Boc-D-alanine methyl ester → tert-butyl N-((2R)-1-oxopropan-2-yl)carbamate

HRID 1037966ノート

反応式

HRID 1037966 の反応式
[C:1]([O:5][C:6]([NH:8][C@H:9]([CH3:14])[C:10](OC)=[O:11])=[O:7])([CH3:4])([CH3:3])[CH3:2].[H-].C([Al+]CC(C)C)C(C)C>C(Cl)Cl>[O:11]=[CH:10][C@H:9]([NH:8][C:6](=[O:7])[O:5][C:1]([CH3:4])([CH3:3])[CH3:2])[CH3:14]

参加物

4

反応物 2

HCID 637612Boc-D-alanine methyl esterHCID 21225700Diisobutylaluminumhydride

生成物 1

HCID 10910049tert-butyl N-((2R)-1-oxopropan-2-yl)carbamate収率 165%

試薬・触媒・溶媒 1

HCID 6344Dichloromethane溶媒

反応条件

温度
-78 °C

実験手順

To a cooled solution of (R)-methyl 2-(tert-butoxycarbonylamino)propanoate (40.0 g, 98.0 mmol) in DCM (200 mL) at −78° C. was added diisobutylaluminum hydride (208 mL, 1.0 M in THF) dropwise over 30 min. The reaction mixture was stirred at −78° C. for 1.5 h then quenched with water (50 mL). After warmed to rt, the white precipitate was removed by filtration over Celite. The organic layer was then washed with brine, dried (Na2SO4), and concentrated. The crude residue was purified by flash chromatography (petroleum ether:EtOAc, 10:1) to give (R)-tert-butyl 1-oxopropan-2-ylcarbamate (28.0 g, 82%). 1H NMR (DMSO-d6, 400 MHz) δ 9.43 (s, 1H), 7.33 (d, J=6.0 Hz, 1H), 3.85 (m, 1H), 1.39 (s, 9H), 1.12 (d, J=7.2 Hz, 3H).

後処理

  1. customthen quenched with water (50 mL)
  2. temperatureAfter warmed to rt
  3. customthe white precipitate was removed by filtration over Celite
  4. washThe organic layer was then washed with brine
  5. dry with materialdried (Na2SO4)
  6. concentrationconcentrated
  7. customThe crude residue was purified by flash chromatography (petroleum ether:EtOAc, 10:1)

出典と根拠

ORDレコード
ord-9cbc93299a524e0fad20be198954d31d
出典データセット
uspto-grants-2013_10
特許番号
US08546588B2

反応ノート

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