反应详情

To a solution (15 mL) of ethyl 3-{[(4-{[(5-bromo-3-methyl-1-benzofuran-2-yl)(cyclohexyl)methyl]amino}phenyl)carbonyl](methyl)amino}-propanoate (0.54 g) synthesized in Example A174(3) in toluene were added (3,5-dimethylisoxazol-4-yl)boronic acid (0.41 g) and 2N aqueous sodium carbonate solution (1.46 mL), and the mixture was stirred at room temperature for 10 min under argon atmosphere. To the reaction mixture were added 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (0.05 g) and tris(dibenzylideneacetone)dipalladium (0) (0.03 g), and the mixture was heated under reflux under argon atmosphere overnight. The reaction mixture was cooled to room temperature and filtered through celite, and the residue was washed with diethyl ether. Water was added to the filtrate, and the organic layer was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:1, volume ratio) to give ethyl 3-[{[4-({cyclohexyl[5-(3,5-dimethylisoxazol-4-yl)-3-methyl-1-benzofuran-2-yl]methyl}amino)phenyl]carbonyl}(methyl)amino]propanoate (0.13 g, 23%) as a pale-yellow oil. The obtained oil was dissolved in ethanol (1 mL), 1N aqueous sodium hydroxide solution (1.0 mL) was added to the solution at room temperature, and the mixture was stirred at room temperature for 0.5 hr. Ethanol was evaporated under reduced pressure, and 1N hydrochloric acid (1.0 mL) was added to the residue. The precipitate was washed with water to give the title object compound (0.12 g, 96%) as a colorless solid.

1. temperaturethe mixture was heated
2. temperatureunder reflux under argon atmosphere overnight
3. temperatureThe reaction mixture was cooled to room temperature
4. filtrationfiltered through celite
5. washthe residue was washed with diethyl ether
6. additionWater was added to the filtrate
7. concentrationthe organic layer was concentrated under reduced pressure
8. customThe residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:1, volume ratio)