Dimethylformamide → 1h-Pyrazolo[4,3-b]pyridine-5,6-dicarboxylic acid,1-methyl-,5,6-dimethyl ester

HRID 1733831노트

반응식

HRID 1733831 반응식
CN(C)[CH:3]=[O:4].P(Cl)(Cl)(Cl)=[O:7].[CH3:11][N:12]1[CH:16]=[C:15]([NH:17][C:18]([CH2:28]C)=[C:19]([C:24](OC)=O)[C:20]([O:22][CH3:23])=[O:21])[CH:14]=[N:13]1.C[N+](C)=CCl.[Cl-]>ClC(Cl)C>[CH3:11][N:12]1[C:16]2[C:15](=[N:17][C:18]([C:28]([O:4][CH3:3])=[O:7])=[C:19]([C:20]([O:22][CH3:23])=[O:21])[CH:24]=2)[CH:14]=[N:13]1

참가 물질

6

반응물 4

HCID 6228DimethylformamideHCID 24813Phosphorus oxychlorideHCID 77311Chloro-N,N-dimethylformiminium chlorideHCID 19417344Dimethyl [(1-methylpyrazol-4-yl)amino]butenedicarboxylate

생성물 1

HCID 199582161h-Pyrazolo[4,3-b]pyridine-5,6-dicarboxylic acid,1-methyl-,5,6-dimethyl ester수율 71.4%

시약·촉매·용매 1

HCID 63651,1-Dichloroethane용매2회

반응 조건

온도
-5 °C

실험 절차

Dimethylformamide (7.4 mL, 0.096 mol) is dissolved in 125 mL dichloroethane and the mixture cooled to -5° C. in an acetone/ice bath. Phosphorous oxychloride (8.9 mL, 0.095 mol) is added in one portion and the clear colorless solution is allowed to warm slowly to room temperature, gradually turning yellow. The unpurified dimethyl [(1-methylpyrazol-4-yl)amino]-butenedicarboxylate is dissolved in 75 mL of dichloroethane and added to the chilled Vilsmeier reagent dropwise keeping the reaction temperature below 5° C. The mixture is allowed to warm slowly to room temperature over four hours, and then is heated to reflux for one hour. The mixture is concentrated to a solid which is chromatographed using 3:1 hexanes/ethyl acetate. The fractions containing the desired product are combined and concentrated to give the product as a white solid (16.93 g, 71.4%), melting point 148°-149° C.

후처리

  1. temperatureto warm slowly to room temperature
  2. customthe reaction temperature below 5° C
  3. temperatureto warm slowly to room temperature over four hours
  4. temperatureis heated
  5. temperatureto reflux for one hour
  6. concentrationThe mixture is concentrated to a solid which
  7. customis chromatographed
  8. additionThe fractions containing the desired product
  9. concentrationconcentrated

출처 및 근거

ORD 기록
ord-d2c683369da8493e81652986b6d426f7
출처 데이터셋
uspto-grants-1996_07
특허 번호
US05532207

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