率 76.7%

試薬・触媒・溶媒 1

HCID 1140Toluene溶媒

実験手順

A stirred solution of 25.0 grams (0.15 mole) of 2,5-dimethoxybenzaldehyde, 22.0 grams (0.17 mole) of ethyl acetoacetate, 2 mL of pipeddine, and 3 mL of glacial acetic acid in about 250 mL of toluene is placed in a reaction vessel equipped with a Dean-Stark trap, and heated at reflux for about 12 hours. After this time, the reaction mixture is cooled and washed in turn with water, a cold solution of aqueous 10% hydrochloric acid, aqueous 5% sodium bicarbonate, and aqueous 1% acetic acid. The organic layer is dried with magnesium sulfate and filtered. The filtrate is concentrated under reduced pressure to a residue. The residue is subjected to column chromatography on silica gel. Elution is accomplished using methylene chloride The column chromatography does not provide product purification as expected. The fractions are recombined and concentrated under reduced pressure to a residual oil. The oil is distilled under vacuum, yielding 32 grams of impure ethyl 3-oxo-2-(2,5-dimethoxyphenylmethylidene)butanoate. The NMR spectrum is consistent with the proposed structure.

後処理

  1. customequipped with a Dean-Stark trap
  2. temperatureheated
  3. temperatureat reflux for about 12 hours
  4. temperatureAfter this time, the reaction mixture is cooled
  5. washwashed in turn with water
  6. dry with materialThe organic layer is dried with magnesium sulfate
  7. filtrationfiltered
  8. concentrationThe filtrate is concentrated under reduced pressure to a residue
  9. washElution
  10. customdoes not provide
  11. customproduct purification
  12. concentrationconcentrated under reduced pressure to a residual oil
  13. distillationThe oil is distilled under vacuum

出典と根拠

ORDレコード
ord-5ef13e10981340468385b2f0c033bc0d
出典データセット
uspto-grants-1997_01
特許番号
US05593998

関連ノート

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