Piperonal → 5-(2,2-Dibromo-vinyl)-benzo[1,3]dioxole

HRID 24024

반응식

HRID 24024 반응식
[CH:1]1[C:6]([CH:7]=O)=[CH:5][C:4]2[O:9][CH2:10][O:11][C:3]=2[CH:2]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[C:31](Br)(Br)([Br:33])[Br:32]>C(Cl)Cl>[Br:32][C:31]([Br:33])=[CH:7][C:6]1[CH:1]=[CH:2][C:3]2[O:11][CH2:10][O:9][C:4]=2[CH:5]=1

참가 물질

5

반응물 3

HCID 8438PiperonalHCID 11205Carbon tetrabromideHCID 11776Triphenylphosphine

생성물 1

HCID 109687645-(2,2-Dibromo-vinyl)-benzo[1,3]dioxole수율 74%

시약·촉매·용매 1

HCID 6344Dichloromethane용매

실험 절차

To a solution of piperonal (4.5 g, 30 mmol) and triphenylphosphine (24 g, 90 mmol) in DCM (120 mL) in an ice-water bath was added a solution of carbontetrabromide (15 g, 45 mmol) over a 10 minutes period. After the addition completed, the ice-water bath was removed, the reaction stirred at ambient temperature for 2 h, and then quenched with saturated NaHCO3. Aqueous was separated, and extracted with dichloromethane (2 times). The organic layers were combined, dried over Na2SO4, filtered, and concentrated to give a redish colored residue, that was filtered through a short path silica gel plug, eluting with DCM/hexane (10% to 20%). Concentration of the filtrate gave the title compound (6.5 g, 74% yield) as a pale yellow liquid. 1H NMR (CDCl3) δ 7.36 (s, 1H), 7.18 (d, 1H, J=1.6 Hz), 6.95 (dd, 1H, J=1.5, 8.1 Hz), 6.79 (d, 1H, J=8.1 Hz), 5.99 (s, 2H).

후처리

  1. additionAfter the addition
  2. customthe ice-water bath was removed
  3. customquenched with saturated NaHCO3
  4. customAqueous was separated
  5. extractionextracted with dichloromethane (2 times)
  6. dry with materialdried over Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customto give a redish colored residue, that
  10. filtrationwas filtered through a short path silica gel plug
  11. washeluting with DCM/hexane (10% to 20%)

출처 및 근거

ORD 기록
ord-b1d78607255e4db591db91c514e39db9
출처 데이터셋
uspto-grants-2005_02
특허 번호
US06855722B2

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