Reaktion #430542

Reaktionsgleichung

5-dimethylamino-1-naphthalenesulphonyl chloride

Sodium hydride

2-amino-3,5-dibromopyrazine

hydrogen

→

5-(dimethylamino)-N-(3,5-dibromo-2-pyrazinyl)-1-naphthalenesulphonamide

Ausbeute 5.3%

Lösungsmittel

N,N-dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeVolatile material was removed by evaporation and water (50 ml)
2. 2
   workup.ADDITIONwas added to the residue
3. 3
   ExtraktionThe mixture was extracted with ethyl acetate (20 ml)
4. 4
   Extraktionextracted with ethyl acetate (3×25 ml)
5. 5
   WaschenThe extracts were washed with water (20 ml) and saturated sodium chloride solution (20 ml)
6. 6
   Trocknendried (MgSO4)
7. 7
   SonstigeVolatile material was removed by evaporation
8. 8
   Sonstigethe residue was purified by elution with dichloromethane through a silica gel Mega Bond Elut column
9. 9
   SonstigeThe resulting foam was triturated with ether/hexane (1:1 v/v)

Vorschrift

Sodium hydride (60% dispersion in oil; 0.16 g) was added to a solution of 2-amino-3,5-dibromopyrazine (0.506 g) in N,N-dimethylformamide (30 ml). When evolution of hydrogen ceased, 5-dimethylamino-1-naphthalenesulphonyl chloride (0.54 g) was added and the solution was heated at 95° C. for 18 hours. Volatile material was removed by evaporation and water (50 ml) was added to the residue. The mixture was extracted with ethyl acetate (20 ml), and the aqueous layer was neutralised with 0.05H aqueous acetic acid (40 ml) and extracted with ethyl acetate (3×25 ml). The extracts were washed with water (20 ml) and saturated sodium chloride solution (20 ml) and dried (MgSO4). Volatile material was removed by evaporation and the residue was purified by elution with dichloromethane through a silica gel Mega Bond Elut column. The resulting foam was triturated with ether/hexane (1:1 v/v) to give 5-(dimethylamino)-N-(3,5-dibromo-2-pyrazinyl)-1-naphthalenesulphonamide (0.052 g), m.p. 178° C.; mass spectrum (+ve FAB, methanol/NBA): 485 (M+H)+.

Quelle