Sodium hydride → 1-Cyclopentyl-3-(2,6-difluoro-3,5-dimethoxy-phenyl)-7-methylsulfanyl-4H-pyrimido[4,5-D]pyrimidin-2-one

Participants

Reaction Conditions

Reaction Steps

A solution of 16.33 g (0.0398 mol) of cyclopentyl-(5-[(2,6-difluoro-3,5-dimethoxy-phenylamino)-methyl]-2-methylsulfanyl-pyrimidin-4-yl)-amine in 288 mL of anhydrous tetrahydrofuran was cooled to 0° C. using an ice/acetone bath. The reaction mixture was treated with 3.98 g (0.0995 mol) of sodium hydride and continued stirring at 0° C. for 30 minutes. After 30 minutes, 19.35 g (0.019 mol) 1,1′-carbonyldiimidazole was added and continued to stir at 0° C. for an additional 30 minutes. After 1 hour, the ice bath was removed and the reaction mixture was allowed to warm up to room temperature. The reaction mixture heated at reflux overnight under nitrogen atmosphere. Evaporated the tetrahydrofuran and partitioned the residue between dichloromethane and water. The aqueous layer was extracted one time with 500 mL dichloromethane. The dichloromethane extracts were combined, dried over sodium sulfate, filtered and evaporated. There was a portion of the crude material that did not dissolve in the eluent. Filtered the solid and dried in the housevac oven overnight to give the title compound, 6.80 g of crop 1. The remaining crude material was purified using medium pressure-chromatography, eluting with a gradient of 2:1 hexanes/ethyl acetate to 1:1 hexanes/ethyl acetate to give the title compound as a white solid, 8.74 g of crop 2. Combined the crops to give a total of 15.54 g (90%) of the title compound. MS (APCI) (m+1)/z 437.1.

Provenance & Evidence