Reaktion #430550

Reaktionsgleichung

5-Dimethylamino-1-naphthalenesulphonyl chloride

2-amino-5-bromo-3-methoxypyrazine

→

5-dimethylamino-N-(5-bromo-3-methoxy-2-pyrazinyl)-1-naphthalenesulphonamide

Ausbeute 23.1%

Lösungsmittel

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeVolatile material was removed by evaporation and dichloromethane (250 ml)
2. 2
   workup.ADDITIONwas added to the residue
3. 3
   SonstigeInsoluble material was removed by filtration
4. 4
   Waschenthe filtrate was washed with water (100 ml) and saturated sodium chloride solution (100 ml)
5. 5
   workup.ADDITIONThe solution was treated with charcoal
6. 6
   Trocknendried (MgSO4)
7. 7
   SonstigeThe solvent was removed by evaporation
8. 8
   Sonstigethe residue was purified by flash chromatography
9. 9
   Wascheneluting with ethyl acetate/hexane (1:4 v/v)
10. 10
    SonstigeThe resulting solid was triturated with ether
11. 11
    Sonstigerecrystallised from ethanol

Vorschrift

5-Dimethylamino-1-naphthalenesulphonyl chloride (15.2 g) and 2-amino-5-bromo-3-methoxypyrazine (obtained as described in Gazz. Chim. Ital. 1960, 90, 1807) (9.5 g) were mixed intimately in a mortar and pestle and added to pyridine (150 ml) at 0° C. The solution was kept at 0° C. for 1 hour and then heated at 80° C. for 18 hours. Volatile material was removed by evaporation and dichloromethane (250 ml) was added to the residue. Insoluble material was removed by filtration and the filtrate was washed with water (100 ml) and saturated sodium chloride solution (100 ml). The solution was treated with charcoal and dried (MgSO4). The solvent was removed by evaporation and the residue was purified by flash chromatography, eluting with ethyl acetate/hexane (1:4 v/v). The resulting solid was triturated with ether and recrystallised from ethanol to give 5-dimethylamino-N-(5-bromo-3-methoxy-2-pyrazinyl)-1-naphthalenesulphonamide (4.7 g), m.p. 166°-167° C.; 1H NMR (d6 -DMSO): 2.8 (s,6H), 3.9 (s,3H), 7.2 (d,1H), 7.55-7.7 (d,2H), 7.8 (s,1H), 8.3 (d,1H), 8.4-8.5 (m,2H), 11.5 (s,1H); mass spectrum (+ve CI): 437 (M+H)+.

Quelle