反应详情

温度

-50 °C

A solution of trifluoroacetic anhydride (2.12 ml) in methylene chloride (5 ml) was added dropwise to a solution of dimethyl sulfoxide (1.56 g) in methylene chloride (10 ml) at -50° C. The mixture was stirred at -50° C. for 10 minutes. To the mixture was added a solution of benzhydryl 7-formamido-3-hydroxycepham-4-carboxylate (4.12 g) in methylene chloride (10 ml) and dimethyl sulfoxide (1 ml). The mixture was stirred at -50° C. for 30 minutes and triethylamine (4 ml) was added dropwise thereto at -50° C. The reaction mixture was allowed to warm up to ambient temperature, poured into ice-water and extracted with methylene chloride. The extract was washed three times with water, dried over magnesium sulfate and filtered, and the filtrate was evaporated in vacuo The residue was triturated with diisopropyl ether to give benzhydryl 7-formamido-3-hydroxy-3-cephem-4-carboxylate (3.42 g) as powder.

1. stirringThe mixture was stirred at -50° C. for 30 minutes
2. customat -50° C
3. temperatureto warm up to ambient temperature
4. extractionextracted with methylene chloride
5. washThe extract was washed three times with water
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. customthe filtrate was evaporated in vacuo The residue
9. customwas triturated with diisopropyl ether