Ozone → alpha-[4-Acetylthio-3-phthalimido-2-oxoazetidin-1-yl]-alpha-acetylacetic acid
Reaction equation
[C:1]([S:4][CH:5]1[N:8]([CH:9]([C:13]([CH3:15])=C)[C:10]([OH:12])=[O:11])[C:7](=[O:16])[CH:6]1[N:17]1[C:21](=[O:22])[C:20]2=[CH:23][CH:24]=[CH:25][CH:26]=[C:19]2[C:18]1=[O:27])(=[O:3])[CH3:2].[O:28]=[O+][O-]>CO>[C:1]([S:4][CH:5]1[N:8]([CH:9]([C:13](=[O:28])[CH3:15])[C:10]([OH:12])=[O:11])[C:7](=[O:16])[CH:6]1[N:17]1[C:18](=[O:27])[C:19]2=[CH:26][CH:25]=[CH:24][CH:23]=[C:20]2[C:21]1=[O:22])(=[O:3])[CH3:2]Participants
4
Procedure
To a solution of α-[4-acetylthio-3-phthalimido-2-oxo-azetidin-1-yl]-α-isopropenyl acetic acid (100 mg) in methanol (10 ml) at 0° C. is introduced excess ozone. After the gas at the outlet makes a potassium iodide starch paper coloured, the reaction mixture is bubbled with sulfur dioxide gas. The reaction mixture is concentrated, and the obtained residue is dissolved in aqueous solution of sodium hydrogen carbonate, washed with ether, neutralized with hydrochloric acid, and extracted with methylene chloride. The extract solution is washed with water, dried, and evaporated to give α-[4-acetylthio-3-phthalimido-2-oxoazetidin-1-yl]-α-acetyl-acetic acid (64 mg). Yield: 63%. Foam. IR: νmaxCHCl3 1780, 1730, 1680 cm-1.