Benzene → methyl [(3R,4R)-3-benzyloxycarbonylamino-4-allyl-2-oxoazetidin-1-yl]-3-methylbut-2-enoate

HRID 1194087Notes

Reaction equation

HRID 1194087 reaction equation
[NH2:1][C@@H:2]1[C@@H:5]([CH2:6][CH:7]=[CH2:8])[N:4]([C:9]([C:13]([O:15][CH3:16])=[O:14])=[C:10]([CH3:12])[CH3:11])[C:3]1=[O:17].[CH:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1>O1CCOCC1>[CH2:16]([O:15][C:13]([NH:1][C@@H:2]1[C@@H:5]([CH2:6][CH:7]=[CH2:8])[N:4]([C:9]([C:13]([O:15][CH3:16])=[O:14])=[C:10]([CH3:12])[CH3:11])[C:3]1=[O:17])=[O:14])[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Participants

4

Reactant 2

HCID 241BenzeneHCID 14581224methyl [(3R,4R)-3-amino-4-allyl-2-oxoazetidin-1-yl]-3-methylbut-2-enoate

Product 1

HCID 14581226methyl [(3R,4R)-3-benzyloxycarbonylamino-4-allyl-2-oxoazetidin-1-yl]-3-methylbut-2-enoateYield 97%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent2×

Procedure

5.05 g (21.2 mmol) of (3R,4R)-3-amino-1-(1-methoxycarbonyl-2-methyl-1-propenyl)-4-(2-propenyl)-2-azetidinone [6] was dissolved in 30 ml of dioxane, and a dioxane solution (60 ml) of 6.4 g (23.3 mmol) of S-4,6-dimethylpyrimidin-2-ylthiocarbonate was added dropwise to the solution at room temperature. The mixture was stirred at room temperature for 16 hours. Benzene (100 ml) was added to the reaction solution, and the insoluble materials were separated by filtration. The filtrate was concentrated, and the resulting syrup was dissolved in a small amount of methylene chloride. The solution was adsorbed on a column of silicas gel (500 g), and the column was eluted stepwise with benzene and benzene/ethyl acetate (10/1, 5/1 and 3/1). Fractions in the eluates which showed a UV absorption at an Rf of 0.20 in TLC developed with benzene/ethyl acetate (4:1) were collected and concentrated under reduced pressure to give 7.66 g (97%) of the captioned compound as a colorless syrup.

Workup

  1. customthe insoluble materials were separated by filtration
  2. concentrationThe filtrate was concentrated
  3. dissolutionthe resulting syrup was dissolved in a small amount of methylene chloride
  4. washthe column was eluted stepwise with benzene and benzene/ethyl acetate (10/1, 5/1 and 3/1)
  5. customa UV absorption at an Rf of 0.20 in TLC
  6. customwere collected
  7. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-7c121911b6754ed7b14fba32e5e2f441
Source dataset
uspto-grants-1989_03
Patent number
US04812563

Reaction notes

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