N-Ethylpiperidine → (3S,4R)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-4-[(1RS)-1-methyl-2-oxo-2-(2-thioxothiazolidin-3-yl)ethyl]-2-azetidinone

HRID 1461483Notes

Reaction equation

HRID 1461483 reaction equation
C(N1CCCCC1)C.[C:9]([N:13]1[CH2:17][CH2:16][S:15][C:14]1=[S:18])(=[O:12])[CH2:10][CH3:11].C(O[C@H:23]1[NH:26][C:25](=[O:27])[C@@H:24]1[C@H:28]([O:30][Si:31]([C:34]([CH3:37])([CH3:36])[CH3:35])([CH3:33])[CH3:32])[CH3:29])(=O)C.C(=O)(O)[O-].[Na+]>ClCCl>[Si:31]([O:30][C@@H:28]([C@@H:24]1[C@@H:23]([CH:10]([CH3:11])[C:9](=[O:12])[N:13]2[CH2:17][CH2:16][S:15][C:14]2=[S:18])[NH:26][C:25]1=[O:27])[CH3:29])([C:34]([CH3:35])([CH3:36])[CH3:37])([CH3:32])[CH3:33]

Participants

6

Conditions

Temperature
-78 °C

Procedure

To a suspension of stannous trifluoromethanesulfonate (8.35 g) and N-ethylpiperidine (3.79 ml) in dichloromethane (60 ml) was added dropwise a solution of 3-propionyl-2-thioxothiazolidine (4.12 g) in dichloromethane (35 ml) at -78° C. under nitrogen atmosphere. After stirring at -78° C. for 30 minutes, a solution of (3R,4R)-4-acetoxy-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-2-azetidinone (2.25 g) in dichloromethane (8 ml) was added to the reaction mixture, and the reaction mixture was stirred at 0° C. for 30 minutes and then at room temperature for 20 minutes. The reaction mixture was poured into aqueous sodium bicarbonate solution (100 ml) and the precipitated white mass was removed by passing through a layer of celite. The organic layer was separated and washed with 10% aqueous sodium chloride solution (100 ml×2). The organic solution was dried over magnesium sulfate and evaporated. The residue was chromatographed on silica gel (185 g) eluting with a mixture of acetone and dichloromethane (2:98, V/V) to give (3S,4R)-3-[(1R)-1-(t-butyldimethylsilyloxy)ethyl]-4-[(1RS)-1-methyl-2-oxo-2-(2-thioxothiazolidin-3-yl)ethyl]-2-azetidinone (2.39 g).

Workup

  1. stirringthe reaction mixture was stirred at 0° C. for 30 minutes
  2. waitat room temperature for 20 minutes
  3. customthe precipitated white mass was removed
  4. customThe organic layer was separated
  5. washwashed with 10% aqueous sodium chloride solution (100 ml×2)
  6. dry with materialThe organic solution was dried over magnesium sulfate
  7. customevaporated
  8. customThe residue was chromatographed on silica gel (185 g)
  9. washeluting with a mixture of acetone and dichloromethane (2:98, V/V)

Sources & evidence

ORD record
ord-44dd8d6c147848aa8ec7faf11d7b285b
Source dataset
uspto-grants-1991_12
Patent number
US05075437

Reaction notes

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