Reaktion #95501

Reaktionsgleichung

1-(2-nitrophenyl)spiro[indoline-3,4'-piperidine]hydrochloride

→

1-(2-aminophenyl)spiro[indoline-3,4'-piperidine]dihydrochloride

Lösungsmittel

hydrochloric acid

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter heating
2. 2
   Temperaturat reflux for 3 hours
3. 3
   Filtrationthe reaction mixture (at room temperature) is filtered
4. 4
   Extraktionextracted with chloroform
5. 5
   FiltrationThe organic phase is filtered through a pad of celite on a sintered glass funnel
6. 6
   Waschenthe filtrate is washed with brine
7. 7
   Trocknendried over anhydrous sodium sulfate
8. 8
   Einengenconcentrated
9. 9
   Sonstigeto give 4.50 g of the crude free base of the product
10. 10
    SonstigeConversion to the hydrochloric acid salt with dichloromethane-ether/ethereal hydrochloric acid and two recrystallizations from hot isopropanol-methanol

Vorschrift

3.76 g of iron powder is added portionwise to a rapidly stirred ice cold slurry of 7.66 g of 1-(2-nitrophenyl)spiro[indoline-3,4'-piperidine]hydrochloride of Example 38 in 11.8 ml of concentrated hydrochloric acid and 300 ml of methanol. After heating at reflux for 3 hours, the reaction mixture (at room temperature) is filtered, made basic using 10% aqueous sodium hydroxide and extracted with chloroform. The organic phase is filtered through a pad of celite on a sintered glass funnel and the filtrate is washed with brine, dried over anhydrous sodium sulfate and concentrated to give 4.50 g of the crude free base of the product. Conversion to the hydrochloric acid salt with dichloromethane-ether/ethereal hydrochloric acid and two recrystallizations from hot isopropanol-methanol affords 1-(2-aminophenyl)spiro[indoline-3,4'-piperidine]dihydrochloride, mp 282.5° C., dec.

Quelle