反应详情

To a suspension of tetrabutylammonium bromide (322 mg, 1 mmole) and potassium hydroxide (85%, 70 mg, 1.1 mmole) in dichloromethane (10 ml) cooled to 5° was added with vigorous stirring 4-tritylthio-2-azetidinone (345 mg, 1 mmole) and methoxyethoxymethyl chloride (187 mg, 1.5 mmole). The mixture was stirred at room temperature for 2 h, the solvent was evaporated and the residue partitioned between water and ethyl acetate. The dried organic phase was concentrated to leave a viscous oil (415 mg). Purification by column chromatography on silica gel eluting with ether (5%)-dichloromethane gave the title compound (206 mg, 48%) as an oil. δ (ppm, CDCl3): 7.30 (15H, m, aromatics), 4.57 (2H, AB quartet, N--CH2O), 4.46 (1H, dd, H-4), 3.50 (4H, s, OCH2CH2O), 3.30 (3H, s, CH3), 2.75 ( 2H, m, H-3).

1. temperaturecooled to 5°
2. additionwas added
3. customthe solvent was evaporated
4. customthe residue partitioned between water and ethyl acetate
5. concentrationThe dried organic phase was concentrated