反应详情

温度

115 °C

682 mg of 2-cyano-3,5-difluoropyridine, 995 mg of 4-amino-1,2,2,6,6-pentamethylpiperidine and 1.346 mg of potassium carbonate in 10 ml of dimethyl sulphoxide are introduced into a 20 ml microwave tube reactor. The mixture is then heated in the microwave for 1 hour at 115° C. The reaction medium is run into 100 ml of water and 100 ml of ethyl acetate. The aqueous phase is re-extracted twice with 50 ml of ethyl acetate. The combined organic phases are washed with water and then with a saturated aqueous solution of sodium chloride, dried over sodium sulphate and concentrated under reduced pressure. After purification by flash chromatography on 70 g of silica gel, elution being carried out with a mixture of dichloromethane, methanol and 4N aqueous ammonia (99/1/0.8 by volume), and the first eluted product being recovered, 290 mg of 2-cyano-5-fluoro-3-(1,2,2,6,6-pentamethylpiperidin-4-yl)aminopyridine are thus obtained in the form of an ecru powder, the characteristics of which are the following:

1. extractionThe aqueous phase is re-extracted twice with 50 ml of ethyl acetate
2. washThe combined organic phases are washed with water
3. dry with materialwith a saturated aqueous solution of sodium chloride, dried over sodium sulphate
4. concentrationconcentrated under reduced pressure
5. customAfter purification by flash chromatography
6. washon 70 g of silica gel, elution
7. additionbeing carried out with a mixture of dichloromethane, methanol and 4N aqueous ammonia (99/1/0.8 by volume)
8. customthe first eluted product being recovered