反应详情

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.

1. temperatureAfter heating
2. temperatureat reflux for 3 hours
3. filtrationthe reaction mixture (at room temperature) is filtered
4. extractionextracted with chloroform
5. filtrationThe organic phase is filtered through a pad of celite on a sintered glass funnel
6. washthe filtrate is washed with brine
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationconcentrated
9. customto give 4.50 g of the crude free base of the product
10. customConversion to the hydrochloric acid salt with dichloromethane-ether/ethereal hydrochloric acid and two recrystallizations from hot isopropanol-methanol