Phosphorus oxychloride → ethyl 6-chloro-1H-pyrazolo(3,4-b)pyridine-4-carboxylate

HRID 82021ノート

反応式

HRID 82021 の反応式
[CH2:1]([O:3][C:4]([C:6]1[C:7]2[CH:15]=[N:14][NH:13][C:8]=2[N:9]=[C:10](O)[CH:11]=1)=[O:5])[CH3:2].P(Cl)(Cl)([Cl:18])=O>>[CH2:1]([O:3][C:4]([C:6]1[C:7]2[CH:15]=[N:14][NH:13][C:8]=2[N:9]=[C:10]([Cl:18])[CH:11]=1)=[O:5])[CH3:2]

参加物

3

反応物 2

HCID 24813Phosphorus oxychlorideHCID 178469358ethyl 6-oxo-1,2-dihydropyrazolo[3,4-b]pyridine-4-carboxylate

生成物 1

HCID 86678157ethyl 6-chloro-1H-pyrazolo(3,4-b)pyridine-4-carboxylate収率 21%

反応条件

温度
110 °C

実験手順

A mixture of 6-hydroxy-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid ethyl ester (116.4 g, 0.562 mol) and phosphorus oxychloride (500 mL) was heated at 110° C. for 6 hours then cooled to room temperature before being evaporated under reduced pressure. The residue was taken up in EtOAc and the precipitate filtered. The filtrate was neutralized using triethylamine (500 mL) and the resulting salt filtered. The filtrate was concentrated under vacuum and the residue subjected to silica gel column chromatography using a 9/1 mixture of toluene/EtOAc to afford the title compound as a yellow solid (26.3 g, 21%).

後処理

  1. temperaturethen cooled to room temperature
  2. custombefore being evaporated under reduced pressure
  3. filtrationthe precipitate filtered
  4. filtrationthe resulting salt filtered
  5. concentrationThe filtrate was concentrated under vacuum
  6. additiona 9/1 mixture of toluene/EtOAc

出典と根拠

ORDレコード
ord-2e142686eb7b43f5b7fabf52ef3aa8ed
出典データセット
uspto-grants-2014_09
特許番号
US08846712B2

反応ノート

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