反应详情

A solution of 5-chloro-2-nitro-toluene (895 mg, 5.23 mmol) in diglyme (2.5 mL) was added to a stirred suspension of 1-(4,6-dimethyl-pyridin-2-yl)-piperazine (500 mg, 2.62 mmol) and potassium carbonate (900 mg, 6.54 mmol) in diglyme (5 mL) and heated at reflux overnight. The mixture was cooled, the inorganic salts filtered off and washed with ethyl acetate. The filtrate was concentrated to dryness under high vacuum to obtain a residue which was dissolved in 6N hydrochloric acid (10 mL) and washed with toluene. The aqueous layer was basified to pH 8 with ammonium hydroxide solution and extracted with ethyl acetate. The organic layer was washed with water, bicarbonate solution, and brine dried over sodium sulfate, filtered and concentrated to dryness to give the crude compound. Purification by column chromatography over silica gel (60-120 mesh) using 15% ethyl acetate in hexane as a eluent afforded 1-(4,6-dimethyl-pyridin-2-yl)-4-(3-methyl-4-nitro-phenyl)-piperazine (380 mg, 45%).

1. temperatureheated
2. temperatureat reflux overnight
3. temperatureThe mixture was cooled
4. filtrationthe inorganic salts filtered off
5. washwashed with ethyl acetate
6. concentrationThe filtrate was concentrated to dryness under high vacuum
7. customto obtain a residue which
8. washwashed with toluene
9. extractionextracted with ethyl acetate
10. washThe organic layer was washed with water, bicarbonate solution, and brine
11. dry with materialdried over sodium sulfate
12. filtrationfiltered
13. concentrationconcentrated to dryness
14. customto give the crude compound
15. customPurification by column chromatography over silica gel (60-120 mesh)