Water → 1,5-Dimethyl-3-ethoxycarbonylpyrazole

HRID 1452081

反応式

HRID 1452081 の反応式
O=[C:2]([CH2:8][C:9](=O)[CH3:10])[C:3]([O:5][CH2:6][CH3:7])=[O:4].[CH3:12][NH:13][NH2:14].C(OCC)(=O)C.O>C(O)(=O)C>[CH2:6]([O:5][C:3]([C:2]1[CH:8]=[C:9]([CH3:10])[N:13]([CH3:12])[N:14]=1)=[O:4])[CH3:7]

参加物

6

反応物 4

HCID 962WaterHCID 6061MethylhydrazineHCID 8857Ethyl AcetateHCID 69208Ethyl 2,4-dioxovalerate

生成物 1

HCID 1385771,5-Dimethyl-3-ethoxycarbonylpyrazole

試薬・触媒・溶媒 1

HCID 176Acetic Acid溶媒

実験手順

Ethyl 2,4-dioxovalerate (5.6 ml, 40 mM) was dissolved in glacial acetic acid (35 ml) before cooling the reaction temperature to 8°-10° C. Methylhydrazine (2.0 ml, 38 mM) was added dropwise so that the reaction temperature did not rise above 15° C. After stirring at room temperature for 90 minutes the reaction was poured into ethyl acetate and water. The organic phase was washed with saturated sodium bicarbonate solution, water and brine before drying (MgSO4). Purification was accomplished was by chromatography on silica gel (10×4.5 cm) loading in dichloromethane and eluting with 50% ethyl acetate in hexane. Evaporation of solvent gave the title compound as a coloured oil which crystallised on standing (4.69 g); νmax (CH2Cl2) 1717 and 1223 cm-1 ; δH (CDCl3) 1.39 (3H, t, J 7.13 Hz), 2.30 (3H, s), 3.85 (3H, s), 4.39 (2H, q, J 7.21 Hz), 6.57 (1H, s); E.I m/e 168 (25% ).

後処理

  1. temperaturebefore cooling the reaction temperature to 8°-10° C
  2. customdid not rise above 15° C
  3. washThe organic phase was washed with saturated sodium bicarbonate solution, water and brine
  4. dry with materialbefore drying (MgSO4)
  5. customPurification
  6. washeluting with 50% ethyl acetate in hexane
  7. customEvaporation of solvent

出典と根拠

ORDレコード
ord-b71efcf5e9aa4651bd33ef6c61d6e0b4
出典データセット
uspto-grants-1997_02
特許番号
US05606051

関連ノート

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