Dimethylformamide → 1,2-Dimethyl 4-oxo-2-cyclopentene-1,2-dicarboxylate

HRID 1443444ノート

反応式

HRID 1443444 の反応式
[CH3:1][O:2][C:3]([C@@H:5]1[CH2:9][C:8](=[O:10])[CH2:7][C@@H:6]1[C:11]([O:13][CH3:14])=[O:12])=[O:4].C([O-])([O-])=O.[Ca+2].CN(C=O)C>C1COCC1>[CH3:14][O:13][C:11]([CH:6]1[CH2:7][C:8](=[O:10])[CH:9]=[C:5]1[C:3]([O:2][CH3:1])=[O:4])=[O:12]

参加物

5

反応物 3

HCID 6228DimethylformamideHCID 10112Calcium CarbonateHCID 108996331,2-dimethyl (1R,2S)-4-oxocyclopentane-1,2-dicarboxylate

生成物 1

HCID 591654631,2-Dimethyl 4-oxo-2-cyclopentene-1,2-dicarboxylate

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

反応条件

温度
90 °C

実験手順

(1R,2S)-4-oxo-cyclopentane-1,2-dicarboxylic acid dimethyl ester (4.8 g, 23.8 mmol) and CuBr2 (11.9 g, 53.2 mmol) were dissolved in dry THF (70 mL) and the mixture was refluxed for two hours at 90° C. The formed CuBr was filtrated off and the organic phase was concentrated. CaCO3 (2.7 g, 27.2 mmol) and DMF (70 mL) were added and the mixture was held at 100° C. for one hour. The dark brown mixture was poured over ice (35 g) and the formed precipitate was filtrated off. The aqueous layer was extracted with ethyl acetate (1×300 mL+3×150 mL). The organic phases were dried, filtrated and concentrated. Purification by flash chromatography (toluene/EtOAc 9:1) gave 2 (2.1 g, 45%) as yellow crystals

後処理

  1. filtrationThe formed CuBr was filtrated off
  2. concentrationthe organic phase was concentrated
  3. filtrationthe formed precipitate was filtrated off
  4. extractionThe aqueous layer was extracted with ethyl acetate (1×300 mL+3×150 mL)
  5. customThe organic phases were dried
  6. filtrationfiltrated
  7. concentrationconcentrated
  8. customPurification by flash chromatography (toluene/EtOAc 9:1)
  9. customgave 2 (2.1 g, 45%) as yellow crystals

出典と根拠

ORDレコード
ord-51a9bfcfc15649688c7f1ce209401b87
出典データセット
uspto-grants-2010_02
特許番号
US07659245B2

反応ノート

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