Reaktion #71487

Reaktionsgleichung

5-(3,5-dimethoxy-phenyl)-quinoline-8-carboxylic acid

H2SO4

EtOH

→

title compound

5-(3,5-Dimethoxy-phenyl)-quinoline-8-carboxylic acid ethyl ester

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturat reflux for 30 h
2. 2
   Temperaturto cool
3. 3
   Einengenconcentrated
4. 4
   workup.ADDITIONThe residue was diluted in EtOAc
5. 5
   SonstigeThe aqueous phase was separated
6. 6
   Extraktionextracted with EtOAc
7. 7
   WaschenThe combined organic layers were washed with H2O and brine
8. 8
   Trocknendried (Na2SO4)
9. 9
   Filtrationfiltered
10. 10
    Einengenconcentrated
11. 11
    SonstigeThe residue was purified by silica gel column chromatography (Hex/EtOAc, 3:2)

Vorschrift

A mixture of 5-(3,5-dimethoxy-phenyl)-quinoline-8-carboxylic acid (Step 159.2) (2 g), H2SO4 conc. (0.6 mL) and EtOH (100 mL) was stirred at reflux for 30 h, allowed to cool and concentrated. The residue was diluted in EtOAc and a saturated aqueous solution of NaHCO3. The aqueous phase was separated and extracted with EtOAc. The combined organic layers were washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was purified by silica gel column chromatography (Hex/EtOAc, 3:2) to provide 1.77 g of the title compound as a white solid. Title compound: ESI-MS: 338.2 [M+H]+; tR=3.81 min (System 1); TLC: Rf=0.29 (Hex/EtOAc, 3:2).

Quelle