Reaktion #355023

Reaktionsgleichung

ammonium hydroxide

2,2'-bis(phenylethynyl)-5,5'-dinitrobenzidine

ammonium hydroxide

→

2,2'-bis(phenylethynyl)-5,5'-diaminobenzidine

Ausbeute 76.0%

Lösungsmittel

dioxane

dioxane

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe resultant dark suspension was stirred
2. 2
   workup.ADDITIONwas added
3. 3
   TemperaturRefluxing
4. 4
   workup.WAITwas continued for 30 minutes
5. 5
   Temperaturthe reaction mixture was cooled
6. 6
   Extraktionextracted three times with 100 ml
7. 7
   EinengenThe combined chloroform extracts were concentrated to dryness on a rotary evaporator
8. 8
   workup.DISSOLUTIONThe residue was dissolved in methylene chloride (20 ml.)
9. 9
   Filtrationfiltered after which the filtrate
10. 10
    workup.ADDITIONwas poured
11. 11
    workup.STIRRINGwith stirring into 20 ml
12. 12
    FiltrationThe resultant precipitate was filtered
13. 13
    Waschenwashed with hexane
14. 14
    Sonstigedried at 23° C in a vacuum oven at 1 mm of Hg for 24 hours

Vorschrift

A solution of 2,2'-bis(phenylethynyl)-5,5'-dinitrobenzidine (0.474 g, 0.00100 mol) in dioxane (50 ml), freshly distilled from FeSO4 (3.65 g, 0.024 mol), was added to a boiling solution of FeSO4 (3.65 g, 0.024 mol) in water (50 ml.) which was stirred under nitrogen. After 5 minutes, ammonium hydroxide (20 ml, 30%) was added slowly followed by 20 ml. more of dioxane. The resultant dark suspension was stirred and refluxed for 30 minutes at which point additional ammonium hydroxide (20 ml) was added. Refluxing was continued for 30 minutes and then the reaction mixture was cooled and extracted three times with 100 ml. of chloroform. The combined chloroform extracts were concentrated to dryness on a rotary evaporator. The residue was dissolved in methylene chloride (20 ml.) and filtered after which the filtrate was poured with stirring into 20 ml. of hexane. The resultant precipitate was filtered, washed with hexane, and dried at 23° C in a vacuum oven at 1 mm of Hg for 24 hours to give 0.313 g (76% yield) of 2,2'-bis(phenylethynyl)-5,5'-diaminobenzidine which softened above 100° C to a viscous melt.

Quelle