Reaktion #80441

Reaktionsgleichung

4-Cyanophenyl hydrazine hydrochloride

4-benzoyloxycyclohexanone

→

3-benzoyloxy-6-cyano-1,2,3,4-tetrahydrocarbazole

Ausbeute 47.9%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture was heated
2. 2
   Temperaturunder reflux for 1.5 hr
3. 3
   Temperaturto cool
4. 4
   Filtrationthe mixture was filtered
5. 5
   Sonstigethe filtrate was evaporated to dryness
6. 6
   Sonstigeto give a solid precipitate, which
7. 7
   Sonstigewas purified by chromatography (SiO2 ; hexane/ethyl acetate)

Vorschrift

4-Cyanophenyl hydrazine hydrochloride (20.2 g) and 4-benzoyloxycyclohexanone (25.9 g) were dissolved in glacial acetic acid (400 ml) and the mixture was heated under reflux for 1.5 hr. After allowing to cool, the mixture was filtered, and the filtrate was evaporated to dryness, and neutralized with aqueous sodium bicarbonate solution to give a solid precipitate, which was purified by chromatography (SiO2 ; hexane/ethyl acetate) to give 3-benzoyloxy-6-cyano-1,2,3,4-tetrahydrocarbazole (18 g). This product (11.6 g) was suspended in ethanol (230 ml) and treated with 2.5% aqueous potassium hydroxide solution (120 ml), and heated under reflux for 1 hr. The cooled mixture was neutralized with glacial acetic acid and evaporated to a solid residue, which was washed with water, and dried to give 3-hydroxy-6-cyano-1,2,3,4-tetrahydrocarbazole (6.6 g).

Quelle