反应详情

A mixture of ethyl 4-[2,4-dichloro-7-(1-ethylpropyl)-1H-benzimidazol-1-yl]butanoate (Reference Example 33; 1.50 g, 4.04 mmol), 6-methoxy-4-methylpyridin-3-amine (1.10 g, 8.09 mmol) and p-toluenesulfonic acid monohydrate (487 mg, 2.83 mmol) in 1-methyl-2-pyrrolidinone (8 mL) was irradiated by microwave at 180° C. for 10 min. After cooling, the mixture was diluted with ethyl acetate, washed with aqueous sodium bicarbonate, water and brine, dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was purified by flash chromatography on silica gel eluting with a 20-50% ethyl acetate/n-hexane gradient mixture. The filtrate was concentrated in vacuo to give an amorphous which was recrystallized from ethyl acetate/n-hexane to give the title compound (190 mg, 0.402 mmol, 10%) as a colorless solid.

1. customwas irradiated by microwave at 180° C. for 10 min
2. temperatureAfter cooling
3. washwashed with aqueous sodium bicarbonate, water and brine
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated in vacuo
6. customThe residue was purified by flash chromatography on silica gel eluting with a 20-50% ethyl acetate/n-hexane gradient mixture
7. concentrationThe filtrate was concentrated in vacuo
8. customto give an amorphous which
9. customwas recrystallized from ethyl acetate/n-hexane