反应详情

To a solution of (3S,4S)-4-(1-chloromethylethenyl)-3-(1-(R)-benzyloxycarbonyloxyethyl)-1-di(p-anisyl)methyl-2-azetidinone (20 g) in dimethylsulfoxide (160 ml), there were successively added water (40 ml), cuprous oxide (6.76 g) and p-toluenesulfonic acid (7.6 g), and the resultant mixture was warmed to 50 to 55° C. and stirred for 2 hours at the same temperature. After cooling down to room temperature, 1% aqueous phosphoric acid (90 ml) and ethyl acetate (200 ml) were poured into the reaction mixture, followed by stirring for 0.5 hour. An insoluble material was removed by filtration over celite and washed 3 times with ethyl acetate (20 ml). The filtrate and the washings were combined together, and the aqueous layer was separated from the organic layer and extracted with ethyl acetate (200 ml). The organic layer and the extract were combined together, washed with brine and dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated in vacuo, and the concentrate was crystallized from a mixture of toluene and n-hexane (1 : 1) to give crystals of (3S,4S)-4-(1-hydroxymethylethenyl)-3-(1-(R)-benzyloxycarbonyloxyethyl)-1-di(p-anisyl)methyl-2-azetidinone. m.p., 118°-120° C.

1. stirringby stirring for 0.5 hour
2. customAn insoluble material was removed by filtration over celite
3. washwashed 3 times with ethyl acetate (20 ml)
4. customthe aqueous layer was separated from the organic layer
5. extractionextracted with ethyl acetate (200 ml)
6. washwashed with brine
7. dry with materialdried over anhydrous sodium sulfate
8. filtrationAfter filtration
9. concentrationthe filtrate was concentrated in vacuo
10. customthe concentrate was crystallized from a mixture of toluene and n-hexane (1 : 1)