Reaktion #725324

ord-a087e1af75bf4fe3b9370c468e44f109

Reaktionsgleichung

CC(=O)c1cc2c(c(Cl)c1O)OC(/C(O)=N\O)C2
acid 4a
CC(=O)c1cc2c(c(Cl)c1O)OC(/C(O)=N\O)C2
(E)-5-ACETYL-7-CHLORO-2,3-DIHYDRO-6-HYDROXYBENZOFURAN-2-CARBOXYLIC ACID OXIME
C1CCOC1
tetrahydrofuran
O=S(=O)(O)O
sulfuric acid
→
CCO/C(=N/O)C1Cc2cc(C(C)=O)c(O)c(Cl)c2O1
white crystals
Ausbeute 76.1%
CCO/C(=N/O)C1Cc2cc(C(C)=O)c(O)c(Cl)c2O1
ETHYL (E)-5-ACETYL-7-CHLORO-2,3-DIHYDRO-6-HYDROXYBENZOFURAN-2-CARBOXYLATE OXIME
Ausbeute 76.1%

Edukte

CC(=O)c1cc2c(c(Cl)c1O)OC(/C(O)=N\O)C2
acid 4a
CC(=O)c1cc2c(c(Cl)c1O)OC(/C(O)=N\O)C2
(E)-5-ACETYL-7-CHLORO-2,3-DIHYDRO-6-HYDROXYBENZOFURAN-2-CARBOXYLIC ACID OXIME
C1CCOC1
tetrahydrofuran
O=S(=O)(O)O
sulfuric acid

Reagenzien

Keine

Lösungsmittel

CCO
ethanol

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    SonstigeThe resulting solution was evaporated
  2. 2
    workup.DISSOLUTIONthe residue dissolved in ethyl acetate
  3. 3
    Waschenwashed with aqueous sodium bicarbonate and brine
  4. 4
    Trocknendried over magnesium sulfate
  5. 5
    Sonstigeevaporated
  6. 6
    SonstigeRecrystallization from ethyl acetate/hexane

Vorschrift

The acid 4a was esterified by stirring in a solution of tetrahydrofuran, ethanol, and concentrated sulfuric acid (39:60:1) for 16 hours at room temperature. The resulting solution was evaporated and the residue dissolved in ethyl acetate, washed with aqueous sodium bicarbonate and brine, dried over magnesium sulfate, and evaporated. Recrystallization from ethyl acetate/hexane furnished 76.1% of white crystals, m.p. 154°-155° C. Anal. (C13H14ClNO5) C,H,N.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US04560558uspto-grants-1985_12