1-(1,1-Dimethylethyl) 2-ethyl (2S)-5-oxo-1,2-pyrrolidinedicarboxylate → (S)-2-tert-Butoxycarbonylamino-5-oxo-hexanoic acid ethyl ester

HRID 1504325ノート

反応式

HRID 1504325 の反応式
[CH3:1][CH2:2][O:3][C:4]([C@@H:6]1[CH2:10][CH2:9][C:8](=[O:11])[N:7]1[C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13])=[O:5].[CH3:19][Mg]Br>C1COCC1>[CH2:2]([O:3][C:4](=[O:5])[C@@H:6]([NH:7][C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13])[CH2:10][CH2:9][C:8](=[O:11])[CH3:19])[CH3:1]

参加物

4

反応物 2

HCID 54611861-(1,1-Dimethylethyl) 2-ethyl (2S)-5-oxo-1,2-pyrrolidinedicarboxylateHCID 178418573HCID 178418573、化合物

生成物 1

HCID 58544329(S)-2-tert-Butoxycarbonylamino-5-oxo-hexanoic acid ethyl ester収率 1,390.3%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

反応条件

温度
-43 °C

実験手順

A solution of (S)-5-oxo-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-ethyl ester (20 g, 10 mmol) in dry THF (150 mL) was cooled to −50° C., and then methylmagnesium bromide (31 mL, 93.28 mmol) was added dropwise at a temperature between −50 and −44° C. in 30 min. The reaction mixture was stirred at −43° C. for 2 h and placed in a freezer (ca. −20° C.) overnight. The mixture was quenched with sat. NH4Cl solution and extracted with EtOAc. The combined organic layers were dried over Na2SO4, filtered and concentrated under reduced pressure to give the crude product, which was purified by column chromatography (8:1-3:1 petroleum ether:EtOAc) to give the title intermediate (38 g) as light yellow oil. 1H NMR (400 MHz, CDCl3): δ(ppm) 5.11-5.09 (m, 1H), 4.25-4.24 (m, 1H), 4.19 (q, J=7.2 Hz, 2H), 2.63-2.52 (m, 2H), 2.15 (s, 3H), 2.12-2.08 (m, 1H), 1.92-1.82 (m, 1H), 1.44 (s, 9H), 1.28 (t, J=7.2 Hz, 3H).

後処理

  1. customplaced in a freezer (ca. −20° C.) overnight
  2. customThe mixture was quenched with sat. NH4Cl solution
  3. extractionextracted with EtOAc
  4. dry with materialThe combined organic layers were dried over Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure
  7. customto give the crude product, which
  8. customwas purified by column chromatography (8:1-3:1 petroleum ether:EtOAc)

出典と根拠

ORDレコード
ord-9b127c8b82c6494b94f6b8c7a3049a10
出典データセット
uspto-grants-2015_12
特許番号
US09212168B2

反応ノート

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