反应详情

Into the same reactor as in example 1, were poured, under nitrogen circulation, 300 ml of toluene, 12.2 g (0.025 mol) of the product of example 1 and 4.75 g (0.0117 mol) of Lawesson's reagent. The reaction mixture was slowly warmed over two hours to reflux temperature and reflux was maintained for two hours. After evaporation to dryness and treatment with dichloromethane, the solution was passed on a silica gel column, eluting with dichloromethane:methanol 95:5 by volume. After evaporation to dryness of the resulting solution, the residue was recrystallized from methanol. Yield 10.2 g (82%).

1. temperatureThe reaction mixture was slowly warmed over two hours
2. temperatureto reflux temperature
3. temperaturereflux
4. temperaturewas maintained for two hours
5. customAfter evaporation to dryness and treatment with dichloromethane
6. washeluting with dichloromethane:methanol 95:5 by volume
7. customAfter evaporation to dryness of the resulting solution
8. customthe residue was recrystallized from methanol