Triethyl phosphite → allyl (4R,5S,6S)-6-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-methyl-3-methylthio-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate

HRID 1464727Notes

Reaction equation

HRID 1464727 reaction equation
P(OCC)(OCC)OCC.[CH2:11]([O:14][C:15](=[O:39])[C:16]([N:18]1[C@H:21]([C@H:22]([C:24]([S:26][CH3:27])=S)[CH3:23])[C@@H:20]([C@H:28]([O:30][Si:31]([C:34]([CH3:37])([CH3:36])[CH3:35])([CH3:33])[CH3:32])[CH3:29])[C:19]1=[O:38])=O)[CH:12]=[CH2:13].C(OC(=O)C(N1[C@H]([C@@H](C(SC)=S)C)[C@@H]([C@H](O[Si](C(C)(C)C)(C)C)C)C1=O)=O)C=C>C1(C)C=CC=CC=1>[Si:31]([O:30][C@@H:28]([C@H:20]1[C:19](=[O:38])[N:18]2[C@@H:21]1[C@@H:22]([CH3:23])[C:24]([S:26][CH3:27])=[C:16]2[C:15]([O:14][CH2:11][CH:12]=[CH2:13])=[O:39])[CH3:29])([C:34]([CH3:35])([CH3:37])[CH3:36])([CH3:32])[CH3:33]

Participants

5

Reactant 3

HCID 31215Triethyl phosphiteHCID 86747781(3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1R)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidineHCID 86747782(3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1S)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine

Product 1

HCID 57185440allyl (4R,5S,6S)-6-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-methyl-3-methylthio-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylateYield 13.2%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A mixture of triethyl phosphite (1.43 g), toluene (3 ml) and a mixture (1.0 g) of (3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1R)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine and (3S,4S)-1-(allyloxyoxalyl)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[(1S)-1-{(methylthio)thiocarbonyl}ethyl]-2-oxoazetidine was heated at 80° C. for 26 hours and then refluxed for 16 hours. After removal of the solvent, the residue was dissolved in hexane, washed with water, dried, and concentrated in vacuo. The oily residue was purified by silica gel column chromatography [diethyl ether-hexane (1:3, V/V)] to afford a mixture (118 mg) of allyl (4R,5S,6S)-6-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-methyl-3-methylthio-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate and allyl (4S,5S,6S)-6-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-methyl-3 -methylthio-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate.

Workup

  1. temperaturerefluxed for 16 hours
  2. customAfter removal of the solvent
  3. dissolutionthe residue was dissolved in hexane
  4. washwashed with water
  5. customdried
  6. concentrationconcentrated in vacuo
  7. customThe oily residue was purified by silica gel column chromatography [diethyl ether-hexane (1:3, V/V)]

Sources & evidence

ORD record
ord-d55ebd7ade194739b74ddbf9298093cb
Source dataset
uspto-grants-1994_04
Patent number
US05306816

Reaction notes

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