Potassium Carbonate → 5-[9-Chloro-6-(1-ethylpropyl)-3,4-dihydropyrimido[1,2-a]benzimidazol-1(2H)-yl]-N,N,4-trimethylpyridin-2-amine

Participants

Reaction Steps

To a solution of 3-[4-chloro-2-{[6-(dimethylamino)-4-methylpyridin-3-yl]amino}-7-(1-ethylpropyl)-1H-benzimidazol-1-yl]propan-1-ol (100 mg, 0.233 mmol) in pyridine (2 mL) was added methanesulfonyl chloride (0.036 mL, 0.465 mmol) dropwise at 0° C. After stirring for 2 hr at room temperature, aqueous sodium bicarbonate was added and the mixture was extracted with ethyl acetate. Organic layer was washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo. The crude mesylate was dissolved in 1-methyl-2-pyrrolidinone (1.0 mL) and potassium carbonate (64 mg, 0.465 mmol) was added. The mixture was stirred at 50° C. for 4 hr. Water was added and the mixture was extracted with ethyl acetate. Organic layer was washed with water and brine, dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with a 50-80% ethyl acetate/n-hexane gradient mixture followed by recrystallization from ethyl acetate/n-hexane to afford the title compound (50 mg, 0.12 mmol, 52%) as a colorless solid.

Provenance & Evidence