反应详情

温度

-20 °C

Gradually, 3-chloroperoxybenzoic acid (10.76 g) was added to a solution of 2-chloro-4-(3-dimethylamino-propyn-1yl)-benzoic acid, methyl ester (15.07 g in dichloromethane (40 ml), at a rate to maintain the reaction temperature at −20° C. The mixture was stirred for 10-15 minutes. The resulting N-oxide was purified by chromatography on Activity Grade I basic alumina (215 g), eluting with 10% methanol/dichloromethane. The solvent was evaporated in vacuo between 12 to 18° C. The resulting residue was dissolved in methanol (100 ml) and heated at 60-65° C. with stirring for 18 hours. After removing the solvent in vacuo, and the product was purified by column chromatography on silica gel (190 g), eluting with 70% ethyl acetate/hexane. Trituration with diethyl ether containing some hexane afforded the title compound as a solid (5.68 g), m.p. 92-96° C.

1. customThe resulting N-oxide was purified by chromatography on Activity Grade I basic alumina (215 g)
2. washeluting with 10% methanol/dichloromethane
3. customThe solvent was evaporated in vacuo between 12 to 18° C
4. dissolutionThe resulting residue was dissolved in methanol (100 ml)
5. temperatureheated at 60-65° C.
6. stirringwith stirring for 18 hours
7. customAfter removing the solvent in vacuo
8. customthe product was purified by column chromatography on silica gel (190 g)
9. washeluting with 70% ethyl acetate/hexane