Water → 8-[1-(4-Chlorophenoxy)ethyl]-1,2,4-triazolo[4,3-b]pyridazine

Participants

Reaction Steps

A solution of 4-(4-chlorophenoxy)-1-(dimethylamino)-1-penten-3-one (14.5 g) in glacial acetic acid (100 ml) was added dropwise to a solution of 4-amino-1,2,4-triazole (5.0 g) in glacial acetic acid (100 ml). The solution was boiled under reflux for 4 hours and then poured into water (400 ml). The mixture was extracted with toluene. The combined organic extracts were washed with 10% sodium bicarbonate solution, then with water, dried over anhydrous magnesium sulphate, filtered, and evaporated under reduced pressure. Flash column chromatography of the residue on silica gel, using ethyl acetate/petroleum ether 1:1 as the mobile phase, afforded 1.52 g of 8-[1-(4-chlorophenoxy)ethyl]-1,2,4-triazolo[4,3-b]pyridazine. A pure sample was obtained by recrystallisation from a mixture of ethyl acetate and hexane, m.p. 98-99° C.

Provenance & Evidence