反应详情

Triethylamine (0 61 g, 6.0 mmol was dropped into a solution of (3S-trans)-3-(t-butyloxy-carbonylamino)-1-hydroxy-4-methyl-2-azetidinone (1.08 g. 5.0 mmol) and diphenylmethylchloroacetate (1.43 g. 5.5 mmol) in 10 ml of dry dimethylformamide. The mixture was stirred overnight at room temperature. The precipitate was removed by filtration and the solvent was stripped in vacuo. The residue was taken up in ethyl acetate, filtered, washed with 5% NaHCO3 solution and with water, dried over MgSO4 and evaporated in vacuo to give a colorless oil; yield 2.0 g. By storing in a refrigerator the title compound crystallized, melting point 73°-74° C.

1. customThe precipitate was removed by filtration
2. filtrationfiltered
3. washwashed with 5% NaHCO3 solution and with water
4. dry with materialdried over MgSO4
5. customevaporated in vacuo
6. customto give a colorless oil