反应详情

A mixture of 2-benzyloxy-1-chloro-4-nitro-benzene (700 mg, 2.66 mmol), 1-(4,6-dimethyl-pyridin-2-yl)-piperazine (457 mg, 2.39 mmol) and caesium carbonate (2.58 g, 7.97 mmol) in toluene (30 mL) was purged with argon gas. Palladium acetate (24 mg, 0.106 mmol) and 2-(dicyclohexylphosphino)-2′-N,N-dimethylamino)-biphenyl (42 mg, 0.106 mmol) were added. After purging again with argon gas the reaction mixture was heated at reflux for 20 h. The reaction mixture was cooled, filtered and the filter cake was washed with ethyl acetate (30 mL). The combined filtrate and washings were washed successively with water (2×50 mL), brine (2×50 mL), dried over anhydrous sodium sulfate and concentrated in vacuo to yield a residue which was purified by flash column chromatography over silica gel (100-200 mesh) using 8-10% ethyl acetate in petroleum ether as eluent to afford 1-(2-benzyloxy-4-nitro-phenyl)-4-(4,6-dimethyl-2-pyridyl)piperazine (510 mg, 46%) as a pale yellow solid.

1. customwas purged with argon gas
2. customAfter purging again with argon gas the reaction mixture
3. temperaturewas heated
4. temperatureat reflux for 20 h
5. temperatureThe reaction mixture was cooled
6. filtrationfiltered
7. washthe filter cake was washed with ethyl acetate (30 mL)
8. washThe combined filtrate and washings were washed successively with water (2×50 mL), brine (2×50 mL)
9. dry with materialdried over anhydrous sodium sulfate
10. concentrationconcentrated in vacuo
11. customto yield a residue which
12. customwas purified by flash column chromatography over silica gel (100-200 mesh)