N,N-Diethyl-1,4-butanediamine → 1-Cyclopentyl-7-(4-diethylamino-butylamino)-3-(2,6-difluoro-3,5-dimethoxy-phenyl)-3,4-dihydro-1H-pyrimido[4,5-d]pyrimidin-2-one

Participants

Reaction Steps

In a 1-L round bottom flask, 8.00 g (17.78 mmol) of 1-cyclopentyl-3-(2,6-difluoro-3,5-dimethoxy-phenyl)-7-methylsulfinyl-3,4-dihydro-1H-pyrimido[4,5-d]pyrimidin-2-one in 260 mL of dioxane was treated with 5.10 g (35.36 mmol) of 4-diethylamino-butylamine and heated at reflux for 10 hours under nitrogen atmosphere. The dioxane was evaporated in vacuo. The crude product was purified using medium-pressure chromatography eluting with a gradient of 9:0.5:0.25 to 9:1:0.5 ethyl acetate/methanol/triethylamine to give 8.14 g (86%) of the title compound as a pure partially crystalline solid. A 50 mg portion of the solid was recrystallized with 25% ethanol in hexanes to give 35 mg of title compound as pure crystalline solid: mp 132° C.–133° C. MS (APCI) (m+1)/z 533.3.

Provenance & Evidence