反应详情

A mixture of {9-chloro-1-[6-methoxy-2-(trifluoromethyl)pyridin-3-yl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl}methanol (500 mg, 1.21 mmol), 2,2,6,6-tetramethylpiperidine 1-oxyl (18.9 mg, 0.12 mmol) and sodium nitrate (33.4 mg, 0.484 mmol) in acetic acid (10 mL) was stirred at room temperature and ambient pressure for 64 hr. Water was added to the reaction mixture and the mixture was extracted with ethyl acetate. The organic layer was washed with aqueous sodium hydrogen carbonate and brine, dried over anhydrous magnesium sulfate, and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with a 20-80% ethyl acetate/n-hexane gradient mixture to give the title compound (336.3 mg, 0.82 mmol, 68%) as a pale yellow solid.

1. extractionthe mixture was extracted with ethyl acetate
2. washThe organic layer was washed with aqueous sodium hydrogen carbonate and brine
3. dry with materialdried over anhydrous magnesium sulfate
4. concentrationconcentrated in vacuo
5. customThe residue was purified by flash chromatography on silica gel eluting with a 20-80% ethyl acetate/n-hexane gradient mixture