反应详情

1-Acetyl-4-(4-amino-3-methylphenyl)piperazine (7.89 g) was dissolved in pyridine (130 ml). Methanesulphonyl chloride (7.9 ml) was added dropwise with stirring. The mixture was reduced in volume after 2 hours by evaporation and then stirred overnight. The resulting slurry was partitioned between water (125 ml) and dichloromethane (100 ml), and the aqueous layer was further extracted with dichloromethane (2×100 ml), 5% methanol in dichloromethane (2×100 ml), and ethyl acetate (2×125 ml). The combined organic layers were dried (sodium sulphate) and evaporated, and the residue was chromatographed in 5% methanol in dichloromethane over t.l.c. grade silica, the product-containing fractions, after evaporation, yielding a foam (5.93 g), Rf 0.29 (5% methanol/dichloromethane/silica), used directly in step (D). A small sample from a second run was recrystallized from ethyl acetate/hexane, m.p. 153°-4°.

1. customThe mixture was reduced in volume after 2 hours by evaporation
2. stirringstirred overnight
3. customThe resulting slurry was partitioned between water (125 ml) and dichloromethane (100 ml)
4. extractionthe aqueous layer was further extracted with dichloromethane (2×100 ml), 5% methanol in dichloromethane (2×100 ml), and ethyl acetate (2×125 ml)
5. dry with materialThe combined organic layers were dried (sodium sulphate)
6. customevaporated
7. customthe residue was chromatographed in 5% methanol in dichloromethane over t.l.c
8. customgrade silica, the product-containing fractions, after evaporation