Reaktion #445454

Reaktionsgleichung

4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)-oxy]butanoic acid

ethanol

sulfuric acid

sulfuric acid

→

ethyl 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture is refluxed for 1 hr
2. 2
   workup.ADDITION, treated with 3 Å molecular sieves
3. 3
   Temperaturrefluxed for 1 hr
4. 4
   Filtrationfiltered
5. 5
   workup.ADDITIONtreated with solid potassium carbonate
6. 6
   workup.DISTILLATIONThe ethanol is distilled at reduced pressure

Vorschrift

To a suspension of 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)-oxy]butanoic acid (0.5 g, 0.0012 mole) in absolute ethanol (50 ml) is added conc. sulfuric acid and the mixture is refluxed for 1 hr., treated with 3 Å molecular sieves and stirred at 25° for 18 hours. The reaction mixture is treated with more conc. sulfuric acid (0.2 ml) refluxed for 1 hr, filtered and treated with solid potassium carbonate. The ethanol is distilled at reduced pressure to give ethyl 4-[(6,7-dichloro-2-cyclopentyl-2,3-dihydro-2-methyl-1-oxo-1H-inden-5-yl)oxy]butanoate which is purified by chromatography on silica gel eluted with methylene chloride-tetrahydrofuran (100:1).

Quelle