Reaktion #78138

Reaktionsgleichung

4-(4-pyridylmethyl)-1(2H)-phthalazinone

phosphorus pentoxide

triethylamine hydrochloride

4-chloroaniline

ammonia

→

title compound

1-(4-Chloroanilino)-4-(4-pyridylmethyl)phthalazine

Lösungsmittel

water

chloroform

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturis heated
2. 2
   Sonstigehas formed (about 20 min)
3. 3
   workup.STIRRINGthe reaction mixture is stirred for 3 h at 200° C
4. 4
   TemperaturAfter the reaction mixture has cooled to about 100° C.
5. 5
   workup.STIRRINGStirring
6. 6
   Sonstigereaches about 30° C.
7. 7
   SonstigeAs soon as a diphasic mixture has formed
8. 8
   Sonstigethe organic phase is separated off
9. 9
   Trocknendried over anhydrous sodium sulfate
10. 10
    Filtrationfiltered
11. 11
    Sonstigethe filtrate evaporated on a RE to a volume of about 50 ml
12. 12
    workup.ADDITIONto which 100 ml acetate is then added
13. 13
    Temperaturthe mixture is cooled in an ice bath
14. 14
    SonstigeThe crystallizate obtained
15. 15
    Filtrationis filtered off
16. 16
    Waschenwashed with acetate and ether
17. 17
    SonstigeAfter recrystallization from methanol
18. 18
    Sonstigedrying under HV for 8 h at 120° C.

Vorschrift

A mixture of 14.19 g (0.1 mol) phosphorus pentoxide, 13.77 g (0.1 mol) triethylamine hydrochloride and 12.76 g (0.1 mol) 4-chloroaniline is heated and stirred in a nitrogen atmosphere at 200° C. until a homogeneous melt has formed (about 20 min). To the melt, 5.93 g (0.025 mol) 4-(4-pyridylmethyl)-1(2H)-phthalazinone (for preparation see German Auslegeschrift no. 1061 788 [published Jul. 23, 1959]) is added, and the reaction mixture is stirred for 3 h at 200° C. After the reaction mixture has cooled to about 100° C., 200 ml of water is added. Stirring is continued until the temperature reaches about 30° C., and then 20 ml conc. ammonia (30% aqueous ammonium hydroxide solution) and 900 ml chloroform are added consecutively. As soon as a diphasic mixture has formed, the organic phase is separated off, dried over anhydrous sodium sulfate, filtered, and the filtrate evaporated on a RE to a volume of about 50 ml, to which 100 ml acetate is then added, and the mixture is cooled in an ice bath. The crystallizate obtained is filtered off and washed with acetate and ether. After recrystallization from methanol and drying under HV for 8 h at 120° C., the title compound is obtained; m.p. 194-195° C.; ESI-MS: (M+H)+=347.

Quelle