反应详情

温度

0 °C

To an ice cold solution of [3-chloro-4-(3-dimethylamino-prop-1-ynyl)-phenyl]-carbamic acid tert-butyl ester (4.0 g) in dichloromethane (30 ml) is added in small portions 3-chloroperoxybenzoic acid(2.34 g). After the reaction is stirred at 0° C. for 20 minutes, the mixture is passed over twenty weight equivalents of basic alumina (Brockmann Grade I, 150 mesh) and the N-oxide is eluted using a solution of 5% methanol in dichloromethane. All fractions containing the desired amine N-oxide were combined and evaporated to near dryness under reduced pressure. The residue is treated successively three times with small portions of methanol (ca. 50 ml) followed by evaporation to near dryness under reduced pressure, and the volume of the solution is adjusted to 250 mL by addition of methanol. The methanolic solution of the N-oxide is then heated to reflux for approximately 15 hours, then cooled, and the solvent is evaporated to dryness under reduced pressure. The residue is purified by chromatography over silica gel (80% ethyl acetate in hexanes is used as the eluant) to give the desired product as a pale yellow solid.

1. washthe N-oxide is eluted
2. additionAll fractions containing the desired amine N-oxide
3. customevaporated
4. additionThe residue is treated successively three times with small portions of methanol (ca. 50 ml)
5. customfollowed by evaporation
6. additionthe volume of the solution is adjusted to 250 mL by addition of methanol
7. temperatureThe methanolic solution of the N-oxide is then heated
8. temperatureto reflux for approximately 15 hours
9. temperaturecooled
10. customthe solvent is evaporated to dryness under reduced pressure
11. customThe residue is purified by chromatography over silica gel (80% ethyl acetate in hexanes