Methylhydrazine → ethyl 2-(1,3,5-trimethyl-1H-pyrazol-4-yl)acetate

HRID 220457

反応式

HRID 220457 の反応式
[CH2:1]([O:3][C:4](=[O:13])[CH2:5][CH:6]([C:10](=O)[CH3:11])[C:7](=O)[CH3:8])[CH3:2].[CH3:14][NH:15][NH2:16]>C(O)(=O)C>[CH2:1]([O:3][C:4](=[O:13])[CH2:5][C:6]1[C:10]([CH3:11])=[N:16][N:15]([CH3:14])[C:7]=1[CH3:8])[CH3:2]

参加物

4

反応物 2

HCID 6061MethylhydrazineHCID 87820Ethyl 3-acetyl-4-oxopentanoate

生成物 1

HCID 16394807ethyl 2-(1,3,5-trimethyl-1H-pyrazol-4-yl)acetate収率 73.2%

試薬・触媒・溶媒 1

HCID 176Acetic Acid溶媒

実験手順

Dissolve 3-acetyl-4-oxopentanoic acid ethyl ester (3.35 g, 19.5 mmol) in glacial acetic acid (20 mL) and add methylhydrazine (1.13 mL, 21.4 mmol) dropwise. Stir the resulting mixture at room temperature for 16 hr. Concentrate and partition the residue between ethyl acetate (100 mL) and saturated aqueous sodium bicarbonate solution (50 mL). Separate organic layer, dry (sodium sulfate), filter, concentrate and purify (silica gel chromatography, eluting with 7:3 hexanes:ethyl acetate) to give (1,3,5-trimethyl-1H-pyrazol-4-yl)-acetic acid ethyl ester (2.8 g, 73%) as an oil. 1H NMR (CDCl3) δ 4.08 (q, 2H), 3.67 (s, 3H), 3.29 (s, 2H), 2.18 (s, 6H), 1.21 (t, 3H).

後処理

  1. concentrationConcentrate
  2. custompartition the residue between ethyl acetate (100 mL) and saturated aqueous sodium bicarbonate solution (50 mL)
  3. dry with materialSeparate organic layer, dry (sodium sulfate)
  4. filtrationfilter
  5. concentrationconcentrate
  6. custompurify
  7. wash(silica gel chromatography, eluting with 7:3 hexanes:ethyl acetate)

出典と根拠

ORDレコード
ord-2d95a319eeab4885851635057c0e2465
出典データセット
uspto-grants-2012_06
特許番号
US08202873B2

関連ノート

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