4-Acetoxy-2-azetidinone → HCID 19605239, compound

Participants

Reaction Conditions

Reaction Steps

Sodium (0.9 g, 39 mmol) was dissolved in ethanol (150 ml) and 3,4-dimethoxythiophenol (5.9 g, 35 mmol) added dropwise over 20 minutes keeping the temperature between 20° C.-25° C. whilst bubbling nitrogen through the mixture. After 15 minutes, the reaction was cooled to 5° C. and a solution of 4-acetoxyazetidin-2-one (4.3 g, 33 mmol) in ethanol (50 ml) was added dropwise over 15 minutes whilst maintaining the temperature at 5° C. The mixture was stirred at room temperature for 60 minutes and evaporated to dryness under reduced pressure. Water (400 ml) was added, the mixture extracted with dichloromethane (2×300 ml), the extracts dried (MgSO4) and evaporated under reduced pressure to an oil. The oil was cooled to -20° C. and titurated with ether (400 ml) to give a white solid which was isolated by filtration (4.1 g, 52%) m.p. 145-6° C. 1H NMR δ (CDCl3) 2.85 (1H, m, H3a), 3.31 (1H, m, H3b), 3.88 (3H, s, O--CH3), 3.89 (3H, s, O--CH3), 4.92 (1H, dd, J=4.92, 2.30 Hz, H4), 6.30 (1H, br. singlet, N--H), 6.85 (1H, d, J=8.30 Hz, Ph--H), 7.00 (1H, d, J=2.04 Hz, Ph--H), 7.09 (1H, dd, J=8.25, 2.06 Hz, Ph--H).

Provenance & Evidence