Acetaldehyde → (3S,4R)-1-(t-butyldimethylsilyl)3-[(R)-1-hydroxyethyl]-4-[2,2,2-tri(methylthio)ethyl]azetidin-2-one

HRID 648682ノート

反応式

HRID 648682 の反応式
C([Li])CCC.C(NC(C)C)(C)C.[Si:13]([N:20]1[C@H:23]([CH2:24][C:25]([S:30][CH3:31])([S:28][CH3:29])[S:26][CH3:27])[CH2:22][C:21]1=[O:32])([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14].[CH:33](=[O:35])[CH3:34]>O1CCCC1>[Si:13]([N:20]1[C@H:23]([CH2:24][C:25]([S:28][CH3:29])([S:26][CH3:27])[S:30][CH3:31])[C@@H:22]([C@H:33]([OH:35])[CH3:34])[C:21]1=[O:32])([C:16]([CH3:17])([CH3:19])[CH3:18])([CH3:15])[CH3:14]

参加物

6

反応物 4

HCID 177AcetaldehydeHCID 7912DiisopropylamineHCID 13003464(4S)-1-(t-butyldimethylsilyl)-4-(2,2,2-tri(methylthio)ethyl)azetidin-2-oneHCID 178418339Butyllithium

生成物 1

HCID 13104625(3S,4R)-1-(t-butyldimethylsilyl)3-[(R)-1-hydroxyethyl]-4-[2,2,2-tri(methylthio)ethyl]azetidin-2-one収率 50.4%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒2 回

反応条件

温度
-78 °C

実験手順

n-Butyllithium (14.8 ml of 2.5N hexane solution, 37.0 mmol) is added by syringe to a solution of diisopropylamine (3.74 g, 37.0 mmol) in 180 ml of freshly distilled tetrahydrofuran at -78° C. The resulting solution is stirred at -78° C. for 15 min prior to the addition of a solution of (4S)-1-(t-butyldimethylsilyl)-4-[2,2,2-tri(methylthio)ethyl]azetidin-2-one (12.34 g, 35.16 mmol) in 35 ml of tetrahydrofuran. This solution is stirred at -78° C. for 10 min prior to the addition of acetaldehyde (4.62 g, 105 mmol). The solution is stirred for an additional 5 min. at -78° C. and then quenched by addition of saturated aqueous ammonium chloride solution, and allowed to warm to room temperature. The mixture is poured into 250 ml of ether and washed with water (2×100 ml) and brine and dried over magnesium sulfate. Removal of solutions in vacuo gives an oil which is chromatographed on a silica gel column (1:1 ether:petroleum ether) to give (3S, 4R)-1-(t-butyldimethylsilyl)-3-[(R)-1-hydroxyethyl]-4-[2,2,2-tri(methylthio)ethyl]azetidin-2-one (7.0 g, 50.4%) at Rf =0.2. The product can be recrystallized from petroleum ether. Alternatively, the trans R product can be isolated from the crude reaction mixture by direct crystallization from a petroleum ether solution.

後処理

  1. stirringThis solution is stirred at -78° C. for 10 min
  2. stirringThe solution is stirred for an additional 5 min. at -78° C.
  3. customquenched by addition of saturated aqueous ammonium chloride solution
  4. temperatureto warm to room temperature
  5. additionThe mixture is poured into 250 ml of ether
  6. washwashed with water (2×100 ml) and brine
  7. dry with materialdried over magnesium sulfate
  8. customRemoval of solutions in vacuo
  9. customgives an oil which
  10. customis chromatographed on a silica gel column (1:1 ether:petroleum ether)

出典と根拠

ORDレコード
ord-4438622ce1e649c8804907eb8b5408f0
出典データセット
uspto-grants-1988_04
特許番号
US04736025

反応ノート

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