Dimethylformamide → 1,2-Dimethyl 4-oxo-2-cyclopentene-1,2-dicarboxylate
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 the title compound (2.1 g, 45%) as yellow crystals
後処理
- filtrationThe formed CuBr was filtrated off
- concentrationthe organic phase was concentrated
- filtrationthe formed precipitate was filtrated off
- extractionThe aqueous layer was extracted with ethyl acetate (1×300 ml+3×150 ml)
- customThe organic phases were dried
- filtrationfiltrated
- concentrationconcentrated
- customPurification by flash chromatography (toluene/EtOAc 9:1)
出典と根拠
- ORDレコード
- ord-bbb09f1f7b1d466fbb8647a15e939b01
- 出典データセット
- uspto-grants-2015_01
- 特許番号
- US08937080B2
反応ノート
読み込み中…