Water → 7-fluoro-2H-chromene

HRID 440683노트

반응식

HRID 440683 반응식
[F:1][C:2]1[CH:12]=[CH:11][C:5]2[CH:6](O)[CH2:7][CH2:8][O:9][C:4]=2[CH:3]=1.C1(C)C=CC(S(O)(=O)=O)=CC=1.O>C1(C)C=CC=CC=1>[F:1][C:2]1[CH:12]=[CH:11][C:5]2[CH:6]=[CH:7][CH2:8][O:9][C:4]=2[CH:3]=1

참가 물질

5

반응물 3

HCID 962WaterHCID 6101p-Toluenesulfonic acidHCID 224047977-Fluorochroman-4-ol

생성물 1

HCID 224047387-fluoro-2H-chromene수율 13.3%

시약·촉매·용매 1

HCID 1140Toluene용매

실험 절차

A reaction vessel charged with 0.5 gram (0.03 mole) of 3,4-dihydro-7-fluoro-4-hydroxy-2H-1-benzopyran and 0.02 gram (catalyst) of p-toluenesulfonic acid in 50 mL of toluene was fitted with a Soxhlet extractor containing molecular sieves (3-4 angstrom). The stirred contents of the reaction vessel was heated at reflux for 90 minutes, during which time the water by-product was collected on the molecular sieves. The reaction mixture was combined with the reaction mixture of another preparation of this compound and concentrated under reduced pressure to a residue. The residue was subjected to column chromatography on silica gel, with 1:9 ethyl acetate:hexane as the eluant. The product-containing fractions were combined and concentrated under reduced pressure, yielding 0.6 gram of 7-fluoro-2H-1-benzopyran. The NMR spectrum was consistent with the proposed structure. This reaction was repeated several times.

후처리

  1. customwas fitted with a Soxhlet extractor
  2. additioncontaining molecular sieves (3-4 angstrom)
  3. temperatureThe stirred contents of the reaction vessel was heated
  4. customwas collected on the molecular sieves
  5. additionThe reaction mixture was combined with the reaction mixture of another preparation of this compound
  6. concentrationconcentrated under reduced pressure to a residue
  7. concentrationconcentrated under reduced pressure

출처 및 근거

ORD 기록
ord-6d1fadf018ad45ec9fb672dc746cf772
출처 데이터셋
uspto-grants-1996_05
특허 번호
US05521147

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