Water → N-Ethyl-N-[3-(3-methyl-1,2,4-triazolo[4,3-b]pyridazin-6-yl)phenyl]acetamide

Beteiligte Stoffe

Reaktionsschritte

To 12.5 g of N-[3-(3-methyl-1,2,4-triazolo[4,3-b]pyridazin-6-yl]phenyl]acetamide (U.S. Pat. No. 4,112,095) in 500 ml of dimethylformamide under argon, was added 2.47 g of sodium hydride (50% in oil). The mixture was stirred for one hour, then 4.1 ml of ethyl iodide was added. This mixture was stirred for 2.5 days, then poured into 1.5 liters of water and extracted with 150 ml portions of dichloromethane. The extracts were combined, dried and evaporated in vacuo. The residue was chromatographed on a Waters Prep 500 silica gel column, eluting with dichloromethane:methanol (97:3). Fractions 8-13 were combined, evaporated in vacuo and the solid recrystallized from dichloromethane-hexane, giving 6.54 g of the desired product, mp 180°-185° C.

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