Reaktion #63899

Reaktionsgleichung

dimethylamine hydrochloride

sodium bicarbonate

3-methyl-6-[3-(amino)phenyl]-1,2,4-triazolo[4,3-b]pyridazine

diisopropylethylamine

trichloromethyl chloroformate

Diisopropylethylamine

→

desired product

N,N-Dimethyl-N'-[3-(3-methyl-1,2,4-triazolo[4,3-b]pyridazin-6-yl)phenyl]urea

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture was stirred for 1 hour
2. 2
   Extraktionextracted with dichloromethane
3. 3
   Sonstigedried
4. 4
   Sonstigethe solvent removed
5. 5
   SonstigeThe residue was chromatographed on a 200 g silica gel column
6. 6
   Sonstigeevaporated
7. 7
   Sonstigethe solid recrystallized from dichloromethane-methanol-hexane

Vorschrift

To a soluton of 1.9 g of 3-methyl-6-[3-(amino)phenyl]-1,2,4-triazolo[4,3-b]pyridazine and 1.6 of diisopropylethylamine in dichloromethane was added 1.67 g of trichloromethyl chloroformate. This mixture was stirred for 1 hour, then two equivalents of dimethylamine hydrochloride were added. Diisopropylethylamine was added until solution was complete then the mixture was stirred for 1 hour, poured into saturated aqueous sodium bicarbonate and extracted with dichloromethane. The extracts were combined, dried and the solvent removed. The residue was chromatographed on a 200 g silica gel column using dichloromethane:methanol (95:5) as eluent. The active fractions were combined, evaporated and the solid recrystallized from dichloromethane-methanol-hexane, giving 1.33 g of the desired product as pale yellow crystals, mp 237°-239° C.

Quelle