Phosphorus oxychloride → ethyl 4-chloro-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate

HRID 451206ノート

反応式

HRID 451206 の反応式
C(O[C:4](=O)[C:5](=[CH:11][NH:12][C:13]1[N:14]([CH2:18][CH3:19])[N:15]=[CH:16][CH:17]=1)[C:6]([O:8][CH2:9][CH3:10])=[O:7])C.O=P(Cl)(Cl)[Cl:23]>>[CH2:9]([O:8][C:6]([C:5]1[C:4]([Cl:23])=[C:17]2[CH:16]=[N:15][N:14]([CH2:18][CH3:19])[C:13]2=[N:12][CH:11]=1)=[O:7])[CH3:10]

参加物

3

反応物 2

HCID 24813Phosphorus oxychlorideHCID 12845080Diethyl {[(1-ethyl-1H-pyrazol-5-yl)amino]methylene}malonate

生成物 1

HCID 10491120ethyl 4-chloro-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate収率 69%

反応条件

温度
135 °C

実験手順

A solution of 2-[(2-ethyl-2H-pyrazol-3-ylamino)-methylene]-malonic acid diethyl ester (11.75 g, 0.041 mol) in POCl3 (70 mL) was heated at reflux (135° C.) for 8 hours. The excess of POCl3 were distilled off and the reaction mixture cooled to 0° C., before careful addition of water (100 mL) and then aqueous NaOH (3N) until pH reached 7. The product was extracted with CH2Cl2 several times, and the combined orgnic phase were dried over Na2SO4 and concentrated under vacuo. Column chromatography (SiO2, EtOAc/Heptane 1/5) afforded 7.22 g (69%) of the title product as a white solid. ES-MS m/e: 254.2 (M+H+).

後処理

  1. distillationThe excess of POCl3 were distilled off
  2. temperaturethe reaction mixture cooled to 0° C., before careful addition of water (100 mL)
  3. extractionThe product was extracted with CH2Cl2 several times
  4. dry with materialthe combined orgnic phase were dried over Na2SO4
  5. concentrationconcentrated under vacuo

出典と根拠

ORDレコード
ord-9179ab2bd5b84a39a150d267fd730d56
出典データセット
uspto-grants-2013_07
特許番号
US08487102B2

反応ノート

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