Ammonium Chloride → (3S,5R)-5-Methyl-3-((4R,5S)-4-methyl-2-oxo-5-phenyl-oxazolidine-3-carbonyl)-octanoic acid tert-butyl ester

HRID 28429ノート

反応式

HRID 28429 の反応式
[CH3:1][C@@H:2]1[C@H:6]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=2)[O:5][C:4](=[O:13])[N:3]1[C:14](=[O:22])[CH2:15][CH2:16][C@H:17]([CH3:21])[CH2:18][CH2:19][CH3:20].C[Si]([N-][Si](C)(C)C)(C)C.[Na+].[C:33]([O:37][C:38](=[O:41])[CH2:39]Br)([CH3:36])([CH3:35])[CH3:34].[Cl-].[NH4+]>C1COCC1>[C:33]([O:37][C:38](=[O:41])[CH2:39][C@@H:15]([C:14]([N:3]1[C@H:2]([CH3:1])[C@H:6]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=2)[O:5][C:4]1=[O:13])=[O:22])[CH2:16][C@H:17]([CH3:21])[CH2:18][CH2:19][CH3:20])([CH3:36])([CH3:35])[CH3:34]

参加物

6

反応物 4

HCID 25517Ammonium ChlorideHCID 79177tert-Butyl bromoacetateHCID 2724254Sodium bis(trimethylsilyl)amideHCID 57160957(4R,5S)-4-Methyl-3-((R)-4-methyl-heptanoyl)-5-phenyl-oxazolidin-2-one

生成物 1

HCID 57207445(3S,5R)-5-Methyl-3-((4R,5S)-4-methyl-2-oxo-5-phenyl-oxazolidine-3-carbonyl)-octanoic acid tert-butyl ester収率 71.8%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒2 回

反応条件

温度
-50 °C

実験手順

To (4R,5S)-4-methyl-3-((R)-4-methyl-heptanoyl)-5-phenyl-oxazolidin-2-one (12.1 g, 0.04 mol) in THF (200 ml) at −50° C. was added sodium bis(trimethylsilyl)amide (48 mL of a 1 M solution in THF). After 30 min t-butylbromoaceate (15.6 g, 0.08 mol) was added. The solution was stirred for 4 hours at −50° C. and then warmed to room temperature. After 16 hours a saturated aqueous solution of ammonium chloride was added and the two layers separated. The aqueous phase was extracted with ether and the combined organic phases dried (MgSO4) and concentrated. Flash chromatography (9:1 hexane/EtOAc) gave (3S,5R)-5-methyl-3-((4R,5S)-4-methyl-2-oxo-5-phenyl-oxazolidine-3-carbonyl)-octanoic acid tert-butyl ester as a white solid 12 g; 72%. [a]D=+30.2 (c 1 in CHCl3). 13C NMR (100 MHz; CDCl3) 176.47, 171.24, 152.72, 133.63, 128.87, 125.86, 80.85, 78.88, 55.34, 39.98, 38.77, 38.15, 37.58, 30.60, 28.23, 20.38, 20.13, 14.50, 14.28.

後処理

  1. temperaturewarmed to room temperature
  2. customthe two layers separated
  3. extractionThe aqueous phase was extracted with ether
  4. dry with materialthe combined organic phases dried (MgSO4)
  5. concentrationconcentrated

出典と根拠

ORDレコード
ord-775d6eb6009242fc9d2ebddbd03eb751
出典データセット
uspto-grants-2008_09
特許番号
US07419981B2

反応ノート

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