Diethyl Oxalate → 5-Methoxy-2-thiopheneglyoxylic acid ethyl ester

HRID 838886노트

반응식

HRID 838886 반응식
[CH3:1][O:2][C:3]1[S:4][CH:5]=[CH:6][CH:7]=1.C([Li])CCC.S1C=CC=C1[Li].[C:19](OCC)(=[O:25])[C:20]([O:22][CH2:23][CH3:24])=[O:21].[NH4+].[Cl-]>C1COCC1.CCCCCC>[CH2:23]([O:22][C:20](=[O:21])[C:19]([C:5]1[S:4][C:3]([O:2][CH3:1])=[CH:7][CH:6]=1)=[O:25])[CH3:24]

참가 물질

8

반응물 5

HCID 7268Diethyl OxalateHCID 25517Ammonium ChlorideHCID 856102-MethoxythiopheneHCID 178418339ButyllithiumHCID 178418439HCID 178418439, 화합물

생성물 1

HCID 544362655-Methoxy-2-thiopheneglyoxylic acid ethyl ester

시약·촉매·용매 2

HCID 8028Tetrahydrofuran용매2회HCID 8058Hexane용매

실험 절차

2-Methoxythiophene (15.4 g) is dissolved in 100 ml anhydrous THF and butyl lithium (0.135 moles) in hexane is added dropwise. The solution is stirred at room temperature 15 hr and then heated at reflux for 1 hr. After cooling, the clear solution is tranferred to a dropping funnel by means of a siphon. The solution of thienyl lithium is added dropwise to a solution of diethyl oxalate (19.7 g) in 150 ml THF at -78° C. After stirring 2 hr at -78° C, the mixture is brought to -10° C and treated with saturated NH4Cl solution. The aqueous fraction is separated and extracted several times with ether. The combined ether extracts are washed with water and brine, dried (MgSO4) and concentrated. Chromatography on silica gel (eluant = benzene) gives 5-methoxy-2-thiopheneglyoxylic acid ethyl ester (2; X1 = CH3O, X2 and X3 = H and R10 = C2H5); mp 136° - 137° C after recrystallization from benzene-hexane.

후처리

  1. temperatureheated
  2. temperatureat reflux for 1 hr
  3. temperatureAfter cooling
  4. customthe clear solution is tranferred to a dropping funnel by means of a siphon
  5. stirringAfter stirring 2 hr at -78° C
  6. customis brought to -10° C
  7. customThe aqueous fraction is separated
  8. extractionextracted several times with ether
  9. washThe combined ether extracts are washed with water and brine
  10. dry with materialdried (MgSO4)
  11. concentrationconcentrated

출처 및 근거

ORD 기록
ord-8c2c60c1862d4e51b99634e446e1b166
출처 데이터셋
uspto-grants-1978_06
특허 번호
US04093628

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