Bromine → 2,3-Dibromo-4-methylpyridine

HRID 1782581

반응식

HRID 1782581 반응식
[Br:1]Br.[Br:3][C:4]1[C:5](N)=[N:6][CH:7]=[CH:8][C:9]=1[CH3:10].N([O-])=O.[Na+]>Br.O>[Br:1][C:5]1[C:4]([Br:3])=[C:9]([CH3:10])[CH:8]=[CH:7][N:6]=1

참가 물질

6

반응물 3

HCID 24408BromineHCID 144180433-Bromo-4-methylpyridin-2-amineHCID 23668193Sodium Nitrite

생성물 1

HCID 223086952,3-Dibromo-4-methylpyridine수율 47%

시약·촉매·용매 2

HCID 260Hydrogen Bromide용매HCID 962Water용매

반응 조건

온도
10 °C

실험 절차

Bromine (0.35 mL, 6.8 mmol) was added dropwise to a solution of 3-bromo-4-methyl-pyridin-2-ylamine (0.44 g, 2.4 mmol) in 48% HBr (3 mL) at −10° C. to give an orange slurry. After 5 minutes NaNO2 (0.47 g, 6.8 mmol), dissolved in water (1.5 mL), was added dropwise over 5 minutes. The dark brown mixture was slowly warmed to 10° C. over 3.5 h and then cooled to 0° C. and quenched with 10N NaOH until pH˜12. The resulting orange slurry was extracted with CH2Cl2 (3×50 mL), dried (Na2SO4), filtered and concentrated in vacuo to give an orange/brown solid. Purification by column chromatography on silica gel (Hexanes:Et2O, 7:3, v/v) yielded 2,3-dibromo-4-methyl-pyridine (0.28 g, 47%) as a pale yellow solid. 1H NMR (CDCl3) δ 2.48 (s, 3H), 7.11 (d, 1H, J=6.0 Hz), 8.16 (d, 1H, J=6.0 Hz).

후처리

  1. customto give an orange slurry
  2. additionwas added dropwise over 5 minutes
  3. temperaturecooled to 0° C.
  4. customquenched with 10N NaOH until pH˜12
  5. extractionThe resulting orange slurry was extracted with CH2Cl2 (3×50 mL)
  6. dry with materialdried (Na2SO4)
  7. filtrationfiltered
  8. concentrationconcentrated in vacuo
  9. customto give an orange/brown solid
  10. customPurification by column chromatography on silica gel (Hexanes

출처 및 근거

ORD 기록
ord-f5e070cde61946ea91f96e687bae81a4
출처 데이터셋
uspto-grants-2009_03
특허 번호
US07498346B2

연결된 노트

불러오는 중…