Phosphorus oxychloride → 3,5-Dichloro-2-ethylquinoxaline

HRID 1019808노트

반응식

HRID 1019808 반응식
[Cl:1][C:2]1[CH:3]=[CH:4][CH:5]=[C:6]2[C:11]=1[NH:10][C:9](=O)[C:8]([CH2:13][CH3:14])=[N:7]2.O=P(Cl)(Cl)[Cl:17]>>[Cl:17][C:9]1[C:8]([CH2:13][CH3:14])=[N:7][C:6]2[C:11]([N:10]=1)=[C:2]([Cl:1])[CH:3]=[CH:4][CH:5]=2

참가 물질

3

반응물 2

HCID 24813Phosphorus oxychlorideHCID 866985098-chloro-3-ethylquinoxalin-2(1H)-one

생성물 1

HCID 866985103,5-Dichloro-2-ethylquinoxaline수율 77.2%

실험 절차

A thick slurry of 8-chloro-3-ethylquinoxalin-2(1H)-one (1.00 Kg, 4.79 mol) in POCl3 (2.68 L, 28.8 mol) was stirred at 100° C. for 2 h. At this time LC-MS analysis showed that the reaction was complete. After the removal of most of the POCl3 under reduced pressure, the residue was poured carefully into ice-water and neutralized with a combination of 2M aq. NaOH and saturated aq. NaHCO3. The resulting suspension was extracted with DCM (3×4 L). The organic phase was washed with brine, dried over anhydrous Na2SO4, filtered, and evaporated under reduced pressure. The crude was purified by flash column chromatography eluting with hexane/EtOAc (30/1) to give 3,5-dichloro-2-ethylquinoxaline (840 g) as a white solid. 1H NMR (DMSO-d6) δ ppm 8.01-8.08 (m, 2H), 7.84 (t, J=8.0 Hz, 1H), 3.10-3.17 (d, J=7.3 Hz, 2H), 1.36 (t, J=7.3 Hz, 3H). Mass Spectrum (ESI) m/z=227.1 (M+1).

후처리

  1. customAfter the removal of most of the POCl3 under reduced pressure
  2. additionthe residue was poured carefully into ice-water
  3. extractionThe resulting suspension was extracted with DCM (3×4 L)
  4. washThe organic phase was washed with brine
  5. dry with materialdried over anhydrous Na2SO4
  6. filtrationfiltered
  7. customevaporated under reduced pressure
  8. customThe crude was purified by flash column chromatography
  9. washeluting with hexane/EtOAc (30/1)

출처 및 근거

ORD 기록
ord-b7f33681555c42429457f08d8b69438d
출처 데이터셋
uspto-grants-2014_05
특허 번호
US08716290B2

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