Dimethyl Sulfoxide → methyl 1-(2-oxoethyl)-1H-indazole-7-carboxylate

HRID 2168557ノート

反応式

HRID 2168557 の反応式
C(Cl)(=O)C(Cl)=O.CS(C)=O.[OH:11][CH2:12][CH2:13][N:14]1[C:22]2[C:17](=[CH:18][CH:19]=[CH:20][C:21]=2[C:23]([O:25][CH3:26])=[O:24])[CH:16]=[N:15]1>C(Cl)Cl>[O:11]=[CH:12][CH2:13][N:14]1[C:22]2[C:17](=[CH:18][CH:19]=[CH:20][C:21]=2[C:23]([O:25][CH3:26])=[O:24])[CH:16]=[N:15]1

参加物

5

反応条件

温度
-78 °C

実験手順

Oxalyl chloride (1.3 mL, 15.5 mmol) was added dropwise to a mixture of dimethyl sulfoxide (1.8 mL, 25.8 mmol) and methylene chloride (4 mL) at −78° C. After addition was complete, the mixture was stirred at −78° C. for 30 min. A solution of methyl 1-(2-hydroxyethyl)-1H-indazole-7-carboxylate (2.8 g, 12.9 mmol) from Step D above in methylene chloride (40 mL) and added dropwise while maintaining the temperature at −78° C. The reaction was then stirred at −78° C. for 1-2 h. The reaction was quenched with N,N-diisopropylethylamine, cooled to 0° C., and sat. NaHCO3 was added. The aqueous phase was extracted several times with methylene chloride and the combined organic layers were dried (Na2SO4), filtered and concentrated to give methyl 1-(2-oxoethyl)-1H-indazole-7-carboxylate as a yellow oil (3.8 g, crude): 1H NMR (300 MHz, CDCl3) δ 9.79 (s, 1H), 8.16 (s, 1H), 8.14-8.08 (m, 2H), 7.98 (d, J=7.5 Hz, 1H), 5.61 (s, 2H), 3.99 (s, 3H); MS (ESI+) m/z 219 (M+H).

後処理

  1. additionAfter addition
  2. temperaturewhile maintaining the temperature at −78° C
  3. stirringThe reaction was then stirred at −78° C. for 1-2 h
  4. customThe reaction was quenched with N,N-diisopropylethylamine
  5. temperaturecooled to 0° C.
  6. additionsat. NaHCO3 was added
  7. extractionThe aqueous phase was extracted several times with methylene chloride
  8. dry with materialthe combined organic layers were dried (Na2SO4)
  9. filtrationfiltered
  10. concentrationconcentrated

出典と根拠

ORDレコード
ord-e98462d3c9e94f03b7e2dae00f29f07f
出典データセット
uspto-grants-2015_06
特許番号
US09045501B2

反応ノート

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