1,2-Dibromoethane → 2,3-dihydro-1,4-benzodioxin-5-ylmethanol

HRID 910102노트

반응식

HRID 910102 반응식
[OH:1][C:2]1[C:9]([OH:10])=[CH:8][CH:7]=[CH:6][C:3]=1[CH:4]=[O:5].Br[CH2:12][CH2:13]Br.C(=O)([O-])[O-].[Cs+].[Cs+].[BH4-].[Na+]>CN(C)C=O.C(O)C>[O:10]1[C:9]2[CH:8]=[CH:7][CH:6]=[C:3]([CH2:4][OH:5])[C:2]=2[O:1][CH2:13][CH2:12]1

참가 물질

7

반응물 4

HCID 78391,2-DibromoethaneHCID 10796Cesium carbonateHCID 905792,3-DihydroxybenzaldehydeHCID 4311764Sodium borohydride

생성물 1

HCID 27761822,3-dihydro-1,4-benzodioxin-5-ylmethanol수율 27%

시약·촉매·용매 2

HCID 702Ethanol용매HCID 6228Dimethylformamide용매

반응 조건

온도
20 °C

실험 절차

Dissolve 2,3-dihydroxybenzaldehyde (25 g, 181 mmol) and 1,2-dibromoethane (34 g, 181 mmol) in N,N-dimethylformamide (500 mL). Add cesium carbonate (118 g, 362 mmol), stir and reflux under nitrogen for 2 hours. Cool the reaction to 20° C., dilute with absolute ethanol (250 mL) and add sodium borohydride (6.8 g, 181 mmol). Stir at 20° C. for 1 hour and concentrate under high vacuum to remove the ethanol and dimethylformamide. Dilute the residue with diethyl ether and wash with distilled water, 0.25 molar aqueous sodium hydroxide, and aqueous saturated sodium chloride. Dry the organic phase over anhydrous magnesium sulfate, filter and concentrate under reduced pressure. Chromatograph on flash silica using a gradient from 75% hexane, 25% ethyl acetate to 25% hexane, 75% ethyl acetate to obtain 8.1 g (27%) of the desired compound as a white solid.

후처리

  1. temperaturereflux under nitrogen for 2 hours
  2. temperatureCool
  3. customthe reaction to 20° C.
  4. concentrationconcentrate under high vacuum
  5. customto remove the ethanol and dimethylformamide
  6. additionDilute the residue with diethyl ether
  7. washwash with distilled water, 0.25 molar aqueous sodium hydroxide, and aqueous saturated sodium chloride
  8. dry with materialDry the organic phase over anhydrous magnesium sulfate
  9. filtrationfilter
  10. concentrationconcentrate under reduced pressure

출처 및 근거

ORD 기록
ord-611bcce893bc4c4a9e740ec8936a08dc
출처 데이터셋
uspto-grants-2011_09
특허 번호
US08022065B2

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