反应详情

Methyl 3-methyl-2-(2-chlorosulfinyl-4-oxo-3-phthalimido-1-azetidinyl)-3-butenoate (0.20 g.) was stirred in about 27 g. of polyphosphoric acid for 20 minutes. Ice water and ethyl acetate (25 ml.) was added to the reaction mixture. The organic layer was separated and washed successively with water, aqueous sodium bicarbonate, and brine, dried (MgSO4), and evaporated in vacuo to dryness to give methyl 7-phthalimido-3-methylenecepham-4-carboxylate 1-oxide (0.05 g.) as a white foam.

1. customThe organic layer was separated
2. washwashed successively with water, aqueous sodium bicarbonate, and brine
3. dry with materialdried (MgSO4)
4. customevaporated in vacuo to dryness