反应详情

A mixture of trifluroromethanesulfonic acid (63.2 ml; 0.71 mol) and phosphorus oxychloride (66.4 ml; 0.71 mol) in chlorobenzene (400 ml) was stirred for ½ hour at room temperature. A solution of N-phenyl-3-[2-(3-chlorophenyl)ethyl]-2-pyridine carboxamide 4 (120 g; 0.36 mol) in chlorobenzene (240 ml) was added. The mixture was heated at 110° C. for 18 hours followed by cooling to 50° C. Water (400 ml) was added and the biphasic mixture heated to 80° C. for ½ hour. The mixture was cooled to room temperature, stirred vigorously for 10 minutes, then allowed to stand for 10 minutes. The product was removed by filtration and partitioned between water (300 ml) and toluene (500 ml). The pH of the aqueous phase was adjusted to 10 with 10M NaOH solution. 100 ml of the organic phase was removed by distillation under reduced pressure. Charcoal (5.5 g) was added and the mixture filtered through a pad of celite. The solution was concentrated under vacuum to 300 ml and 150 ml of hexane was added. The mixture was cooled to 0-10° C. for 1 hour with stirring prior to filtration. The product was washed with 100 ml of chilled toluene and then air-dried for several hours. Yield=44.1 g (50.8%)

1. temperatureThe mixture was heated at 110° C. for 18 hours
2. temperatureby cooling to 50° C
3. temperaturethe biphasic mixture heated to 80° C. for ½ hour
4. temperatureThe mixture was cooled to room temperature
5. stirringstirred vigorously for 10 minutes
6. waitto stand for 10 minutes
7. customThe product was removed by filtration
8. custompartitioned between water (300 ml) and toluene (500 ml)
9. custom100 ml of the organic phase was removed by distillation under reduced pressure
10. additionCharcoal (5.5 g) was added
11. filtrationthe mixture filtered through a pad of celite
12. concentrationThe solution was concentrated under vacuum to 300 ml and 150 ml of hexane
13. additionwas added
14. temperatureThe mixture was cooled to 0-10° C. for 1 hour
15. stirringwith stirring
16. filtrationto filtration
17. washThe product was washed with 100 ml of chilled toluene
18. customair-dried for several hours