Diethyl Oxalate → Ethyl 2-(3,5-dichloro-2,6-dimethoxypyridin-4-yl)-2-oxoacetate

HRID 1375408노트

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HRID 1375408 반응식
[Cl:1][C:2]1[C:3]([O:11][CH3:12])=[N:4][C:5]([O:9][CH3:10])=[C:6]([Cl:8])[CH:7]=1.[Li+].CC([N-]C(C)C)C.[C:21](OCC)(=[O:27])[C:22]([O:24][CH2:25][CH3:26])=[O:23].[Cl-].[NH4+]>C1COCC1>[Cl:8][C:6]1[C:5]([O:9][CH3:10])=[N:4][C:3]([O:11][CH3:12])=[C:2]([Cl:1])[C:7]=1[C:21](=[O:27])[C:22]([O:24][CH2:25][CH3:26])=[O:23]

참가 물질

6

반응물 4

HCID 7268Diethyl OxalateHCID 25517Ammonium ChlorideHCID 2724682Lithium diisopropylamideHCID 694735033,5-Dichloro-2,6-dimethoxypyridine

생성물 1

HCID 58786806Ethyl 2-(3,5-dichloro-2,6-dimethoxypyridin-4-yl)-2-oxoacetate수율 78%

시약·촉매·용매 1

HCID 8028Tetrahydrofuran용매2회

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온도
-78 °C

실험 절차

A solution of 5.20 g (25 mmol) of 3,5-dichloro-2,6-dimethoxypyridine (J. Bratt, H. Suschitzky, J.C.S. Perkin I, 1983:1689–1693) in 40 mL THF is added dropwise over 30 minutes to a solution of 20 mL (30 mmol) of 1.5 M LDA in 20 mL THF at −78° C. The resulting solution is stirred at −78° C. for 1 hour, and 4.5 mL (33 mmol) of diethyl oxalate is then added. The temperature is allowed to rise slowly to room temperature and aqueous ammonium chloride solution is added, and the solvent is removed under vacuum. The residue is extracted into EtOAc and chromatographed on SiO2, eluting with hexane-EtOAc (9:1), to give 5.97 g (78%) of the title compound: mp (hexane) 195–196° C.

후처리

  1. customto rise slowly to room temperature
  2. customthe solvent is removed under vacuum
  3. extractionThe residue is extracted into EtOAc
  4. customchromatographed on SiO2
  5. washeluting with hexane-EtOAc (9:1)

출처 및 근거

ORD 기록
ord-1c76a0564a4b4b7a929680bd5d8bde0a
출처 데이터셋
uspto-grants-2007_01
특허 번호
US07169778B2

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