| 摘要 |
PURPOSE:To obtain the present substance important as a synthetic intermediate for antimicrobial agent penems, etc., in good yield by reacting a 4- benzoyloxyazetidinone derivative with an alkaline metal salt of acetic acid in the presence of a phase-transfer catalyst in an aprotic organic solvent. CONSTITUTION:A compound expressed by formula I (R1 is protecting group of hydroxyl group; R2 is halogen, lower alkyl or lower alkoxy; n is 0-3) is reacted with an alkaline metal salt of acetic acid (preferably K salt) in the presence of a phase-transfer catalyst (e.g., tetraethylammonium chloride) in an aprotic organic solvent (preferably a solvent, such as ethyl acetate, sparingly soluble in water) at ambient temperature to afford the aimed compound expressed by formula II. A compound expressed by formula I (R1 is tert- butyldimethylsilyl; n is 0) is preferred as the compound expressed by formula I. |
