Pyridine → 2-[(3S,4R)-4-acetylthio-3-methoxy-2-oxoazetidin-1-yl]-3-methylcrotonic acid 2,2,2-trichloroethyl ester

HRID 1710243Notes

Reaction equation

HRID 1710243 reaction equation
COC(=O)C([N:6]1[C@H:9]([S:10][C:11](=[O:13])[CH3:12])[C@@H:8]([O:14][C:15](=O)COC2C=CC=CC=2)[C:7]1=[O:25])=O.[Cl:27][C:28]([Cl:38])([Cl:37])[CH2:29][O:30][C:31](=[O:36])[CH:32]=[C:33]([CH3:35])[CH3:34].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.N1C=CC=CC=1>C(OC(=O)C)(=O)C.C(O)(=O)C>[Cl:27][C:28]([Cl:37])([Cl:38])[CH2:29][O:30][C:31](=[O:36])[C:32]([N:6]1[C@H:9]([S:10][C:11](=[O:13])[CH3:12])[C@@H:8]([O:14][CH3:15])[C:7]1=[O:25])=[C:33]([CH3:35])[CH3:34]

Participants

7

Reactant 4

HCID 1049PyridineHCID 11776TriphenylphosphineHCID 56633453(3S,4R)-2-(4-acetylthio-3-phenoxyacetoxy-2-oxoazetidin-1-yl)-2-oxoacetic acid methyl esterHCID 713631882,2,2-Trichloroethyl 3-methylbut-2-enoate

Product 1

HCID 867417812-[(3S,4R)-4-acetylthio-3-methoxy-2-oxoazetidin-1-yl]-3-methylcrotonic acid 2,2,2-trichloroethyl ester

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolventHCID 7918Acetic AnhydrideSolvent

Procedure

A solution of 3.26 g of 2- (3S,4R)-4-(benzthiazol-2-yldithio]-3-methoxy-2-oxoazetidin-1-yl]-3-methyl-crotonic acid 2,2,2-trichloroethyl ester in 36.3 ml of acetic anhydride and 12.4 ml of acetic acid is cooled to -15° and 1.7 g of triphenylphosphine are added. After stirring under nitrogen at the same temperature for 75 minutes, 24.8 ml of pyridine are added to the mixture. After stirring for a further 3 hours at 0°, the reaction mixture is concentrated by evaporation under reduced pressure and the resulting residue is purified by chromatography over silica gel with toluene and toluene/ethyl acetate (19:1). IR spectrum (in methylene chloride): characteristic absorption bands at 3.40, 5.63, 5.77, 5.80, 6.13, 7.25, 7.35, 8.26, 9.0, 9.52 and 11.90 μ.

Workup

  1. stirringAfter stirring for a further 3 hours at 0°
  2. concentrationthe reaction mixture is concentrated by evaporation under reduced pressure
  3. customthe resulting residue is purified by chromatography over silica gel with toluene and toluene/ethyl acetate (19:1)
  4. customIR spectrum (in methylene chloride): characteristic absorption bands at 3.40, 5.63, 5.77, 5.80, 6.13, 7.25, 7.35, 8.26, 9.0, 9.52 and 11.90 μ

Sources & evidence

ORD record
ord-787b8d76024843eb8f2d056c844d1aff
Source dataset
uspto-grants-1990_08
Patent number
US04952690

Reaction notes

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