反应详情

温度

-75 °C

220 ml of lithium hexamethyldisilazide (1.0 M tetrahydrofuran solution) was added to a 4-L tetrahydrofuran solution of 68.3 g of 5-methyl-1-trityl-1,5-dihydroimidazo[4,5-d]pyridazin-4-one at −75° C. under a nitrogen atmosphere, and the mixture was stirred at −75° C. for 1 hour. Then, 200 ml of a tetrahydrofuran solution of 82.3 g of hexachloroethane was added to the solution. The mixture was allowed to warm to −20° C. 5 L of 5% aqueous ammonium chloride was added, and the mixture was extracted with 4 L of ethyl acetate. The organic layer was washed successively with 5 L of water and 5 L of a saturated sodium chloride solution. The solution was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was suspended in 150 ml of t-butyl methyl ether, and then collected by filtration. The solid was washed twice with 100 ml of t-butyl methyl ether to give 69.7 g of the title compound.

1. temperatureto warm to −20° C
2. extractionthe mixture was extracted with 4 L of ethyl acetate
3. washThe organic layer was washed successively with 5 L of water and 5 L of a saturated sodium chloride solution
4. dry with materialThe solution was dried over anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. filtrationcollected by filtration
7. washThe solid was washed twice with 100 ml of t-butyl methyl ether