1,2-Dibromoethane → 6-Methyl-2,3-dihydro-1,4-benzodioxine

HRID 1640026노트

반응식

HRID 1640026 반응식
[CH3:1][C:2]1[CH:3]=[C:4]([OH:9])[C:5]([OH:8])=[CH:6][CH:7]=1.C(=O)([O-])[O-].[K+].[K+].Br[CH2:17][CH2:18]Br>CC(C)=O>[CH3:1][C:2]1[CH:7]=[CH:6][C:5]2[O:8][CH2:17][CH2:18][O:9][C:4]=2[CH:3]=1

참가 물질

5

반응물 3

HCID 78391,2-DibromoethaneHCID 99584-MethylcatecholHCID 11430Potassium Carbonate

생성물 1

HCID 124003766-Methyl-2,3-dihydro-1,4-benzodioxine수율 54%

시약·촉매·용매 1

HCID 180Acetone용매

실험 절차

A mixture of 4-methylbenzene-1,2-diol (10.0 g, 80.5 mmol) and potassium carbonate (111.3 g, 805.0 mmol) in acetone (300 mL) was stirred at room temperature for 1 h. After this time, 1,2-dibromoethane (27.7 mL, 322.0 mmol) was added and the reaction stirred at reflux for 5 d. After this time, the solvents were removed under reduced pressure and the solids redissolved in water (500 mL). The aqueous layer was then extracted three times with ethyl acetate (200 mL). The combined organic extracts were then dried over magnesium sulfate, filtered, and concentrated under reduced pressure. Purification by flash chromatography (silica, 1:20 ethyl acetate/hexanes) afforded 6-methyl-2,3-dihydrobenzo[b][1,4]dioxine (6.4 g, 54%) as a green oil: 1H NMR (500 MHz, CDCl3) δ 6.74 (d, J=8.5 Hz, 1H), 6.67 (d, J=2.0 Hz, 1H), 6.63 (dd, J 2.0, 8.0 Hz, 1H), 4.22 (m, 4H), 2.24 (s, 3H).

후처리

  1. stirringthe reaction stirred
  2. temperatureat reflux for 5 d
  3. customAfter this time, the solvents were removed under reduced pressure
  4. dissolutionthe solids redissolved in water (500 mL)
  5. extractionThe aqueous layer was then extracted three times with ethyl acetate (200 mL)
  6. dry with materialThe combined organic extracts were then dried over magnesium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated under reduced pressure
  9. customPurification by flash chromatography (silica, 1:20 ethyl acetate/hexanes)

출처 및 근거

ORD 기록
ord-731b193a238a42fc9d92b2b02dc1ea55
출처 데이터셋
uspto-grants-2012_02
특허 번호
US08110681B2

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