반응 #56556

반응 방정식

2,2,2-trichloroethyl 2-methyl-7-amino-3-cephem-4-carboxylate hydrochloride

trimethylsilylacetamide

methylene chloride

3-oxo-4-bromobutyryl bromide

→

2,2,2-trichloroethyl 2-methyl-7-(3 -oxo-4-bromobutyramido)-3-cephem-4-carboxylate

용매

water

carbon tetrachloride

반응 조건

후처리

1. 1
   온도thus obtained solution was cooled to -15° C
2. 2
   온도under cooling to -15° C.
3. 3
   workup.STIRRINGthe mixture was stirred for 1.5 hours at the same temperature and for 30 minutes without external cooling
4. 4
   기타the organic layer was separated
5. 5
   세척The organic layer was washed with 2 N hydrochloric acid (8 ml×3) and water (10 ml×2) in turn
6. 6
   건조dried over magnesium sulfate
7. 7
   여과filtered
8. 8
   농축The filtrate was concentrated under reduced pressure
9. 9
   여과collected by filtration
10. 10
    기타dried

실험 절차

A mixture of 2,2,2-trichloroethyl 2-methyl-7-amino-3-cephem-4-carboxylate hydrochloride (0.38 g.), trimethylsilylacetamide (1.1 g.) and methylene chloride (10 ml.) was stirred for 30 minutes at room temperature, and thus obtained solution was cooled to -15° C. To the solution was added dropwise 3-oxo-4-bromobutyryl bromide (1.0 m mole) in carbon tetrachloride (13 ml.) under cooling to -15° C., and the mixture was stirred for 1.5 hours at the same temperature and for 30 minutes without external cooling. The mixture was poured into cold water, and then the organic layer was separated therefrom. The organic layer was washed with 2 N hydrochloric acid (8 ml×3) and water (10 ml×2) in turn, dried over magnesium sulfate and then filtered. The filtrate was concentrated under reduced pressure. The residue was pulverized in diisopropyl ether, collected by filtration and then dried to give pale brown powder of 2,2,2-trichloroethyl 2-methyl-7-(3 -oxo-4-bromobutyramido)-3-cephem-4-carboxylate (0.31 g), mp 78° to 83° C. (dec.).

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