Hydrochloric Acid → ethyl 1-tert-butyl-5-chloro-1H-pyrazole-4-carboxylate

HRID 12827

反応式

HRID 12827 の反応式
N(OC(C)(C)C)=O.[CH2:8]([O:10][C:11]([C:13]1[CH:14]=[N:15][N:16]([C:19]([CH3:22])([CH3:21])[CH3:20])[C:17]=1N)=[O:12])[CH3:9].[ClH:23]>C(#N)C>[CH2:8]([O:10][C:11]([C:13]1[CH:14]=[N:15][N:16]([C:19]([CH3:22])([CH3:21])[CH3:20])[C:17]=1[Cl:23])=[O:12])[CH3:9]

参加物

5

反応物 3

HCID 313Hydrochloric AcidHCID 10906Tert-Butyl nitriteHCID 13809946ethyl 5-amino-1-(tert-butyl)-1H-pyrazole-4-carboxylate

生成物 1

HCID 13809947ethyl 1-tert-butyl-5-chloro-1H-pyrazole-4-carboxylate収率 39%

試薬・触媒・溶媒 1

HCID 6342Acetonitrile溶媒

実験手順

To a mixture of t-butyl nitrite (7.2 mL, 60.5 mmol), cuprous chloride (4.8 g, 48.5 mmol), and anhydrous acetonitrile (120 mL) was added 5-amino-1-tert-butyl-1H-pyrazole-4-carboxylic acid ethyl ester (8.4 g, 39.8 mmol) in portions over 30 minutes at 0° C. The reaction mixture was stirred at room temperature for 1 h, then at 65° C. for 1 h. The mixture was then poured into 6N HCl (120 mL) and extracted with dichloromethane. The aqueous phase was extracted three times with dichloromethane. After the combined organic phases were concentrated in vacuo, the crude residue was purified by flash chromatography eluting with a gradient of 0-20% ethyl acetate/hexanes, then 20% ethyl acetate/hexanes to give 1-tert-butyl-5-chloro-1H-pyrazole-4-carboxylic acid ethyl ester (5.5 g, 39%).

後処理

  1. waitat 65° C. for 1 h
  2. extractionextracted with dichloromethane
  3. extractionThe aqueous phase was extracted three times with dichloromethane
  4. concentrationAfter the combined organic phases were concentrated in vacuo
  5. customthe crude residue was purified by flash chromatography
  6. washeluting with a gradient of 0-20% ethyl acetate/hexanes

出典と根拠

ORDレコード
ord-04c1057d28d84cdc850db8b6d209f025
出典データセット
uspto-grants-2010_06
特許番号
US07728029B2

関連ノート

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