반응 #56746

반응 방정식

1-[(3S)-5-hydroxy-3-(hydroxymethyl)-2,3-dihydro-1,4-benzodioxin-6-yl]-1-ethanone oxime

N,N-dimethylacetamide acetonitrile

phosphorus oxychloride

N,N-dimethylacetamide acetonitrile

sodium acetate

→

[2-Methyl-7,8-dihydro[1,4]dioxino[2,3-g][1,3]benzoxazol-8-yl]methanol

반응 조건

후처리

1. 1
   온도The solution was cooled in an ice/water bath
2. 2
   추출extracted with ethyl acetate
3. 3
   건조dried over magnesium sulfate
4. 4
   여과filtered
5. 5
   기타evaporated in vacuum
6. 6
   기타chromatographed on silica gel with 60% hexane/ethyl acetate
7. 7
   기타to remove impurities
8. 8
   세척the product eluted with 40% hexane/ethyl acetate
9. 9
   기타After evaporation of the solvent in vacuum, 2.08 g (75%) of the (S)-enantiomer of the title compound
10. 10
    기타was obtained as a white solid, m.p. 120° C

실험 절차

3.03 g (12.6 mmole) of 1-[(3S)-5-hydroxy-3-(hydroxymethyl)-2,3-dihydro-1,4-benzodioxin-6-yl]-1-ethanone oxime was dissolved in- a mixture of 1:3 N,N-dimethylacetamide/acetonitrile (100 mL). The solution was cooled in an ice/water bath and a solution of phosphorus oxychloride (1.26 mL, 35 mmole) in 1:3 N,N-dimethylacetamide/acetonitrile (30 mL) was added. The reaction mixture was stirred under nitrogen over a period of 48 hours. It was then added to an ice cold, saturated solution of sodium acetate, extracted with ethyl acetate, dried over magnesium sulfate, filtered and evaporated in vacuum. The resulting crude oil was column chromatographed on silica gel with 60% hexane/ethyl acetate to remove impurities and the product eluted with 40% hexane/ethyl acetate. After evaporation of the solvent in vacuum, 2.08 g (75%) of the (S)-enantiomer of the title compound was obtained as a white solid, m.p. 120° C. MS (ESI) m/z 222 (M+H)+.

출처