Hexachloroethane → 5-Benzyloxymethyl-2-chloro-4-oxo4,5-dihydroimidazo[4,5-d]pyridazine-1-sulfonic acid dimethylamide

Temperature

-78 °C

5.3 ml of n-butyl lithium (2.0 M cyclohexane solution) was added to a 150-ml tetrahydrofuran solution of 3.34 g of 5-benzyloxymethyl-4-oxo-4,5-dihydroimidazo[4,5-d]pyridazine-1-sulfonic acid dimethylamide under a nitrogen atmosphere at −78° C., and the mixture was stirred at −78° C. for one hour. Then, 20 ml of a tetrahydrofuran solution of 3.26 g of hexachloroethane was added to this solution. The mixture was allowed to warm to room temperature. 25 ml of a 5% aqueous solution of ammonium chloride was added to the solution, and the mixture was extracted with 50 ml of ethyl acetate. The organic layer was washed successively with 25 ml of water and 25 ml of a saturated sodium chloride solution, and then dried over anhydrous magnesium sulfate. The organic liquid was concentrated under reduced pressure. The residue was purified by silica gel column chromatography. Thus, 2.31 g of the title compound was obtained from the fraction eluted with hexane-ethyl acetate (2:3).

1. temperatureto warm to room temperature
2. extractionthe mixture was extracted with 50 ml of ethyl acetate
3. washThe organic layer was washed successively with 25 ml of water and 25 ml of a saturated sodium chloride solution
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationThe organic liquid was concentrated under reduced pressure
6. customThe residue was purified by silica gel column chromatography

ORD record

ord-89d218b817024225a9ad80ef8521974f

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07772226B2