反应详情

To a solution of methyl (4-benzylthio-2-oxo-azetidin-1-yl)acetate (2.5 g, 9.4 mmol) in methanol (80 ml) was added, dropwise at 0° C., a solution of 1 N sodium hydroxide (9.9 ml, 9.9 mmol). The reaction was stirred for 1 hr and evaporated to dryness. Water (50 ml) was added and the solution acidified to pH 3 with dilute hydrochloric acid and extracted with ethyl acetate (3×100 ml). The combined extracts were dried (MgSO4), evaporated and the residue purified by recrystallisation (hexane/ether) to give (4-benzylthio-2-oxo-azetidin-1-yl)acetic acid as a white solid (1.3 g, 55%), mp 110-110° C. 1H NMR δ (CDCl3) 2.99 (1H, dd, J=6.87, 17.5 Hz, H3a), 3.27, 4.06 (each 1H, d, J=18.40 Hz, NCH2), 3.39 (1H, dd, J=5, 15.4 Hz, H3b), 3.77 (2H, s, SCH2), 4.91 (1H, m, H4), 7.27 (5H, m, Ph-H).

1. customevaporated to dryness
2. additionWater (50 ml) was added
3. extractionextracted with ethyl acetate (3×100 ml)
4. dry with materialThe combined extracts were dried (MgSO4)
5. customevaporated
6. customthe residue purified by recrystallisation (hexane/ether)