反应详情

A solution of 84.3 g of 6-chloro-8-methyl-1,2,4-triazolo [4,3-b]pyridazine, 62.4 g of 1,2,5,6-tetrahydropyridine and 101 g of triethylamine in one liter of ethanol was refluxed under nitrogen for 21 hours. The bulk of the solvent was removed at the rotary evaporator. The residual semi-solid was dissolved in 1000 ml of dichloromethane and washed with 500 ml of saturated sodium bicarbonate solution. The aqueous layer was back washed with fresh dichloromethane (2×200 ml) and the combined organic layers were dried over anhydrous sodium sulfate. Evaporation of the solvent gave a light-brown oil which slowly solidified. This was taken up in 230 ml of hot ethyl acetate and cooled. After cooling the mixture slowly to room temperature and then to 5° C., the cream colored needles which formed were collected, washed with ethyl ether/ethyl acetate (2/1) then with ethyl ether and dried to give 8-methyl-6-(1,2,5,6-tetrahydropyridin-1-yl)-1,2,4-triazolo-[4,3-b]pyridazine melting at about 103°-106° C.

1. customThe bulk of the solvent was removed at the rotary evaporator
2. dissolutionThe residual semi-solid was dissolved in 1000 ml of dichloromethane
3. washwashed with 500 ml of saturated sodium bicarbonate solution
4. washThe aqueous layer was back washed with fresh dichloromethane (2×200 ml)
5. dry with materialthe combined organic layers were dried over anhydrous sodium sulfate
6. customEvaporation of the solvent
7. customgave a light-brown oil which
8. temperaturecooled
9. customto 5° C., the cream colored needles which formed
10. customwere collected
11. washwashed with ethyl ether/ethyl acetate (2/1)
12. dry with materialwith ethyl ether and dried